Saturday, July 31, 2010
Friday, July 30, 2010
Numbers, Words and Colors | MIT World
About the Lecture
Tools developed by Martin Wattenberg and his associate Fernanda Viégas, have changed the way people look at and use visualizations, by empowering and equipping users with the methodology needed to ask different questions. Wattenberg, whose background is in math and computer science, asks how the humanities have influenced the evolution of data visualization and then answers with several examples from his own work.Web Seer compares Google's "auto-suggest" feature in one-to-one, weighted comparisons such as "why doesn't he…" and "why doesn't she…" The resultant text image uses the size of arrows and words to reflect frequency, demonstrating how text can impart meaning.
Another Wattenberg/Viégas collaboration is Many Eyes, a social media tool and Web site that has "democratized" powerful visualization systems by putting them in the hands of general audiences. This tool lets users visualize data in numerous ways, from scatterplots and bar charts to tree maps and stack graphs.
Word Tree, a visualization technique that lets users pick a word or phrase from a data set, shows the different contexts in which it appears via a tree-like branching structure. Chimera takes care of the "boilerplate problem" by examining large collections of text, such as contracts, and pointing out identical phrases. Seeing results arranged in faux 3D "skyscrapers" clearly illustrates levels of recurrence. Although Word Tree andChimera are fundamentally repetition searches, they are important tools for semantic analysis: simple, but revealing.
The idea behind Phrase Net is to expose a text's underlying network; this visualization tool diagrams the relationships between different words used in a text. It uses a simple form of pattern matching to provide multiple views of the concepts contained a book, speech, or poem.
Another Wattenberg/ Viégas collaboration is Fleshmap, "an inquiry into human desire." The relationship between the body and its visual and verbal representation are explored in a series of artistic studies employing song lyrics and body imagery. Flickr Flow, Wattenberg explains, is an experiment whose materials are color and time. Software calculated the relative proportions of different colors seen in photos of Boston taken during each month of the year and plotted those colors on a wheel creating a "river of meaning."
Wattenberg addresses questions regarding the impact of race in personified visualizations, and his subjective motives in selecting particular data for analysis. He admits that his "hard drive is loaded with failed visualizations," but emphasizes that the visualization process should be one of trial and error. As for encouraging the development of visual literacy, Wattenberg concludes, "as visualization becomes part of the discourse and people realize, 'this is something that's powerful, it can help me make my case in life,' they'll learn… I'm hoping for education and good, old-fashioned human brain power."
Numbers, Words and Colors | MIT World
Tuesday, July 27, 2010
Thursday, July 22, 2010
Caroline Myss interviews the Red Hot Chilli Peppers
Caroline Myss interviews the Red Hot Chilli Peppers
The Red Hot Chilli Peppers discuss the shift in their awareness.
Wednesday, July 21, 2010
Tuesday, July 20, 2010
The Extended Mind: Recent Experimental Evidence
Google Tech Talks
September 2, 2008
ABSTRACT
We have been brought up to believe that the mind is located inside the head. But there are good reasons for thinking that this view is too limited. Recent experimental results show that people can influence others at a distance just by looking at them, even if they look from behind and if all sensory clues are eliminated. And people's intentions can be detected by animals from miles away. The commonest kind of non-local interaction mental influence occurs in connection with telephone calls, where most people have had the experience of thinking of someone shortly before they ring. Controlled, randomized tests on telephone telepathy have given highly significant positive results. Research techniques have now been automated and experiments on telepathy are now being conducted through the internet and cell phones, enabling widespread participation.
Speaker: Rupert Sheldrake
Rupert Sheldrake, Ph.D. is a biologist and author of more than 75 technical papers and ten books, the most recent being The Sense of Being Stared At. He studied at Cambridge and Harvard Universities, was a Fellow of Clare College, Cambridge and a Research Fellow of the Royal Society. He is currently Director of the Perrott-Warrick project, funded from Trinity College Cambridge.
Category:
Articles and Papers - Scientific Papers - Ageing of Cells - Ageing, Growth and Death of Cells
From Articles and Papers - Scientific Papers - Ageing of Cells - Ageing, Growth and Death of Cells
http://www.sheldrake.org/Articles&Papers/papers/ageing/AgeingofCells.html
The Ageing, Growth and Death of Cells
Nature, Vol. 250, No. 5465, pp. 381-385, August 2, 1974
by Rupert Sheldrake
No cell is immortal. If a cell grows and divides, it becomes two cells; if it does not divide, sooner or later it dies. Multicellular organisms are not aggregates of cells in a state of exponential growth and division. Some cells divide, but most differentiate and do not undergo further division. Here I shall discuss the ageing and death of cells in vascular plants and vertebrate animals in an attempt to explore the significance of these processes in relation to growth and development, both normal and abnormal.
It is often convenient to think of cells of living organisms as maintaining a more or less steady state; but it is also easy to forget that this is an approximation, an abstraction which, if realised, would confer on cells and on organisms the doubtful blessings of eternal life and eternal youth. The realities of growth, development, ageing and death cannot be understood in terms of steady state concepts. They are directional and irreversible changes in time.
Some cells die as they differentiate, for example xylem cells in plants and keratinised epidermal cells in animals; some, such as phloem sieve tubes in plants and red blood cells in mammals, lose their nuclei; others which retain their nuclei may lose their ability to divide - as do most nerve cells. But even cells which retain their ability to divide will die if they do not do so; they senesce.
Any general hypothesis of cellular ageing must not only explain cellular ageing itself, but also the way in which some cell lines do not senesce and die out. The germ cell line is continuous from generation to generation (also many plants can be propogated vegetatively indefinitely) and some cell lines derived from plant or animal tissues can be propagated in vitro for an indefinite number of generations.
General hypotheses of ageing based on genetic mutation face two difficulties. First, in explaining the universality of the processes of ageing in non dividing cells in terms of a lethal accumulation of harmful mutations and, second, in accounting for the facts of sexual and vegetative reproduction, which show that mutations do not accumulate to a lethal extent in all cells. The alternative to a genetic-mutation hypothesis of ageing is some sort of 'cytoplasmic' hypothesis, the most recent and best known of which is Orgel's 'error catastrophe' hypothesis, which postulates that an accumulation of errors in protein synthesis leads to a positive feedback of error as the enzymes involved in protein synthesis themselves develop errors and thus produce more defective proteins1. For this hypothesis to account for the continuity of the germ line and the indefinite propagation of 'permanent cell lines' in vitro it is necessary to postulate a process of 'cellular selection' whereby error-containing cells are selected out.
Neither the genetic-mutation hypothesis nor the protein synthesis 'error catastrophe' hypothesis of ageing are supported by sufficient evidence to rule out the possibility that cellular ageing may be explicable in terms of the accumulation of cytoplasmic breakdown products, some of which might be deleterious to the cell if they accumulated sufficiently. In all actively metabolising cells, there is a turn-over of cytoplasmic constituents such as proteins and membrane lipids. More is known about their synthesis than about their breakdown in vivo; while some of them may be broken down completely, others may be broken down only partially or not at all. They must therefore accumulate.
Lipid peroxidation
One example of such an accumulation is provided by the 'age pigment' or lipofuscin granules which accumulate in an age-dependent way in the cells of many mammalian tissues4. The lipofuscin material contains lipid and protein and may be formed in autophagosomal vesicles, for example during the digestion of mitochondria; haem groups, released as the cytochromes are degraded, may catalyse the peroxidation of unsaturated lipids in the degenerating mitochondrial membranes which may cross link with each other and with denatured proteins 6. The cells seem to be unable to destroy these cross-linked polymers. Lipofuscin granules do not seem to damage cells directly except when they accumulate, as they do in certain diseases, to such an extent that they mechanically interfere with the structure and functions of the cell.
Lipid peroxidation does not always result in the formation of microscopically visible lipofuscin granules, nor is it confined to autophagosomal vesicles; it occurs in all functional cell membranes, including the surface membrane. Once the peroxidation of unsaturated lipids is initiated, by haem groups, Fe2+ ions and other simple catalysts in the presence of oxygen, it takes place by a free radical chain reaction. It can be inhibited by lipid-soluble antioxidants such as vitamin E and accelerated by vitamin E deficiency, ionising radiation, chloroform and ethanol poisoning and hyperbaric treatments 8,9, which can cause irreversible damage to cells.
The peroxidation of lipids within cell membranes is occurring in vivo all the time. Some peroxidised lipids may be metabolised but others, perhaps those which are cross linked to other lipids and lipoproteins may not be. The chain reaction of lipid peroxidation may be terminated by the oxidation of other substances which may themselves be damaged and accumulate. Such substances formed within the surface membrane, for example, may accumulate in situ; if they are removed from the surface membrane as the membrane is recycled by the invagination of membrane vesicles11-14 or by other means, some of them might find their way into residual bodies, but they might also be incorporated into intracellular membranes. The formation and accumulation of such substances within the outer and intracellular membranes, for example in the Golgi apparatus, endoplasmic reticulum nuclear membrane and lysosomal membranes, could well be deleterious to normal membrane functioning and could also lead to a positive feedback of damage by further lipid peroxidation, and thus to the senescence and death of the cell. The rate of ageing would be temperature dependent and would also depend on the composition, structure and functions of the cellular membranes, the extra - and intracellular environments, antioxidant levels and so on. Thus, different types of cells would age at different rates but, according to this hypothesis, all cells would be ageing to a greater or lesser extent all the time; all cells would be heading towards senescence and death.
The elimination of membranous material from cells might enable the ageing process to be retarded and there are a few examples of the shedding of membranes by cells which I will discuss further. But, in general, the only way in which cells could avoid their otherwise inevitable mortality would be by growing and dividing, thus diluting the accumulated breakdown products. Although lipid peroxidation may be the most important cause of the formation of such substances, the following general considerations could apply to any deleterious substances which accumulate with age.
Growth and division of cells
An artificially simple case is provided by cells dividing symmetrically with a fixed generation time if these accumulate deleterious breakdown products linearly with time, an amount, x, being formed per cell generation time. Successive generations contain more of the accumulated breakdown products but the increments become smaller and smaller. If the rate of accumulation is not linear, but proportional to the amount already accumulated, the content per cell will increase exponentially; and if there is a progressive lengthening of the cell generation time, there will be a greater accumulation within individual cells in succeeding generations. With either or both of these assumptions, it can be seen that the whole population will undergo senescence and sooner or later die out.
But another type of cell division is possible, an asymmetrical division in which one of the daughter cells receives all or most of the accumulated breakdown products (becoming more 'mortal') while the other is rejuvenated, receiving little or none. The more 'mortal' of the daughter cells might die or differentiate directly, or it might divide again unequally, producing a rejuvenated cell and a cell even more 'mortal' than itself, or it might undergo one or more sequential symmetrical divisions (as discussed above) to produce a population of cells which sooner or later die (unless they can undergo further asymmetrical divisions to produce rejuvenated cells).
I shall now consider a few aspects of the growth and development of higher plants and higher animals in the light of these ideas. Dicotyledonous trees illustrate the pattern of indefinite growth that is characteristic of plants. (There are of course plants, such as herbaceous annuals, which die after they have flowered. But annuals are capable of growing for much longer than their normal life-span if they are prevented from flowering, indicating that they die because they flower and not because of an innate inability to go on growing15.) The life span of trees is limited by a variety of mechanical factors, but cuttings taken from old trees can give rise to healthy young trees, and this process can be repeated indefinitely. The growing points of the tree, the apical meristems, remain perpetually young.
Cell divisions within the apical meristems of the shoots give rise to daughter cells with different fates: some remain meristematic, others give rise to the differentiated structures of the stems and the leaves. Some of these cells die as they differentiate into vascular tissues and fibres, others, for example the leaf mesophyll and pith parenchyma, remain alive for some time, but, unless they are stimulated to divide again in a regenerative response to wounding or damage, they eventually die. The leaves senesce and fall from the tree; the pith breaks down. The root meristems give rise to the primary tissues of the root which, apart from those which divide to produce further root meristems, sooner or later die. In secondarily thickening stems the divisions of the cambial cells give rise to cells which die as they differentiate into xylem or undergo further asymmetrical divisions to produce phloem companion cells and sieve tubes. These cells eventually die and are sloughed off in the bark. Cell divisions in the cork cambium give rise to cork cells which die as they differentiate; divisions of the root cap initials give rise to root cap cells which die and are sloughed off. Thus, in the various meristems of the plant the continued growth and continued rejuvenation of the meristems is associated with the production of cells which die during or after differentiation.
Vertebrates
Vertebrates, unlike trees, do not go on growing indefinitely, nor can they be propagated vegetatively. At first, fertilised eggs undergo cleavages which rapidly increase the number of cells, but this rate of increase of cell number declines progressively as the animal develops, and as cells and tissues differentiate16. Throughout the development of the embryo many tissues and groups of cells regress and die17,18. Some of these cell deaths are associated with tissue differentiation19, some occur during morphogenetic processes20, and others may represent the regression of phylogenetically vestigial structures17, but the significance of other cell deaths is obscure. As the animal develops, the cells of some tissues, such as nerve and muscle, differentiate and to a large extent lose the ability to undergo further division. Some of these cells die as the animal grows older and are not replaced21,22 but in the adult animal a number of other tissues continue to grow, for example the epidermis, the intestinal lining, the liver and blood cells continue to be formed. In all these examples the production of new cells is offset by cell death. Cell divisions in the basal layers of the mammalian epidermis give rise to daughter cells which remain in the basal layers and divide again, and other daughter cells which differentiate and keratinise, dying as they do so. Cell divisions in the crypts of the intestinal villi replenish the population of crypt cells capable of further division and produce other daughter cells which move up the villi where they die and are sloughed off23. Asymmetrical divisions of the early precursors of all cells of the blood occur throughout life and give rise to further precursor cells as well as to the maturing and mature cells of the blood, all of which have a limited life span. During the formation of red blood cells24 and granulocytes25 in the bone marrow, and lymphocytes in the thymus26, considerable numbers of cells die in situ soon after they are formed. The reasons for this 'ineffective' erythropoiesis, granulopoiesis and lymphopoiesis are unknown.
The mortality of at least some of the cells which die in developing animal embryos and in mature animals may represent the price that is paid for the rejuvenation of other cells which continue to grow and divide. But unfortunately too little is known about cell lineages in animals, especially in embryos, for it to be possible to decide how general is the phenomenon of asymmetrical cell divisions giving rise to daughter cells of unequal mortality. The recognition of this pattern is complicated by the fact that by no means all cell death takes place as a result of cellular senescence. Some cells die as they differentiate and others may die because they find themselves in the wrong places at the wrong times19. Cell deaths may be controlled chemically, for example by steroid hormones: the injection of glucocorticoids can cause large numbers of lymphocytes to die27, the regression of Mullerian and Wolffian ducts is controlled by androgens and oestrogens19,28 and the regression of the lining of the female genital tract is under the control of oestrogens28. But, under the hypothesis that asymmetrical cell divisions lead to a rejuvenation of 'meristematic' daughter cells at the price of the increased mortality of their sister cells, it does not matter whether the latter die as a result of senescence, or whether they die as they differentiate or for any other reason.
Sexual reproduction
In the sexual reproduction of both higher plants and higher animals almost all the cytoplasm from which the embryo and the new organism develops is provided by the egg. In both cases, the egg cells are formed as a result of asymmetrical divisions of the egg mother cell. In the great majority of higher plants, the meiotic divisions of the egg mother cell produce four cells, three of which die. The fourth undergoes further divisions to produce the cells of the embryo sac, most of which die before or shortly after fertilisation. In some species, one of more of the three sister cells of the cell which gives rise to the egg may undergo further division to produce short-lived embryo sac cells29. In animals the first and second meiotic divisions of the egg mother cell give rise to the first and second polar bodies, which regress and die.
It is particularly striking that in both plants and animals, only one of the progeny of the egg mother cell gives rise to an egg while the sister cells die (or if they divide give rise to short-lived progeny). By contrast, there is no comparable cell loss in male gametogenesis associated with the meiotic divisions of the pollen mother cells and spermatogonia.
The many examples in both higher plants and higher animals (and many more can be found in the lower plants and lower animals) of the production of rejuvenated meristematic, stem or egg cells by asymmetrical divisions do not of course prove that these divisions involve an asymmetrical distribution of deleterious breakdown products; but the available facts appear to be consistent with this hypothesis.
Loss of membranous material by animal cells
If the accumulation of deleterious breakdown products of membrane lipids is one of the causes of cellular senescence, the loss of membranous material might be of considerable importance in enabling cells to rid themselves of such substances. The shedding of membranous material by living cells does not seem to be of common occurrence but can take place in mammalian cells as follows.
First, in apocrine secretions part of the cell membrane is lost. The best example, and the only one for which conclusive ultrastructural evidence exists, is in the secretion of lipid droplets by the cells of lactating mammary glands. The secreted lipid droplets are surrounded by a unit membrane derived in part from the surface membrane and in part from Golgi vesicle membranes.
Second, membrane-bounded vesicles of cytoplasm can break away from mammalian macrophages both in vitro and in vivo. This process, known as clasmotosis, is of unknown significance. Lymphocytes which are activated in immunological reactions or as a result of phytohaemagglutinin stimulation form 'tails' (uropods) which can bleb off vesiculated buds in vivo and in vitro. Again, the significance of this process is unknown. Clasmotosis is also frequently observed in cultures of fibroblasts.
Third, many types of animal viruses are budded off from host cells in membrane-bounded vesicles. The protein in the membrane of the vesicles is largely viral, at least in the case of RNA tumour viruses, but the lipids are derived from the host cell membrane35. Viral particles bounded by membrane are also budded off from the cells of a number of spontaneously cancerous tissues and from many of the cell strains and permanent cells lines which are commonly cultured in laboratories.
Tissue cultures
Many plants callus cultures can be grown indefinitely in vitro. During the early stages of the growth of some calluses, an exponential increase in cell number takes place at a rate which suggests that many of the cells may undergo a limited number of sequential symmetrical divisions before the growth rate declines but in most plant tissue cultures the rate of increase of cell number is more or less linear for most of the growth period39,40. Linear growth characteristics would be compatible with a meristematic pattern of cell division such that some daughter cells continue to grow and divide while their sister cells age and sooner or later die. Unfortunately nothing is known in detail about cell lineages within these cultures, nor are there any quantitative data on cell death. Nevertheless, dead and dying cells are by no means uncommon.
'Permanent' mammalian cell lines capable of indefinite propagation in vitro can be derived from cancerous tissues and also from cells which have undergone a spontaneous 'transformation' during culture. Diploid fibroblast cultures can be propagated, however, only for a finite number of subculturings, more (up to about 60) if the cells are derived from embryonic tissues, fewer if they are derived from mature organisms41. The number of generations through which the cells can be passed before the population senesces and dies out is reduced if the period of time between the subculturings is increased42. Fibroblasts of the mouse L strain have been observed to divide symmetrically over six to seven cell generations with a more or less constant generation time43; if the cells in the diploid fibroblast cultures also divide symmetrically, deleterious breakdown products might accumulate in the cells of succeeding generations, as discussed above, and account for the senescence of these cultures. It is impossible, however, to make any detailed interpretation of the senescence of these cultures in the absence of quantitative information about the proportions of dividing and nondividing cells, the incidence of cell death, and the extent and significance of clasmotosis within these cultures - or indeed with cultures of 'transformed' and 'permanent' cell lines.
Cancer
Malignancy must not only involve the freeing of cells from the normal controls on their proliferation, but also the avoidance of senescence by at least a part of the cell population. Many animal tumours contain a stem cell or 'meristematic' population which gives rise to daughter cells which may or may not differentiate, but which sooner or later die. There are numberous examples of cell death within cancerous tissues45-48. Some of the cell deaths can be explained in terms of an inadequate vascularisation of the tumour tissue, but in most tumours this is by no means the only cause an does not apply to all to leukaemias; many of the cells may die as a result of ageing.
Little attention has been paid to the incidence of cell death within cultures of cancerous cells and it is therefore at present impossible to know to what extent the patterns of cell division, ageing and death within these cultures resemble those within in vivo cancers. It is sometimes assumed, if only implicitly, that overall exponential growth characteristics of cell cultures mean that there is a homogeneous population of symmetrically dividing cells. This assumption is not justified: a heterogeneous population containing proliferating, nonproliferating and dying cells can also grow exponentially if the proportion of cells that die is constant with time.
It is conceivable that the loss of membranous material either spontaneously, as in certain types of mammary gland tumours, or as a result of the budding off of viruses (such as RNA tumour viruses) could play a significant role in the retardation of cellular senescence in certain types of cancer.
Effects of cell death
Very little is known about the biochemistry of dying cells. Such cells probably release all sorts of proteins, glycoproteins, peptides, amino acids, amino acid breakdown products, nucleic acids and nucleic acid breakdown products, lipids and lipid breakdown products as well as salts and other substances which were sequestered inside the cells.
It has recently been found that in higher plants the hormone auxin (indole-3-acetic acid) is formed as a consequence of cell death as tryptophan, released by proteolysis, is broken down. Dying cells in differentiating vascular tissue, regressing nutritive tissues and so on, are probably the major source of this hormone within the plant52. Other plant hormones may also be produced by damaged and dying cells: ethylene from the breakdown of methionine and cytokinins by the hydrolysis of transfer RNA. In higher plants the normal production of hormones as a consequence of cell death and the production of 'wound hormones' by damaged cells can be seen as two aspects of the same phenomenon.52
Wound and regenerative responses in vertebrates cannot be explained simply in terms of wound hormones, but there is evidence that dying cells release substances that stimulate phagocytosis53, and affect growth and development in both normal54,55 and cancerous tissues56. And at least some of the cell deaths which occur during normal embryonic development may well result in the production or release of substances involved in the control of differentiation and development.
Dying cells may not only have a chemical effect on neighbouring cells but also a physical effect as cell to cell contacts are broken. Cell deaths within a tissue may also affect the functioning of the tissue as a whole: for example, the death of nerve cells within the brain22 seems likely to affect pathways or patterns of nervous conduction, perhaps leading to the formation of new pathways or patterns. Such cell deaths could act as a source of random change within the nervous system that might not always be deleterious57.
So little attention has been paid to the ageing and death of cells during growth and development, both normal and abnormal, that detailed information about these processes is scarce. Where facts are few, speculation can flourish. Most of the speculations advanced in this article could be opposed by alternative speculations, but they illustrate the view that growth and development cannot be understood in isolation from ageing and death. This is by no means an original concept, but at the cellular level it provides a perspective in which many familiar facts take on a new significance and suggests a new approach to familiar problems.
I am indebted to Dr A. Glücksmann, Dr W Jacobson and Professor E.N. Willmer for helpful comments, criticism and discussion.
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http://www.sheldrake.org/Articles&Papers/papers/ageing/AgeingofCells.html
The Ageing, Growth and Death of Cells
Nature, Vol. 250, No. 5465, pp. 381-385, August 2, 1974
by Rupert Sheldrake
No cell is immortal. If a cell grows and divides, it becomes two cells; if it does not divide, sooner or later it dies. Multicellular organisms are not aggregates of cells in a state of exponential growth and division. Some cells divide, but most differentiate and do not undergo further division. Here I shall discuss the ageing and death of cells in vascular plants and vertebrate animals in an attempt to explore the significance of these processes in relation to growth and development, both normal and abnormal.
It is often convenient to think of cells of living organisms as maintaining a more or less steady state; but it is also easy to forget that this is an approximation, an abstraction which, if realised, would confer on cells and on organisms the doubtful blessings of eternal life and eternal youth. The realities of growth, development, ageing and death cannot be understood in terms of steady state concepts. They are directional and irreversible changes in time.
Some cells die as they differentiate, for example xylem cells in plants and keratinised epidermal cells in animals; some, such as phloem sieve tubes in plants and red blood cells in mammals, lose their nuclei; others which retain their nuclei may lose their ability to divide - as do most nerve cells. But even cells which retain their ability to divide will die if they do not do so; they senesce.
Any general hypothesis of cellular ageing must not only explain cellular ageing itself, but also the way in which some cell lines do not senesce and die out. The germ cell line is continuous from generation to generation (also many plants can be propogated vegetatively indefinitely) and some cell lines derived from plant or animal tissues can be propagated in vitro for an indefinite number of generations.
General hypotheses of ageing based on genetic mutation face two difficulties. First, in explaining the universality of the processes of ageing in non dividing cells in terms of a lethal accumulation of harmful mutations and, second, in accounting for the facts of sexual and vegetative reproduction, which show that mutations do not accumulate to a lethal extent in all cells. The alternative to a genetic-mutation hypothesis of ageing is some sort of 'cytoplasmic' hypothesis, the most recent and best known of which is Orgel's 'error catastrophe' hypothesis, which postulates that an accumulation of errors in protein synthesis leads to a positive feedback of error as the enzymes involved in protein synthesis themselves develop errors and thus produce more defective proteins1. For this hypothesis to account for the continuity of the germ line and the indefinite propagation of 'permanent cell lines' in vitro it is necessary to postulate a process of 'cellular selection' whereby error-containing cells are selected out.
Neither the genetic-mutation hypothesis nor the protein synthesis 'error catastrophe' hypothesis of ageing are supported by sufficient evidence to rule out the possibility that cellular ageing may be explicable in terms of the accumulation of cytoplasmic breakdown products, some of which might be deleterious to the cell if they accumulated sufficiently. In all actively metabolising cells, there is a turn-over of cytoplasmic constituents such as proteins and membrane lipids. More is known about their synthesis than about their breakdown in vivo; while some of them may be broken down completely, others may be broken down only partially or not at all. They must therefore accumulate.
Lipid peroxidation
One example of such an accumulation is provided by the 'age pigment' or lipofuscin granules which accumulate in an age-dependent way in the cells of many mammalian tissues4. The lipofuscin material contains lipid and protein and may be formed in autophagosomal vesicles, for example during the digestion of mitochondria; haem groups, released as the cytochromes are degraded, may catalyse the peroxidation of unsaturated lipids in the degenerating mitochondrial membranes which may cross link with each other and with denatured proteins 6. The cells seem to be unable to destroy these cross-linked polymers. Lipofuscin granules do not seem to damage cells directly except when they accumulate, as they do in certain diseases, to such an extent that they mechanically interfere with the structure and functions of the cell.
Lipid peroxidation does not always result in the formation of microscopically visible lipofuscin granules, nor is it confined to autophagosomal vesicles; it occurs in all functional cell membranes, including the surface membrane. Once the peroxidation of unsaturated lipids is initiated, by haem groups, Fe2+ ions and other simple catalysts in the presence of oxygen, it takes place by a free radical chain reaction. It can be inhibited by lipid-soluble antioxidants such as vitamin E and accelerated by vitamin E deficiency, ionising radiation, chloroform and ethanol poisoning and hyperbaric treatments 8,9, which can cause irreversible damage to cells.
The peroxidation of lipids within cell membranes is occurring in vivo all the time. Some peroxidised lipids may be metabolised but others, perhaps those which are cross linked to other lipids and lipoproteins may not be. The chain reaction of lipid peroxidation may be terminated by the oxidation of other substances which may themselves be damaged and accumulate. Such substances formed within the surface membrane, for example, may accumulate in situ; if they are removed from the surface membrane as the membrane is recycled by the invagination of membrane vesicles11-14 or by other means, some of them might find their way into residual bodies, but they might also be incorporated into intracellular membranes. The formation and accumulation of such substances within the outer and intracellular membranes, for example in the Golgi apparatus, endoplasmic reticulum nuclear membrane and lysosomal membranes, could well be deleterious to normal membrane functioning and could also lead to a positive feedback of damage by further lipid peroxidation, and thus to the senescence and death of the cell. The rate of ageing would be temperature dependent and would also depend on the composition, structure and functions of the cellular membranes, the extra - and intracellular environments, antioxidant levels and so on. Thus, different types of cells would age at different rates but, according to this hypothesis, all cells would be ageing to a greater or lesser extent all the time; all cells would be heading towards senescence and death.
The elimination of membranous material from cells might enable the ageing process to be retarded and there are a few examples of the shedding of membranes by cells which I will discuss further. But, in general, the only way in which cells could avoid their otherwise inevitable mortality would be by growing and dividing, thus diluting the accumulated breakdown products. Although lipid peroxidation may be the most important cause of the formation of such substances, the following general considerations could apply to any deleterious substances which accumulate with age.
Growth and division of cells
An artificially simple case is provided by cells dividing symmetrically with a fixed generation time if these accumulate deleterious breakdown products linearly with time, an amount, x, being formed per cell generation time. Successive generations contain more of the accumulated breakdown products but the increments become smaller and smaller. If the rate of accumulation is not linear, but proportional to the amount already accumulated, the content per cell will increase exponentially; and if there is a progressive lengthening of the cell generation time, there will be a greater accumulation within individual cells in succeeding generations. With either or both of these assumptions, it can be seen that the whole population will undergo senescence and sooner or later die out.
But another type of cell division is possible, an asymmetrical division in which one of the daughter cells receives all or most of the accumulated breakdown products (becoming more 'mortal') while the other is rejuvenated, receiving little or none. The more 'mortal' of the daughter cells might die or differentiate directly, or it might divide again unequally, producing a rejuvenated cell and a cell even more 'mortal' than itself, or it might undergo one or more sequential symmetrical divisions (as discussed above) to produce a population of cells which sooner or later die (unless they can undergo further asymmetrical divisions to produce rejuvenated cells).
I shall now consider a few aspects of the growth and development of higher plants and higher animals in the light of these ideas. Dicotyledonous trees illustrate the pattern of indefinite growth that is characteristic of plants. (There are of course plants, such as herbaceous annuals, which die after they have flowered. But annuals are capable of growing for much longer than their normal life-span if they are prevented from flowering, indicating that they die because they flower and not because of an innate inability to go on growing15.) The life span of trees is limited by a variety of mechanical factors, but cuttings taken from old trees can give rise to healthy young trees, and this process can be repeated indefinitely. The growing points of the tree, the apical meristems, remain perpetually young.
Cell divisions within the apical meristems of the shoots give rise to daughter cells with different fates: some remain meristematic, others give rise to the differentiated structures of the stems and the leaves. Some of these cells die as they differentiate into vascular tissues and fibres, others, for example the leaf mesophyll and pith parenchyma, remain alive for some time, but, unless they are stimulated to divide again in a regenerative response to wounding or damage, they eventually die. The leaves senesce and fall from the tree; the pith breaks down. The root meristems give rise to the primary tissues of the root which, apart from those which divide to produce further root meristems, sooner or later die. In secondarily thickening stems the divisions of the cambial cells give rise to cells which die as they differentiate into xylem or undergo further asymmetrical divisions to produce phloem companion cells and sieve tubes. These cells eventually die and are sloughed off in the bark. Cell divisions in the cork cambium give rise to cork cells which die as they differentiate; divisions of the root cap initials give rise to root cap cells which die and are sloughed off. Thus, in the various meristems of the plant the continued growth and continued rejuvenation of the meristems is associated with the production of cells which die during or after differentiation.
Vertebrates
Vertebrates, unlike trees, do not go on growing indefinitely, nor can they be propagated vegetatively. At first, fertilised eggs undergo cleavages which rapidly increase the number of cells, but this rate of increase of cell number declines progressively as the animal develops, and as cells and tissues differentiate16. Throughout the development of the embryo many tissues and groups of cells regress and die17,18. Some of these cell deaths are associated with tissue differentiation19, some occur during morphogenetic processes20, and others may represent the regression of phylogenetically vestigial structures17, but the significance of other cell deaths is obscure. As the animal develops, the cells of some tissues, such as nerve and muscle, differentiate and to a large extent lose the ability to undergo further division. Some of these cells die as the animal grows older and are not replaced21,22 but in the adult animal a number of other tissues continue to grow, for example the epidermis, the intestinal lining, the liver and blood cells continue to be formed. In all these examples the production of new cells is offset by cell death. Cell divisions in the basal layers of the mammalian epidermis give rise to daughter cells which remain in the basal layers and divide again, and other daughter cells which differentiate and keratinise, dying as they do so. Cell divisions in the crypts of the intestinal villi replenish the population of crypt cells capable of further division and produce other daughter cells which move up the villi where they die and are sloughed off23. Asymmetrical divisions of the early precursors of all cells of the blood occur throughout life and give rise to further precursor cells as well as to the maturing and mature cells of the blood, all of which have a limited life span. During the formation of red blood cells24 and granulocytes25 in the bone marrow, and lymphocytes in the thymus26, considerable numbers of cells die in situ soon after they are formed. The reasons for this 'ineffective' erythropoiesis, granulopoiesis and lymphopoiesis are unknown.
The mortality of at least some of the cells which die in developing animal embryos and in mature animals may represent the price that is paid for the rejuvenation of other cells which continue to grow and divide. But unfortunately too little is known about cell lineages in animals, especially in embryos, for it to be possible to decide how general is the phenomenon of asymmetrical cell divisions giving rise to daughter cells of unequal mortality. The recognition of this pattern is complicated by the fact that by no means all cell death takes place as a result of cellular senescence. Some cells die as they differentiate and others may die because they find themselves in the wrong places at the wrong times19. Cell deaths may be controlled chemically, for example by steroid hormones: the injection of glucocorticoids can cause large numbers of lymphocytes to die27, the regression of Mullerian and Wolffian ducts is controlled by androgens and oestrogens19,28 and the regression of the lining of the female genital tract is under the control of oestrogens28. But, under the hypothesis that asymmetrical cell divisions lead to a rejuvenation of 'meristematic' daughter cells at the price of the increased mortality of their sister cells, it does not matter whether the latter die as a result of senescence, or whether they die as they differentiate or for any other reason.
Sexual reproduction
In the sexual reproduction of both higher plants and higher animals almost all the cytoplasm from which the embryo and the new organism develops is provided by the egg. In both cases, the egg cells are formed as a result of asymmetrical divisions of the egg mother cell. In the great majority of higher plants, the meiotic divisions of the egg mother cell produce four cells, three of which die. The fourth undergoes further divisions to produce the cells of the embryo sac, most of which die before or shortly after fertilisation. In some species, one of more of the three sister cells of the cell which gives rise to the egg may undergo further division to produce short-lived embryo sac cells29. In animals the first and second meiotic divisions of the egg mother cell give rise to the first and second polar bodies, which regress and die.
It is particularly striking that in both plants and animals, only one of the progeny of the egg mother cell gives rise to an egg while the sister cells die (or if they divide give rise to short-lived progeny). By contrast, there is no comparable cell loss in male gametogenesis associated with the meiotic divisions of the pollen mother cells and spermatogonia.
The many examples in both higher plants and higher animals (and many more can be found in the lower plants and lower animals) of the production of rejuvenated meristematic, stem or egg cells by asymmetrical divisions do not of course prove that these divisions involve an asymmetrical distribution of deleterious breakdown products; but the available facts appear to be consistent with this hypothesis.
Loss of membranous material by animal cells
If the accumulation of deleterious breakdown products of membrane lipids is one of the causes of cellular senescence, the loss of membranous material might be of considerable importance in enabling cells to rid themselves of such substances. The shedding of membranous material by living cells does not seem to be of common occurrence but can take place in mammalian cells as follows.
First, in apocrine secretions part of the cell membrane is lost. The best example, and the only one for which conclusive ultrastructural evidence exists, is in the secretion of lipid droplets by the cells of lactating mammary glands. The secreted lipid droplets are surrounded by a unit membrane derived in part from the surface membrane and in part from Golgi vesicle membranes.
Second, membrane-bounded vesicles of cytoplasm can break away from mammalian macrophages both in vitro and in vivo. This process, known as clasmotosis, is of unknown significance. Lymphocytes which are activated in immunological reactions or as a result of phytohaemagglutinin stimulation form 'tails' (uropods) which can bleb off vesiculated buds in vivo and in vitro. Again, the significance of this process is unknown. Clasmotosis is also frequently observed in cultures of fibroblasts.
Third, many types of animal viruses are budded off from host cells in membrane-bounded vesicles. The protein in the membrane of the vesicles is largely viral, at least in the case of RNA tumour viruses, but the lipids are derived from the host cell membrane35. Viral particles bounded by membrane are also budded off from the cells of a number of spontaneously cancerous tissues and from many of the cell strains and permanent cells lines which are commonly cultured in laboratories.
Tissue cultures
Many plants callus cultures can be grown indefinitely in vitro. During the early stages of the growth of some calluses, an exponential increase in cell number takes place at a rate which suggests that many of the cells may undergo a limited number of sequential symmetrical divisions before the growth rate declines but in most plant tissue cultures the rate of increase of cell number is more or less linear for most of the growth period39,40. Linear growth characteristics would be compatible with a meristematic pattern of cell division such that some daughter cells continue to grow and divide while their sister cells age and sooner or later die. Unfortunately nothing is known in detail about cell lineages within these cultures, nor are there any quantitative data on cell death. Nevertheless, dead and dying cells are by no means uncommon.
'Permanent' mammalian cell lines capable of indefinite propagation in vitro can be derived from cancerous tissues and also from cells which have undergone a spontaneous 'transformation' during culture. Diploid fibroblast cultures can be propagated, however, only for a finite number of subculturings, more (up to about 60) if the cells are derived from embryonic tissues, fewer if they are derived from mature organisms41. The number of generations through which the cells can be passed before the population senesces and dies out is reduced if the period of time between the subculturings is increased42. Fibroblasts of the mouse L strain have been observed to divide symmetrically over six to seven cell generations with a more or less constant generation time43; if the cells in the diploid fibroblast cultures also divide symmetrically, deleterious breakdown products might accumulate in the cells of succeeding generations, as discussed above, and account for the senescence of these cultures. It is impossible, however, to make any detailed interpretation of the senescence of these cultures in the absence of quantitative information about the proportions of dividing and nondividing cells, the incidence of cell death, and the extent and significance of clasmotosis within these cultures - or indeed with cultures of 'transformed' and 'permanent' cell lines.
Cancer
Malignancy must not only involve the freeing of cells from the normal controls on their proliferation, but also the avoidance of senescence by at least a part of the cell population. Many animal tumours contain a stem cell or 'meristematic' population which gives rise to daughter cells which may or may not differentiate, but which sooner or later die. There are numberous examples of cell death within cancerous tissues45-48. Some of the cell deaths can be explained in terms of an inadequate vascularisation of the tumour tissue, but in most tumours this is by no means the only cause an does not apply to all to leukaemias; many of the cells may die as a result of ageing.
Little attention has been paid to the incidence of cell death within cultures of cancerous cells and it is therefore at present impossible to know to what extent the patterns of cell division, ageing and death within these cultures resemble those within in vivo cancers. It is sometimes assumed, if only implicitly, that overall exponential growth characteristics of cell cultures mean that there is a homogeneous population of symmetrically dividing cells. This assumption is not justified: a heterogeneous population containing proliferating, nonproliferating and dying cells can also grow exponentially if the proportion of cells that die is constant with time.
It is conceivable that the loss of membranous material either spontaneously, as in certain types of mammary gland tumours, or as a result of the budding off of viruses (such as RNA tumour viruses) could play a significant role in the retardation of cellular senescence in certain types of cancer.
Effects of cell death
Very little is known about the biochemistry of dying cells. Such cells probably release all sorts of proteins, glycoproteins, peptides, amino acids, amino acid breakdown products, nucleic acids and nucleic acid breakdown products, lipids and lipid breakdown products as well as salts and other substances which were sequestered inside the cells.
It has recently been found that in higher plants the hormone auxin (indole-3-acetic acid) is formed as a consequence of cell death as tryptophan, released by proteolysis, is broken down. Dying cells in differentiating vascular tissue, regressing nutritive tissues and so on, are probably the major source of this hormone within the plant52. Other plant hormones may also be produced by damaged and dying cells: ethylene from the breakdown of methionine and cytokinins by the hydrolysis of transfer RNA. In higher plants the normal production of hormones as a consequence of cell death and the production of 'wound hormones' by damaged cells can be seen as two aspects of the same phenomenon.52
Wound and regenerative responses in vertebrates cannot be explained simply in terms of wound hormones, but there is evidence that dying cells release substances that stimulate phagocytosis53, and affect growth and development in both normal54,55 and cancerous tissues56. And at least some of the cell deaths which occur during normal embryonic development may well result in the production or release of substances involved in the control of differentiation and development.
Dying cells may not only have a chemical effect on neighbouring cells but also a physical effect as cell to cell contacts are broken. Cell deaths within a tissue may also affect the functioning of the tissue as a whole: for example, the death of nerve cells within the brain22 seems likely to affect pathways or patterns of nervous conduction, perhaps leading to the formation of new pathways or patterns. Such cell deaths could act as a source of random change within the nervous system that might not always be deleterious57.
So little attention has been paid to the ageing and death of cells during growth and development, both normal and abnormal, that detailed information about these processes is scarce. Where facts are few, speculation can flourish. Most of the speculations advanced in this article could be opposed by alternative speculations, but they illustrate the view that growth and development cannot be understood in isolation from ageing and death. This is by no means an original concept, but at the cellular level it provides a perspective in which many familiar facts take on a new significance and suggests a new approach to familiar problems.
I am indebted to Dr A. Glücksmann, Dr W Jacobson and Professor E.N. Willmer for helpful comments, criticism and discussion.
References
1 Orgel, L.E., Proc. natn. Acad. Sci. U.S.A., 49, 517-521 (1963).
2 Orgel, L.E., Nature, 243, 441-445 (1973).
3 Smith, J.M., Proc. R. Soc., B., 157, 115-127 (1963).
4 Strehler, B.L., Adv. gerontol. Res., 1, 343-384 (1964).
5 Goldfisher, S., Villaverde, H., and Forschirm, R., J. Histochem. Cytochem, 14, 641-652 (1966).
6 Bjorkend, S., Adv. gerontol. Res., 1, 257-288 (1964).
7 Zemen, W., Adv. gerontol. Res., 3, 147-170 (1971).
8 Barber, A. A., and Bernheim, F., Adv. gerontol. Res., 2, 355-403 (1967).
9 Slater, T. F., Free Radical Mechanisms in Tissue Injury (Pion Ltd., London, 1972).
10 Dormandy, T. L., Lancet, ii, 684-688 (1969).
11 Abraham, S. J., and Holtzman, E., J Cell Biol., 56, 540-558 (1973).
12 Geuze, J. G., and Pont, C., J Cell Biol., 57, 159-174 (1973).
13 Heuser, J. E., and Reese, T. S., J Cell Biol., 57, 315-344 (1973).
14 Orci, L., Malisse-Lagae, F., Ravazzola, M., and Amherdt, M., Science, 181, 561-562 (1973).
15 Priestley, J. H., and Scott, L. I., An Introduction to Botany (Longmans, Green and Co., London, 1938).
16 Minot, C.S., The Problem of Age, Growth and Death (John Murray, London, 1908).
17 Glücksmann, A., Biol. Rev., 26, 59-86 (1951).
18 Menkes, B., Sandor, S., and Ilies, A., Adv. Teratol., 4, 169-215 (1970).
19 Glücksman, A., Archs Biol., 76, 419-437 (1965).
20 Saunders, J. W., Science, 154, 604-612 (1966).
21 Broun, W. F., J Neurol. Neurosurg. Psychiat., 35, 845-852 (1972).
22 Brody, H., J. compl Neurol., 102, 511-556 (1955).
23 Quastler, H., and Sherman, F. G., Expl Cell Res., 17, 420-438 (1959).
24 Harris, J. W., and Kellermeyer, R. W., The Red Cell (Harvard University Press, Cambridge, Mass., 1970).
25 Maloney, M. A., Patt, H. M., and Lund, J. E., Cell Tissue Kinet., 4, 201-209 (1971).
26 Metcalf, D., in The Thymus (edit. by Wolstenholme, G. E. W., and Porter, R.), 242-263 (Churchill, London, 1966).
27 Pushin, R. W., and Harven, E., J. Cell Biol., 50, 583-597 (1971).
28 Biggers, J. D., in Cellular Injury (edit. by de Reuck, A. V. S., and Knight, J.), 329-349 (Churchill, London, 1964).
29 Maheshwari, P., An Introduction to the Embryology of the Angiosperms (McGraw Hill, New York, 1950).
30 Odor, D. L., Am. J. Anat., 97, 461-492 (1955).
31 Odor, D. L., and Renninger, D. F., Anat. Rec., 137, 13-23 (1960).
32 Wooding, F. B. P., J. Cell. Sci., 9, 805-821 (1971).
33 Jacoby, F., in Cells and Tissues in Culture, II (edit. by Willmer, E. N.), 1-93 (Academic Press, London, 1965).
34 Biberfield. P., Expl Cell Res., 66, 433-445 (1971).
35 Blough, H. A., and Tiffany, J. M., Adv. Lipid Res., 11, 267-239 (1973).
36 Gross. L., Oncogenic Viruses 2nd ed. (Pergamon Press, Oxford, 1970).
37 Lieber, M. M., Benveniste, R. E., Livingston, D. M., and Todaro, G. J., Science, 182, 56-59 (1973).
38 Sunderland, N., Ann. Bot., 31, 573-591 (1967).
39 Street, H. E., King, P. J., and Mansfield, K. J., in (Colloques Internationaux du Centre National de la Récherche Scientifique No. 193), 17-40 (CNRS, Paris, 1971).
40 Short, K. C., and Torrey, J. G., J exp. Bot., 23, 1099-1105 (1972).
41 Hayflick, L, Expl Cell Res., 37, 614-636 (1965).
42 McHale, J. S., Mouton, M. L., and McHale, J. T., Expl. Geront., 6, 89-93 (1971).
43 Miyamoto, H., Zeuthen, E., and Rasmussen, L., J. Cell Sci., 13, 879-888 (1973).
44 Bullough, W. S., and Deol., J. U. R., Symp. Soc. exp. Biol., 25, 255-275 (1971).
45 Glücksmann, A., in Recent Advances in Clinical Pathology (edit. by Dyke, S. C.), 338-349 (Churchill, London, 1947).
46 Cooper, E. H., Cell Tissue Kinet., 6, 87-95 (1973).
47 Kerr, J. F. R., and Searle, J., J. Path., 107, 41-44 (1972).
48 Kerr, J. F. R., Wyllie, A. H., and Currie, A. R., Br. J. Cancer, 26, 239-257 (1972).
49 Steel, G. G., Cell Tissue Kinet., 1, 193-207 (1968).
50 Gavosto, F., and Pileri, A., in The Cell Cycle and Cancer (edit. by Baserga, R.) (Dekker, New York, 1971).
51 Tarin, D., Br.J. Cancer, 23, 417-425 (1969).
52 Sheldrake, A. R., Biol. Rev., 48, 508-559 (1973).
53 Bessis, M., in Cellular Injury (edit. by de Reuck, A. V. S., and Knight, J.), 287-316 (Churchill, London, 1964).
54 Majno, G., in Cellular Injury (edit. by de Reuck, A. V. S., and Knight, J.), 87-98 (Churchill, London, 1964).
55 Teir, H., Lahtiharju, A., Alho, A., and Forsell, K-J, in Control of Cellular Growth in Adult Organisms (edit. by Tier, H., and Rytömaa, T.), 67-82 (Academic Press, London, 1967).
56 Vasiliev, J. M., and Guelstein, V. I., Prog. exp. Tumor Res., 8, 26-65 (1966).
57 Sheldrake, A. R., Theoria to Theory, 7, (3) 31-38 (1973)
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Morphic resonance : A Telephathic Cat?
Rupert Sheldrake, one of the world’s most innovative biologists and writers is best known for his theory of morphic fields and morphic resonance, which leads to a vision of a living, developing universe with its own inherent memory. |  |
He first worked in developmental biology at Cambridge University, and is currently Director of the Perrott-Warrick project. Rupert Sheldrake... Biography A Guide to the Website Rupert's Science and Philosophy | |
Are the laws of nature more like habits?
A summary of the hypothesis of Morphic Resonance.
Who owns the moon?
I personally think humans are FOOLISH to want to own everything!
"1:03:33 - 1 year ago
Steve Durst and William Marshall speak about property rights and ownership of Earth's Moon at a NASA CoLab Luna Philosophie. Presented on August 20, 2008 at the Yahoo! Brickhouse in San Francisco, California.""1:03:33 - 1 year ago
Monday, July 19, 2010
The Philosophy of Liberty
The philosophy of liberty is based on self-ownership. This simple but elegant and hard-hitting animation will explain exactly what that means. It's a great tool anyone can use to educate children and adults about our right to life, liberty, and the property we create - and our responsibility to think, speak and act.
For more info and/or to download a free DVD version of this video, see:
http://www.philosophyofliberty.blogsp...
CREDITS
AUTHOR: Ken Schoolland schoolak001@hawaii.rr.com
PRODUCER: Kerry Pearson (aka Lux Lucre)
MUSIC: Music2Hues 'Betrayal' http://www.music2hues.com/m2h_orig/fl...
WEBSITE: http://www.jonathangullible.com
SUPPORT: The Jonathan Gullible fund http://www.isil.org/tools/jonathan-gu...
COPYRIGHT: http://www.creativecommons.org/licens...
For more info and/or to download a free DVD version of this video, see:
http://www.philosophyofliberty.blogsp...
CREDITS
AUTHOR: Ken Schoolland schoolak001@hawaii.rr.com
PRODUCER: Kerry Pearson (aka Lux Lucre)
MUSIC: Music2Hues 'Betrayal' http://www.music2hues.com/m2h_orig/fl...
WEBSITE: http://www.jonathangullible.com
SUPPORT: The Jonathan Gullible fund http://www.isil.org/tools/jonathan-gu...
COPYRIGHT: http://www.creativecommons.org/licens...
Sunday, July 18, 2010
A Classroom Divided
55:16 minutes
One day in 1968, Jane Elliott, a teacher in a small, all-white Iowa town, divided her third-grade class into blue-eyed and brown-eyed groups and gave them a daring lesson in discrimination. This is the story of that lesson, its lasting impact on the children, and its enduring power thirty years later.
One day in 1968, Jane Elliott, a teacher in a small, all-white Iowa town, divided her third-grade class into blue-eyed and brown-eyed groups and gave them a daring lesson in discrimination. This is the story of that lesson, its lasting impact on the children, and its enduring power thirty years later.
Thursday, July 15, 2010
Wednesday, July 14, 2010
Tuesday, July 13, 2010
Chinese characters
A Chinese character, also known as a Han character (汉字 / 漢字; Hànzì), is a logogram used in writing Chinese (hanzi), Japanese (kanji), less frequently Korean (hanja), and formerly Vietnamese (hán tự), and other languages. Chinese characters are also known as sinographs, and the Chinese writing system as sinography. Chinese characters represent the oldest continuously used system of writing in the world.[1][2][3]
The number of Chinese characters contained in the Kangxi dictionary is approximately 47,035, although a large number of these are rarely used variants accumulated throughout history. Studies carried out in China have shown that full literacy in the Chinese language requires a knowledge of only between three and four thousand characters.[4]
In the Chinese writing system, the characters are monosyllabic, each usually corresponding to a spoken syllable with a basic meaning. However, although Chinese words may be formed by characters with basic meanings, a majority of words in Mandarin Chinese require two or more characters to write (thus are polysyllabic) but have meaning that is distinct from but dependent on the characters they are made from.[5] Cognates in the various Chinese languages/dialects which have the same or similar meaning but different pronunciations can be written with the same character.
Chinese characters have also been used and in some cases continue to be used in other languages, most significantly Japanese (where a single character can represent several spoken syllables), Korean, and Vietnamese. Chinese characters are used both by meaning to represent native words, ignoring the Chinese pronunciation, and by meaning and sound, to represent Chinese loanwords. These foreign pronunciations of Chinese characters are known as Sinoxenic pronunciations, and have been useful in the reconstruction of Ancient Chinese.
However, because these marks occur singly, without any context to imply, and because they are generally extremely crude and simple, Qiú Xīguī (2000, p. 31) concluded that "we do not have any basis for stating that these constituted writing, nor is there reason to conclude that they were ancestral to Shang dynasty Chinese characters." Isolated graphs and pictures continue to be found periodically, frequently accompanied by media reports pushing back the purported beginnings of Chinese writing a few thousand years. For example, at Damaidi in Ningxia, 3,172 pictorial cliff carvings dating to 6000–5000 BC have been discovered, leading to headlines such as "Chinese writing '8,000 years old.'"[6] Similarly, archaeologists report finding a few inscribed symbols on tortoise shells at the Neolithic site of Jiahu in Henan, dated to around 6,600–6,200 BCE, leading to headlines of "'Earliest writing' found in China.[7]
In his comment released to the BBC, Professor David Keightley urged caution in the latter instance, pointing to the lack of any direct cultural connection to Shāng culture, combined with gaps between them of many millennia. However, in the same BBC article, a supporting argument is provided by Dr Garman Harbottle, of the Brookhaven National Laboratory in New York, US, who collaborated with a team of archaeologists at the University of Science and Technology of China, in Anhui province in the discovery. Dr Harbottle points to the persistence of sign use at different sites along the Yellow River throughout the Neolithic and up to the Shāng period, when a complex writing system appears.[7]
One group of sites of interest is the Dàwènkǒu culture sites (2800–2500 BCE, only one millennium earlier than the early Shāng culture sites, and positioned so as to be plausibly albeit indirectly ancestral to the Shāng). There, a few inscribed pottery and jade pieces have been found,[8] one of which combines pictorial elements (resembling, according to some, a sun, moon or clouds, and fire or a mountain) in a stack which brings to mind the compounding of elements in Chinese characters. Major scholars are divided in their interpretation of such inscribed symbols. Some, such as Yú Xǐngwú,[9] Táng Lán[10] and Lǐ Xuéqín,[11] have identified these with specific Chinese characters. Others such as Wang Ningsheng[12] interpret them as pictorial symbols such as clan insignia, rather than writing. But in the view of Wang Ningsheng, "True writing begins when it represents sounds and consists of symbols that are able to record language. The few isolated figures found on pottery still cannot substantiate this point."[13]
The oldest Chinese inscriptions that are indisputably writing are the Oracle bone script (甲骨文 jiǎgǔwén, literally "shell-bone-script"). These were identified by scholars in 1899 on pieces of bone and turtle shell being sold as medicine, and by 1928, the source of the oracle bones had been traced back to modern Xiǎotún (小屯) village at Ānyáng in Hénán Province, where official archaeological excavations in 1928–1937 discovered 20,000 oracle bone pieces, about 1/5 of the total discovered. The inscriptions were records of the divinations performed for or by the royal Shāng household. The oracle bone script is a well-developed writing system, attested from the late Shang Dynasty (1200–1050 BC).[14][15][16] Only about 1,400 of the 2,500 known oracle bone script logographs can be identified with later Chinese characters and thus deciphered by paleographers.
Left: Bronze fāngzūn (方樽) ritual wine container dated about 1000 BCE. The written inscription cast in bronze on the vessel commemorates a gift of cowrie shells (then used as currency in China) from someone of presumably elite status in Zhou Dynasty society. Right: Bronze fāngyí (方彝) ritual container dated about 1000 BCE. A written inscription of some 180 Chinese characters appears twice on the vessel. The written inscription comments on state rituals that accompanied court ceremony, recorded by an official scribe.Based on studies of such bronze inscriptions, it is clear that from the Shāng dynasty writing to that of the Western Zhōu and early Eastern Zhōu, the mainstream script evolved in a slow, unbroken fashion, until taking the form now known as seal script in the late Eastern Zhōu in the state of Qín, without any clear line of division.[18][19] Meanwhile other scripts had evolved, especially in the eastern and southern areas during the late Zhōu, including regional forms, such as the gǔwén “ancient forms” of the eastern Warring States preserved in the Hàn dynasty etymological dictionary Shuōwén Jiézì as variant forms, as well as decorative forms such as bird and insect scripts.
There are numerous styles, or scripts, in which Chinese characters can be written, deriving from various calligraphic and historical models. Most of these originated in China and are now common, with minor variations, in all countries where Chinese characters are used. These characters were used over 3,000 years ago.
The Shang dynasty Oracle Bone and Zhou dynasty scripts found on Chinese bronze inscriptions being no longer used, the oldest script that is still in use today is the Seal Script (篆书 / 篆書 zhuànshū). It evolved organically out of the Spring and Autumn period Zhou script, and was adopted in a standardized form under the first Emperor of China, Qin Shi Huang. The seal script, as the name suggests, is now only used in artistic seals. Few people are still able to read it effortlessly today, although the art of carving a traditional seal in the script remains alive; some calligraphers also work in this style.
Scripts that are still used regularly are the "Clerical Script" (隶书 / 隸書 lìshū) of the Qin Dynasty to the Han Dynasty, the Weibei (Chinese: 魏碑; pinyin: wèibēi), the "Regular Script" (楷书 / 楷書 kǎishū) used mostly for printing, and the "Semi-cursive Script" (行书 / 行書 xíngshū) used mostly for handwriting.
The Cursive Script (草书 / 草書 cǎoshū, literally "grass script") is not in general use, and is a purely artistic calligraphic style. The basic character shapes are suggested, rather than explicitly realized, and the abbreviations are extreme. Despite being cursive to the point where individual strokes are no longer differentiable and the characters often illegible to the untrained eye, this script (also known as draft) is highly revered for the beauty and freedom that it embodies. Some of the Simplified Chinese characters adopted by the People's Republic of China, and some of the simplified characters used in Japan, are derived from the Cursive Script. The Japanese hiragana script is also derived from this script.
There also exist scripts created outside China, such as the Japanese Edomoji styles; these have tended to remain restricted to their countries of origin, rather than spreading to other countries like the scripts described above.
"Han unification" was completed for the purposes of Unicode in 1991 (Unicode 1.0).
Excerpt from a 1436 primer on Chinese charactersThe earliest known Chinese texts, in the Oracle bone script, display a fully developed writing system, with little difference in functionality from modern characters. It is assumed that the early stages of the development of characters were dominated by pictograms, which were the objects depicted, and ideograms, in which meaning was expressed iconically. The demands of writing full language, including words which had no easy pictographic or iconic representation, forced an expansion of this system, presumably through use of rebus.
The presumed methods of forming characters were first classified c. 100 AD by the Chinese linguist Xu Shen, whose etymological dictionary Shuowen Jiezi (说文解字 / 說文解字) divides the script into six categories, the liùshū (六书 / 六書). While the categories and classification are occasionally problematic and arguably fail to reflect the complete nature of the Chinese writing system, this account has been perpetuated by its long history and pervasive use.[42]
Four percent of Chinese characters are derived directly from individual pictograms, though in most cases the resemblance to an object is no longer clear. Others are ideograms, compound ideograms, where two ideograms are combined to give a third reading, or rebus. But most characters are phono-semantic compounds, with one element to indicate the general category of meaning and the other to suggest the pronunciation. Again, in many cases the suggested sound is no longer accurate.
There is no concrete number for the proportion of modern characters that are pictographic in nature; however, Xu Shen (c. 100 AD) estimated that 4% of characters fell into this category.
Xu Shen estimated that 13% of characters fall into this category.
Some scholars flatly reject the existence of this category, opining that failure of modern attempts to identify a phonetic in a compound is due simply to our not looking at ancient "secondary readings", which were lost over time.[45] For example, the character 安 ān "peace", a combination of "roof" 宀 and "woman" 女, is commonly cited as an ideogrammic compound, purportedly motivated by a meaning such as "all is peaceful with the woman at home". However, there is evidence that 女 was once a polyphone with a secondary reading of *an, as may be gleaned from the set 妟 yàn "tranquil", 奻 nuán "to quarrel", and 姦 jiān "licentious". Supporting this reasoning is the fact that modern interpretations often neglect archaic forms that were in use when the characters were created.
These arguments notwithstanding, there are some characters that do appear to genuinely belong to this category. It is doubtful that secondary readings can be found for many cases, and the characters 林, 森, 明, 休, and 好 are all attested in oracle bone script, with the same components as the modern forms.
Examples are 河 hé "river", 湖 hú "lake", 流 liú "stream", 沖 chōng "riptide" (or "flush"), 滑 huá "slippery". All these characters have on the left a radical of three short strokes, which is a simplified pictograph for a river, indicating that the character has a semantic connection with water; the right-hand side in each case is a phonetic indicator. For example, in the case of 沖 chōng (Old Chinese /druŋ/[46]), the phonetic indicator is 中 zhōng (Old Chinese /truŋ/[47]), which by itself means "middle". In this case it can be seen that the pronunciation of the character is slightly different from that of its phonetic indicator; this process means that the composition of such characters can sometimes seem arbitrary today. Further, the choice of radicals may also seem arbitrary in some cases; for example, the radical of 貓 māo "cat" is 豸 zhì, originally a pictograph for worms,[citation needed] but in characters of this sort indicating an animal of any sort.
Xu Shen (c. 100 CE) placed approximately 82% of characters into this category, while in the Kangxi Dictionary (1716 CE) the number is closer to 90%, due to the extremely productive use of this technique to extend the Chinese vocabulary.
This method is still sometimes used to form new characters, for example 钚 bù "plutonium") is the metal radical 金 jīn plus the phonetic component 不 bù, described in Chinese as "不 gives sound, 金 gives meaning". Many Chinese names of elements in the periodic table and many other chemistry-related characters were formed this way.
Despite standardization, some nonstandard forms are commonly used, especially in handwriting.
Mainland China adopted simplified characters in 1956, but Traditional Chinese characters are still used in Hong Kong, Macau and Taiwan. Singapore has also adopted Simplified Chinese characters. Postwar Japan has used its own less drastically simplified characters, Shinjitai, since 1946, while South Korea has limited its use of Chinese characters, and Vietnam and North Korea have completely abolished their use in favour of romanized Vietnamese and Hangul, respectively.
The standard character forms of each region are described in:
Microsoft JhengHei is a sans-serif typeface intended for onscreen use. 
A page from a Song Dynasty publication in a regular script typeface which resembles the handwriting of Ouyang Xun.There are three major families of typefaces used in Chinese typography:
Ming and sans-serif are the most popular in body text and are based on regular script for Chinese characters akin to Western serif and sans-serif typefaces, respectively. Regular script typefaces emulate regular script.
The Song typeface (宋体 / 宋體, sòngtǐ) is also known as Minchō (明朝) in Japan and Ming typeface (明体 / 明體, míngtǐ) in Taiwan and Hong Kong. The names of these styles come from the Song and Ming dynasties, when block printing flourished in China. Because the wood grain on printing blocks ran horizontally, it was fairly easy to carve horizontal lines with the grain. However, carving vertical or slanted patterns was difficult because those patterns intersect with the grain and break easily. This resulted in a typeface that has thin horizontal strokes and thick vertical strokes[citation needed]. To prevent wear and tear, the ending of horizontal strokes are also thickened[citation needed]. These design forces resulted in the current Ming typeface characterized by thick vertical strokes contrasted with thin horizontal strokes; triangular ornaments at the end of single horizontal strokes; and overall geometrical regularity.
Sans-serif typefaces, called black typeface (黑体 / 黑體, hēitǐ) in Chinese and Gothic typeface (ゴシック体) in Japanese, are characterized by simple lines of even thickness for each stroke, akin to sans-serif styles such as Arial and Helvetica in Western typography. This group of typefaces, first introduced on newspaper headlines[citation needed], is commonly used where legibility and neutrality is desired.
Regular script typefaces are also commonly used, but not as common as Ming or sans-serif typefaces for body text. Regular script typefaces are often used to teach students Chinese characters, and often aim to match the standard forms of the region where they are meant to be used. Most typefaces in the Song Dynasty were regular script typefaces which resembled a particular person's handwriting (e.g. the handwriting of Ouyang Xun, Yan Zhenqing, or Liu Gongquan), while most modern regular script typefaces tend toward anonymity and regularity.
Although most often associated with the PRC, character simplification predates the 1949 communist victory. Caoshu, cursive written text, almost always includes character simplification, and simplified forms have always existed in print, albeit not for the most formal works. In the 1930s and 1940s, discussions on character simplification took place within the Kuomintang government, and a large number of Chinese intellectuals and writers have long maintained that character simplification would help boost literacy in China. Indeed, this desire by the Kuomintang to simplify the Chinese writing system (inherited and implemented by the CCP) also nursed aspirations of some for the adoption of a phonetic script, in imitation of the Roman alphabet, and spawned such inventions as the Gwoyeu Romatzyh.
The PRC issued its first round of official character simplifications in two documents, the first in 1956 and the second in 1964. A second round of character simplifications (known as erjian, or "second round simplified characters") was promulgated in 1977. It was poorly received, and in 1986 the authorities rescinded the second round completely, while making six revisions to the 1964 list, including the restoration of three traditional characters that had been simplified: 叠 dié, 覆 fù, 像 xiàng.
Many of the simplifications adopted had been in use in informal contexts for a long time, as more convenient alternatives to their more complex standard forms. For example, the orthodox character 來 lái ("come") was written with the structure 来 in the clerical script (隶书 / 隸書, lìshū) of the Han dynasty. This clerical form uses one less stroke, and was thus adopted as a simplified form. The character 雲 yún ("cloud") was written with the structure 云 in the oracle bone script of the Shāng dynasty, and had remained in use later as a phonetic loan in the meaning of "to say" while the the 雨 radical was added to differentiate meanings. The Simplified form adopts the original structure.
Malaysia started teaching a set of simplified characters at schools in 1981, which were also completely identical to the Mainland China simplifications. Chinese newspapers in Malaysia are published in either set of characters, typically with the headlines in Traditional Chinese while the body is in Simplified Chinese.
Although in both countries the use of simplified characters is universal among the younger Chinese generation, a large majority of the older Chinese literate generation still use the traditional characters. Chinese shop signs are also generally written in traditional characters.
Note: this table is merely a brief sample, not a complete listing.
Chinese character dictionaries often allow users to locate entries in several different ways. Many Chinese, Japanese, and Korean dictionaries of Chinese characters list characters in radical order: characters are grouped together by radical, and radicals containing fewer strokes come before radicals containing more strokes. Under each radical, characters are listed by their total number of strokes. It is often also possible to search for characters by sound, using pinyin (in Chinese dictionaries), zhuyin (in Taiwanese dictionaries), kana (in Japanese dictionaries) or hangul (in Korean dictionaries). Most dictionaries also allow searches by total number of strokes, and individual dictionaries often allow other search methods as well.
For instance, to look up the character where the sound is not known, e.g., 松 (pine tree), the user first determines which part of the character is the radical (here 木), then counts the number of strokes in the radical (four), and turns to the radical index (usually located on the inside front or back cover of the dictionary). Under the number "4" for radical stroke count, the user locates 木, then turns to the page number listed, which is the start of the listing of all the characters containing this radical. This page will have a sub-index giving remainder stroke numbers (for the non-radical portions of characters) and page numbers. The right half of the character also contains four strokes, so the user locates the number 4, and turns to the page number given. From there, the user must scan the entries to locate the character he or she is seeking. Some dictionaries have a sub-index which lists every character containing each radical, and if the user knows the number of strokes in the non-radical portion of the character, he or she can locate the correct page directly.
Another dictionary system is the four corner method, where characters are classified according to the "shape" of each of the four corners.
Most modern Chinese dictionaries and Chinese dictionaries sold to English speakers use the traditional radical-based character index in a section at the front, while the main body of the dictionary arranges the main character entries alphabetically according to their pinyin spelling. To find a character with unknown sound using one of these dictionaries, the reader finds the radical and stroke number of the character, as before, and locates the character in the radical index. The character's entry will have the character's pronunciation in pinyin written down; the reader then turns to the main dictionary section and looks up the pinyin spelling alphabetically.
Mongolian text from The Secret History of the Mongols in Chinese transcription, with a glossary on the right of each row.Along with Persian and Arabic, Chinese characters were also used as a foreign script to write the Mongolian language, where characters were used to phonetically transcribe Mongolian sounds. Before the 13th century and the establishment of the Mongolian script, foreign scripts such as Chinese had to be used to write the Mongolian language. Most notably, the only surviving copies of The Secret History of the Mongols were written in such a manner; the Chinese characters 忙豁侖紐察 脫[卜]察安 (Pinyin: mánghuōlúnniǔchá tuō[bo]chá'ān) is the rendering of Mongγol-un niγuca tobčiyan, the title in Mongolian.
The oldest known record of the Sawndip characters used by the Zhuang, a non-Han peoples from what is today known as Guangxi, is from a stele dating from 689, which predates the earliest example of Vietnamese chữ Nôm.
The Chinese script spread to Korea together with Buddhism from the 7th century (Hanja). The Japanese Kanji were adopted for recording the Japanese language from the 8th century AD.
Comparing the Shuowen Jiezi and Hanyu Da Zidian reveals that the overall number of characters recorded in dictionaries has increased 577 percent over 1,900 years. Depending upon how one counts variants, 50,000+ is a good approximation for the current total number. This correlates with the most comprehensive Japanese and Korean dictionaries of Chinese characters; the Dai Kan-Wa jiten has some 50,000 entries, and the Han-Han Dae Sajeon has over 57,000. The latest behemoth, the Zhonghua Zihai, records a staggering 85,568 single characters, although even this fails to list all characters known, ignoring the roughly 1,500 Japanese-made kokuji given in the Kokuji no Jiten[52] as well as the Chu Nom inventory only used in Vietnam in past days.
Modified radicals and obsolete variants are two common reasons for the ever-increasing number of characters. There are about 300 radicals and 100 are in common use. Creating a new character by modifying the radical is an easy way to disambiguate homographs among xíngshēngzì pictophonetic compounds. This practice began long before the standardization of Chinese script by Qin Shi Huang and continues to the present day. The traditional 3rd-person pronoun tā (他 "he; she; it"), which is written with the "person radical", illustrates modifying significs to form new characters. In modern usage, there is a graphic distinction between tā (她 "she") with the "woman radical", tā (牠 "it") with the "animal radical", tā (它 "it") with the "roof radical", and tā (祂 "He") with the "deity radical", One consequence of modifying radicals is the fossilization of rare and obscure variant logographs, some of which are not even used in Classical Chinese. For instance, he 和 "harmony; peace", which combines the "grain radical" with the "mouth radical", has infrequent variants 咊 with the radicals reversed and 龢 with the "flute radical".
In the People's Republic of China, which uses Simplified Chinese characters, the Xiàndài Hànyǔ Chángyòng Zìbiǎo (现代汉语常用字表; Chart of Common Characters of Modern Chinese) lists 2,500 common characters and 1,000 less-than-common characters, while the Xiàndài Hànyǔ Tōngyòng Zìbiǎo (现代汉语通用字表; Chart of Generally Utilized Characters of Modern Chinese) lists 7,000 characters, including the 3,500 characters already listed above. GB2312, an early version of the national encoding standard used in the People's Republic of China, has 6,763 code points. GB18030, the modern, mandatory standard, has a much higher number. The Hànyǔ Shuǐpíng Kǎoshì proficiency test covers approximately 5,000 characters.
In the ROC, which uses Traditional Chinese characters, the Ministry of Education's Chángyòng Guózì Biāozhǔn Zìtǐ Biǎo (常用國字標準字體表; Chart of Standard Forms of Common National Characters) lists 4,808 characters; the Cì Chángyòng Guózì Biāozhǔn Zìtǐ Biǎo (次常用國字標準字體表; Chart of Standard Forms of Less-Than-Common National Characters) lists another 6,341 characters. The Chinese Standard Interchange Code (CNS11643)—the official national encoding standard—supports 48,027 characters, while the most widely used encoding scheme, BIG-5, supports only 13,053.
In Hong Kong, which uses Traditional Chinese characters, the Education and Manpower Bureau's Soengjung Zi Zijing Biu (常用字字形表), intended for use in elementary and junior secondary education, lists a total of 4,759 characters.
In addition, there is a large corpus of dialect characters, which are not used in formal written Chinese but represent colloquial terms in non-Mandarin Chinese spoken forms. One such variety is Written Cantonese, in widespread use in Hong Kong even for certain formal documents, due to the former British colonial administration's recognition of Cantonese for use for official purposes. In Taiwan, there is also an informal body of characters used to represent the spoken Hokkien (Min Nan) dialect. Many dialects have specific characters for words exclusive to the dialect, for example, the vernacular character
, pronounced cii11 in Hakka, means "to kill"[53]. Furthermore, Shanghainese Chinese also has its own series of written text, but these are not widely used in actual texts, Mandarin being the preference for all mainland regions. (For instance, 㑚, 哎垯, and 呒没, all of which are widely known and used by Shanghainese.)
The one area where character usage is officially restricted is in names, which may contain only government-approved characters. Since the Jōyō kanji list excludes many characters which have been used in personal and place names for generations, an additional list, referred to as the Jinmeiyō kanji (人名用漢字 lit. "kanji for use in personal names"), is published. It currently contains 983 characters, bringing the total number of government-endorsed characters to 2928. (See also the Names section of the kanji article.)
Today, a well-educated Japanese person may know upwards of 3,500 kanji.[citation needed] The kanji kentei (日本漢字能力検定試験 Nihon Kanji Nōryoku Kentei Shiken or Test of Japanese Kanji Aptitude) tests a speaker's ability to read and write kanji. The highest level of the kanji kentei tests on 6,000 kanji, though in practice few people attain (or need to attain) this level.
Written Japanese also includes a pair of syllabic scripts known as kana, which are used in combination with kanji. Not all words in modern Japanese can be expressed with kanji alone, requiring the use of kana in written communication.
In Korea, 한자 hanja have become a politically contentious issue, with some Koreans urging a "purification" of the national language and culture by totally abandoning their use. These individuals encourage the exclusive use of the native hangul alphabet throughout Korean society and the end to character education in public schools.
In South Korea, educational policy on characters has swung back and forth, often swayed by education ministers' personal opinions. At times, middle and high school students have been formally exposed to 1,800 to 2,000 basic characters, albeit with the principal focus on recognition, with the aim of achieving newspaper-literacy. Since there is little need to use hanja in everyday life, young adult Koreans are often unable to read more than a few hundred characters.
There is a clear trend toward the exclusive use of hangul in day-to-day South Korean society. Hanja are still used to some extent, particularly in newspapers, weddings, place names and calligraphy. Hanja is also extensively used in situations where ambiguity must be avoided, such as academic papers, high-level corporate reports, government documents, and newspapers; this is due to the large number of homonyms that have resulted from extensive borrowing of Chinese words.
The issue of ambiguity is the main hurdle in any effort to "cleanse" the Korean language of Chinese characters. Characters convey meaning visually, while alphabets convey guidance to pronunciation, which in turn hints at meaning. As an example, in Korean dictionaries, the phonetic entry for 기사 gisa yields more than 30 different entries. In the past, this ambiguity had been efficiently resolved by parenthetically displaying the associated hanja.
In the modern hangul-based Korean writing system, Chinese characters are no longer used to represent native morphemes.
In North Korea, the government, wielding much tighter control than its sister government to the south, has banned Chinese characters from virtually all public displays and media, and mandated the use of hangul in their place.
the 3 names of Chinese character in Vietnamese: chữ Hán, chữ Nho, Hán tự.Although now nearly extinct in Vietnam, varying scripts of Chinese characters (hán tự) were once in widespread use to write the language, although hán tự became limited to ceremonial uses beginning in the 19th century. Similarly to Japan and Korea, Chinese (especially Literary Chinese) was used by the ruling classes, and the characters were eventually adapted to write Vietnamese. To express native Vietnamese words which had different pronunciations from the Chinese, Vietnamese developed the Chữ Nôm script which used various methods to distinguish native Vietnamese words from Chinese. Vietnamese is currently exclusively written in the Vietnamese alphabet, a derivative of the Latin alphabet.
One man who has encountered this problem is Taiwanese politician Yu Shyi-kun (游錫堃, pinyin Yóu Xíkūn), due to the rarity of the last character in his name. Newspapers have dealt with this problem in varying ways, including using software to combine two existing, similar characters, including a picture of the personality, or, especially as is the case with Yu Shyi-kun, simply substituting a homophone for the rare character in the hope that the reader would be able to make the correct inference. Taiwanese political posters, movie posters etc. will often add the bopomofo phonetic symbols next to such a character. Japanese newspapers may render such names and words in katakana instead of kanji, and it is accepted practice for people to write names for which they are unsure of the correct kanji in katakana instead.
There are also some extremely complex characters which have understandably become rather rare. According to Joël Bellassen (1989), the most complex Chinese character is
/𪚥 (U+2A6A5) zhé 
listen (help·info) (pictured below, left), meaning "verbose" and boasting sixty-four strokes; this character fell from use around the 5th century. It might be argued, however, that while boasting the most strokes, it is not necessarily the most complex character (in terms of difficulty), as it simply requires writing the same sixteen-stroke character 龍 lóng (lit. "dragon") four times in the space for one. Another 64-stroke character is 
/𠔻 (U+2053B) zhèng composed of 興 xīng/xìng (lit. "flourish") four times.
One of the most complex characters found in modern Chinese dictionaries[54] is 齉 (U+9F49) nàng listen (help·info) (pictured below, middle image), meaning "snuffle" (that is, a pronunciation marred by a blocked nose), with "just" thirty-six strokes. However, this is not in common use. The most complex character that can be input using the Microsoft New Phonetic IME 2002a for Traditional Chinese is 龘 tà "the appearance of a dragon walking"; it is composed of the dragon radical represented three times, for a total of 16 × 3 = 48 strokes. Among the most complex characters in modern dictionaries and also in frequent modern use are 籲 yù "to implore", with 32 strokes; 鬱 yù: "luxuriant, lush; gloomy", with 29 strokes, as in 憂鬱 yōuyù "depressed", with 15 and 29 strokes, respectively; 豔 yàn "colorful", with 28 strokes; and 釁 xìn "quarrel", with 25 strokes, as in 挑釁 tiǎoxìn "to pick a fight". Also in occasional modern use is 鱻 xiān “fresh” (variant of 鮮 xiān) with 33 strokes.
In Japanese, an 84-stroke kokuji exists[55]—it is composed of three "cloud" (雲) characters on top of the abovementioned triple "dragon" character (龘). Also meaning "the appearance of a dragon in flight", it has been pronounced おとど otodo, たいと taito, and だいと daito.
The most complex Chinese character still in use may be biáng (pictured right, bottom), with 57 strokes, which refers to Biang biang noodles, a type of noodle from China's Shaanxi province. This character along with syllable biang cannot be found in dictionaries. The fact that it represents a syllable that does not exist in any Standard Mandarin word means that it could be classified as a dialectal character.
Chinese calligraphy of mixed styles written by Song Dynasty (1051–1108 AD) poet Mifu. For centuries, the Chinese literati were expected to master the art of calligraphy.The art of writing Chinese characters is called Chinese calligraphy. It is usually done with ink brushes. In ancient China, Chinese calligraphy is one of the Four Arts of the Chinese Scholars. There is a minimalist set of rules of Chinese calligraphy. Every character from the Chinese scripts is built into a uniform shape by means of assigning it a geometric area in which the character must occur. Each character has a set number of brushstrokes; none must be added or taken away from the character to enhance it visually, lest the meaning be lost. Finally, strict regularity is not required, meaning the strokes may be accentuated for dramatic effect of individual style. Calligraphy was the means by which scholars could mark their thoughts and teachings for immortality, and as such, represent some of the more precious treasures that can be found from ancient China.
The number of Chinese characters contained in the Kangxi dictionary is approximately 47,035, although a large number of these are rarely used variants accumulated throughout history. Studies carried out in China have shown that full literacy in the Chinese language requires a knowledge of only between three and four thousand characters.[4]
In the Chinese writing system, the characters are monosyllabic, each usually corresponding to a spoken syllable with a basic meaning. However, although Chinese words may be formed by characters with basic meanings, a majority of words in Mandarin Chinese require two or more characters to write (thus are polysyllabic) but have meaning that is distinct from but dependent on the characters they are made from.[5] Cognates in the various Chinese languages/dialects which have the same or similar meaning but different pronunciations can be written with the same character.
Chinese characters have also been used and in some cases continue to be used in other languages, most significantly Japanese (where a single character can represent several spoken syllables), Korean, and Vietnamese. Chinese characters are used both by meaning to represent native words, ignoring the Chinese pronunciation, and by meaning and sound, to represent Chinese loanwords. These foreign pronunciations of Chinese characters are known as Sinoxenic pronunciations, and have been useful in the reconstruction of Ancient Chinese.
[edit] History
[edit] Precursors
Main article: Neolithic signs in China
In the last 50 or so years, inscriptions have been found on pottery in a variety of locations in China such as Bànpō near Xī'ān, as well as on bone and bone marrows at Hualouzi, Chang'an County near Xi'an. These simple, often geometric marks have been frequently compared to some of the earliest known Chinese characters, on the oracle bones, and some have taken them to mean that the history of Chinese writing extends back over six millennia.However, because these marks occur singly, without any context to imply, and because they are generally extremely crude and simple, Qiú Xīguī (2000, p. 31) concluded that "we do not have any basis for stating that these constituted writing, nor is there reason to conclude that they were ancestral to Shang dynasty Chinese characters." Isolated graphs and pictures continue to be found periodically, frequently accompanied by media reports pushing back the purported beginnings of Chinese writing a few thousand years. For example, at Damaidi in Ningxia, 3,172 pictorial cliff carvings dating to 6000–5000 BC have been discovered, leading to headlines such as "Chinese writing '8,000 years old.'"[6] Similarly, archaeologists report finding a few inscribed symbols on tortoise shells at the Neolithic site of Jiahu in Henan, dated to around 6,600–6,200 BCE, leading to headlines of "'Earliest writing' found in China.[7]
In his comment released to the BBC, Professor David Keightley urged caution in the latter instance, pointing to the lack of any direct cultural connection to Shāng culture, combined with gaps between them of many millennia. However, in the same BBC article, a supporting argument is provided by Dr Garman Harbottle, of the Brookhaven National Laboratory in New York, US, who collaborated with a team of archaeologists at the University of Science and Technology of China, in Anhui province in the discovery. Dr Harbottle points to the persistence of sign use at different sites along the Yellow River throughout the Neolithic and up to the Shāng period, when a complex writing system appears.[7]
One group of sites of interest is the Dàwènkǒu culture sites (2800–2500 BCE, only one millennium earlier than the early Shāng culture sites, and positioned so as to be plausibly albeit indirectly ancestral to the Shāng). There, a few inscribed pottery and jade pieces have been found,[8] one of which combines pictorial elements (resembling, according to some, a sun, moon or clouds, and fire or a mountain) in a stack which brings to mind the compounding of elements in Chinese characters. Major scholars are divided in their interpretation of such inscribed symbols. Some, such as Yú Xǐngwú,[9] Táng Lán[10] and Lǐ Xuéqín,[11] have identified these with specific Chinese characters. Others such as Wang Ningsheng[12] interpret them as pictorial symbols such as clan insignia, rather than writing. But in the view of Wang Ningsheng, "True writing begins when it represents sounds and consists of symbols that are able to record language. The few isolated figures found on pottery still cannot substantiate this point."[13]
[edit] Legendary origins
According to legend, Chinese characters were invented by Cangjie (c. 2650 BC), a bureaucrat under the legendary emperor, Huangdi. The legend tells that Cangjie was hunting on Mount Yangxu (today Shanxi) when he saw a tortoise whose veins caught his curiosity. Inspired by the possibility of a logical relation of those veins, he studied the animals of the world, the landscape of the earth, and the stars in the sky, and invented a symbolic system called zì—Chinese characters. It was said that on the day the characters were born, Chinese heard the devil mourning, and saw crops falling like rain, as it marked the beginning of the world.[edit] Oracle bone script
Main article: Oracle bone script
Shāng Dynasty Oracle Bone Script on Ox Scapula, Linden-Museum, Stuttgart, Germany. Photo by Dr. Meierhofer
[edit] Bronze Age: Parallel script forms and gradual evolution
Main article: Chinese bronze inscriptions
The traditional picture of an orderly series of scripts, each one invented suddenly and then completely displacing the previous one as implied by neat series of graphs in popular books on the subject, has been conclusively demonstrated to be fiction by the archaeological finds and scholarly research of the last half century.[17] Gradual evolution and the coexistence of two or more scripts was more often the case. As early as the Shāng dynasty, oracle bone script coexisted as a simplified form alongside the normal script of bamboo books (preserved for us in typical bronze inscriptions) as well as extra-elaborate pictorial forms (often clan emblems) found on many bronzes.
[edit] Unification: Seal script, vulgar writing and proto-clerical
Seal script, which had evolved slowly in the state of Qín during the Eastern Zhōu dynasty, became standardized and adopted as the formal script for all of China in the Qín dynasty (leading to a popular misconception that it was invented at that time), and was still widely used for decorative engraving and seals (name chops, or signets) in the Hàn dynasty onward. But despite the Qín script standardization, more than one script remained in use at the time. For example, a little-known, rectilinear and roughly executed kind of common (vulgar) writing had for centuries coexisted with the more formal seal script in the Qín state, and the popularity of this vulgar writing grew as the use of writing itself became more widespread.[20] By the Warring States period, an immature form of clerical script called “early clerical” or “proto-clerical” had already developed in the state of Qín[21] based upon thus vulgar writing, and with influence from seal script as well.[22] The coexistence of the three scripts, small seal, vulgar and proto-clerical, with the latter evolving gradually in the Qín to early Hàn dynasties into clerical script, runs counter to the traditional beliefs that the Qín dynasty had one script only, and that clerical script was suddenly invented in the early Hàn dynasty from the small seal script.[edit] Hàn Dynasty
[edit] Proto-clerical evolving to clerical
Proto-clerical, which had emerged by the Warring States period from vulgar Qín writing, matured gradually, and by the early Western Hàn, was little different from that of the Qín.[23] Recently discovered bamboo slips show the script becoming mature clerical script by the middle to late reign of Emperor Wǔ of the W. Hàn,[24] who ruled 141 BCE to 87 BCE.[edit] Clerical & clerical cursive
Contrary to popular belief of one script per period, there were in fact multiple scripts in use during the Hàn.[25] Although mature clerical script, also called 八分 bāfēn[26] script, was dominant at that time, an early type of cursive script was also in use in the Hàn by at least as early as 24 BCE (very late W. Hàn),[27] incorporating cursory (sic) forms popular at that period as well as many[28] from the vulgar writing of the Warring State of Qín. By around the Eastern Jìn dynasty this Hàn cursive became known as 章草 zhāngcǎo (also known as 隶草 / 隸草 lìcǎo today), or in English sometimes clerical cursive, ancient cursive, or draft cursive. Some believe that the name, based on 章 zhāng meaning "orderly", is because this was a more orderly form[29] of cursive than the modern form of cursive emerging around the E. Jìn and still in use today, called 今草 jīncǎo or "modern cursive".[30][edit] Neo-clerical
Around the mid Eastern Hàn,[29] a simplified and easier to write form of clerical appeared, which Qiú (2000, p. 113 & 139) terms "neo-clerical" (新隶体 / 新隸體 xīnlìtǐ) and by the late E. Hàn it had become the dominant daily script,[29] although the formal, mature bāfēn (八分) clerical script remained in use for formal situations such as engraved stelae.[29] Some have described this neo-clerical script as a transition between clerical and regular script,[29] and it remained in use through the Cáo Wèi and Jìn dynasties.[31][edit] Semi-cursive
By the late E. Hàn, an early form of semi-cursive script appeared,[32] developing out of a somewhat cursively written kind of neo-clerical script[33] and cursive.[34] It was traditionally attributed to Liú Déshēng ca. 147–188 CE,[31][35] although such attributions refer to early masters of a script rather than to their actual inventors, since the scripts generally evolved into being over time. Qiú 2000, p. 140 gives examples of early semi-cursive showing that it had popular origins rather than being only Liú’s invention.[edit] Written styles
The Shang dynasty Oracle Bone and Zhou dynasty scripts found on Chinese bronze inscriptions being no longer used, the oldest script that is still in use today is the Seal Script (篆书 / 篆書 zhuànshū). It evolved organically out of the Spring and Autumn period Zhou script, and was adopted in a standardized form under the first Emperor of China, Qin Shi Huang. The seal script, as the name suggests, is now only used in artistic seals. Few people are still able to read it effortlessly today, although the art of carving a traditional seal in the script remains alive; some calligraphers also work in this style.
Scripts that are still used regularly are the "Clerical Script" (隶书 / 隸書 lìshū) of the Qin Dynasty to the Han Dynasty, the Weibei (Chinese: 魏碑; pinyin: wèibēi), the "Regular Script" (楷书 / 楷書 kǎishū) used mostly for printing, and the "Semi-cursive Script" (行书 / 行書 xíngshū) used mostly for handwriting.
The Cursive Script (草书 / 草書 cǎoshū, literally "grass script") is not in general use, and is a purely artistic calligraphic style. The basic character shapes are suggested, rather than explicitly realized, and the abbreviations are extreme. Despite being cursive to the point where individual strokes are no longer differentiable and the characters often illegible to the untrained eye, this script (also known as draft) is highly revered for the beauty and freedom that it embodies. Some of the Simplified Chinese characters adopted by the People's Republic of China, and some of the simplified characters used in Japan, are derived from the Cursive Script. The Japanese hiragana script is also derived from this script.
There also exist scripts created outside China, such as the Japanese Edomoji styles; these have tended to remain restricted to their countries of origin, rather than spreading to other countries like the scripts described above.
[edit] Wèi to Jìn period
[edit] Regular script
Regular script has been attributed to Zhōng Yáo, of the E. Hàn to Cáo Wèi period (ca 151–230 CE), who has been called the “father of regular script”. However, some scholars[36] think that one person alone cannot develop a new script which is universally adopted, but only be a contributor to its gradual formation. The earliest surviving pieces written in regular script are copies of his works, including at least one copied by Wáng Xīzhī. This new script, which is the dominant modern Chinese script, developed out of a neatly written form of early semi-cursive, with addition of the pause (顿 / 頓 dùn) technique to end horizontal strokes, plus heavy tails on strokes which are written to downward right diagonal.[37] Thus, early regular script emerged from a neat, formal form of semi-cursive which had emerged from neo-clerical (a simplified, convenient form of clerical). It then matured further in the Eastern Jìn dynasty in the hands of the "Sage of Calligraphy" Wáng Xīzhī and his son Wáng Xiànzhī. It was not, however, in widespread use at that time, and most continued using neo-clerical or a somewhat semi-cursive form of it for daily writing,[37] while the conservative bāfēn clerical script remained in use on some stelae, alongside some semi-cursive, but primarily neo-clerical.[38][edit] Modern cursive
Meanwhile, modern cursive script slowly emerged out of the clerical cursive (zhāngcǎo) script during the Cáo Wèi to Jìn period, under the influence of both semi-cursive and the newly emerged regular script.[39] Cursive was formalized in the hands of a few master calligraphers, the most famous and influential of which was Wáng Xīzhī.[40] However, because modern cursive is so cursive, it is hard to read, and never gained widespread use outside of literati circles.[edit] Dominance and maturation of regular script
It was not until the Southern and Northern Dynasties that regular script rose to dominant status.[41] During that period, regular script continued evolving stylistically, reaching full maturity in the early Táng dynasty. Some call the writing of the early Táng calligrapher Ōuyáng Xún (557–641) the first mature regular script. After this point, although developments in the art of calligraphy and in character simplification still lay ahead, there were no more major stages of evolution for the mainstream script.[edit] Modern history
Although most of the simplified Chinese characters in use today are the result of the works moderated by the government of the People's Republic of China (PRC) in the 1950s and 60s, character simplification predates the PRC's formation in 1949. One of the earliest proponents of character simplification was Lu Feikui, who proposed in 1909 that simplified characters should be used in education. In the years following the May Fourth Movement in 1919, many anti-imperialist Chinese intellectuals sought ways to modernise China. In the 1930s and 1940s, discussions on character simplification took place within the Kuomintang government, and a large number of Chinese intellectuals and writers have long maintained that character simplification would help boost literacy in China. In many world languages, literacy has been promoted as a justification for spelling reforms. The People's Republic of China issued its first round of official character simplifications in two documents, the first in 1956 and the second in 1964. In the 1950s and 1960s, while confusion about simplified characters was still rampant, transitional characters that mixed simplified parts with yet-to-be simplified parts of characters together appeared briefly, then disappeared."Han unification" was completed for the purposes of Unicode in 1991 (Unicode 1.0).
[edit] Formation of characters
Main articles: Chinese character classification and radical (Chinese character)
The presumed methods of forming characters were first classified c. 100 AD by the Chinese linguist Xu Shen, whose etymological dictionary Shuowen Jiezi (说文解字 / 說文解字) divides the script into six categories, the liùshū (六书 / 六書). While the categories and classification are occasionally problematic and arguably fail to reflect the complete nature of the Chinese writing system, this account has been perpetuated by its long history and pervasive use.[42]
Four percent of Chinese characters are derived directly from individual pictograms, though in most cases the resemblance to an object is no longer clear. Others are ideograms, compound ideograms, where two ideograms are combined to give a third reading, or rebus. But most characters are phono-semantic compounds, with one element to indicate the general category of meaning and the other to suggest the pronunciation. Again, in many cases the suggested sound is no longer accurate.
[edit] Pictograms
- 象形字 xiàngxíngzì
There is no concrete number for the proportion of modern characters that are pictographic in nature; however, Xu Shen (c. 100 AD) estimated that 4% of characters fell into this category.
[edit] Ideograms
- 指事字 zhǐshìzì
[edit] Ideogrammic compounds
- 会意字 / 會意字 huìyìzì
Xu Shen estimated that 13% of characters fall into this category.
Some scholars flatly reject the existence of this category, opining that failure of modern attempts to identify a phonetic in a compound is due simply to our not looking at ancient "secondary readings", which were lost over time.[45] For example, the character 安 ān "peace", a combination of "roof" 宀 and "woman" 女, is commonly cited as an ideogrammic compound, purportedly motivated by a meaning such as "all is peaceful with the woman at home". However, there is evidence that 女 was once a polyphone with a secondary reading of *an, as may be gleaned from the set 妟 yàn "tranquil", 奻 nuán "to quarrel", and 姦 jiān "licentious". Supporting this reasoning is the fact that modern interpretations often neglect archaic forms that were in use when the characters were created.
These arguments notwithstanding, there are some characters that do appear to genuinely belong to this category. It is doubtful that secondary readings can be found for many cases, and the characters 林, 森, 明, 休, and 好 are all attested in oracle bone script, with the same components as the modern forms.
[edit] Phono-semantic compounds
- 形声字 / 形聲字 xíngshēngzì
Examples are 河 hé "river", 湖 hú "lake", 流 liú "stream", 沖 chōng "riptide" (or "flush"), 滑 huá "slippery". All these characters have on the left a radical of three short strokes, which is a simplified pictograph for a river, indicating that the character has a semantic connection with water; the right-hand side in each case is a phonetic indicator. For example, in the case of 沖 chōng (Old Chinese /druŋ/[46]), the phonetic indicator is 中 zhōng (Old Chinese /truŋ/[47]), which by itself means "middle". In this case it can be seen that the pronunciation of the character is slightly different from that of its phonetic indicator; this process means that the composition of such characters can sometimes seem arbitrary today. Further, the choice of radicals may also seem arbitrary in some cases; for example, the radical of 貓 māo "cat" is 豸 zhì, originally a pictograph for worms,[citation needed] but in characters of this sort indicating an animal of any sort.
Xu Shen (c. 100 CE) placed approximately 82% of characters into this category, while in the Kangxi Dictionary (1716 CE) the number is closer to 90%, due to the extremely productive use of this technique to extend the Chinese vocabulary.
This method is still sometimes used to form new characters, for example 钚 bù "plutonium") is the metal radical 金 jīn plus the phonetic component 不 bù, described in Chinese as "不 gives sound, 金 gives meaning". Many Chinese names of elements in the periodic table and many other chemistry-related characters were formed this way.
[edit] Transformed cognates
- 转注字 / 轉注字 zhuǎnzhùzì
[edit] Rebus
- 假借字 jiǎjièzì
[edit] Variants
Main article: Variant Chinese character
Just as Roman letters have a characteristic shape (lower-case letters mostly occupying the x-height, with ascenders or descenders on some letters), Chinese characters occupy a more or less square area in which the components of every character are written to fit in order to maintain a uniform size and shape, especially with small printed characters in Ming and sans-serif styles. Because of this, beginners often practise writing on squared graph paper, and the Chinese sometimes use the term "Square-Block Characters" (方块字 / 方塊字; fāngkuàizì), sometimes translated as tetragraph[citation needed], in reference to Chinese characters.Despite standardization, some nonstandard forms are commonly used, especially in handwriting.
[edit] Regional standards
The nature of Chinese characters makes it very easy to produce allographs for many characters, and there have been many efforts at orthographical standardization throughout history. In recent times, the widespread usage of the characters in several different nations has prevented any particular system becoming universally adopted and the standard form of many Chinese characters thus varies in different regions.Mainland China adopted simplified characters in 1956, but Traditional Chinese characters are still used in Hong Kong, Macau and Taiwan. Singapore has also adopted Simplified Chinese characters. Postwar Japan has used its own less drastically simplified characters, Shinjitai, since 1946, while South Korea has limited its use of Chinese characters, and Vietnam and North Korea have completely abolished their use in favour of romanized Vietnamese and Hangul, respectively.
The standard character forms of each region are described in:
- The List of Frequently Used Characters in Modern Chinese for Mainland China.
- The List of Forms of Frequently Used Characters for Hong Kong.
- The Standard Form of National Characters for Taiwan.
- The list of Jōyō kanji for Japan.
- The Kangxi Dictionary (de facto) for Korea.
[edit] Typography
Ming and sans-serif are the most popular in body text and are based on regular script for Chinese characters akin to Western serif and sans-serif typefaces, respectively. Regular script typefaces emulate regular script.
The Song typeface (宋体 / 宋體, sòngtǐ) is also known as Minchō (明朝) in Japan and Ming typeface (明体 / 明體, míngtǐ) in Taiwan and Hong Kong. The names of these styles come from the Song and Ming dynasties, when block printing flourished in China. Because the wood grain on printing blocks ran horizontally, it was fairly easy to carve horizontal lines with the grain. However, carving vertical or slanted patterns was difficult because those patterns intersect with the grain and break easily. This resulted in a typeface that has thin horizontal strokes and thick vertical strokes[citation needed]. To prevent wear and tear, the ending of horizontal strokes are also thickened[citation needed]. These design forces resulted in the current Ming typeface characterized by thick vertical strokes contrasted with thin horizontal strokes; triangular ornaments at the end of single horizontal strokes; and overall geometrical regularity.
Sans-serif typefaces, called black typeface (黑体 / 黑體, hēitǐ) in Chinese and Gothic typeface (ゴシック体) in Japanese, are characterized by simple lines of even thickness for each stroke, akin to sans-serif styles such as Arial and Helvetica in Western typography. This group of typefaces, first introduced on newspaper headlines[citation needed], is commonly used where legibility and neutrality is desired.
Regular script typefaces are also commonly used, but not as common as Ming or sans-serif typefaces for body text. Regular script typefaces are often used to teach students Chinese characters, and often aim to match the standard forms of the region where they are meant to be used. Most typefaces in the Song Dynasty were regular script typefaces which resembled a particular person's handwriting (e.g. the handwriting of Ouyang Xun, Yan Zhenqing, or Liu Gongquan), while most modern regular script typefaces tend toward anonymity and regularity.
[edit] Reform
Main articles: Simplified Chinese character and Japanese script reform
Chinese character simplification is the overall reduction of the number of strokes in the regular script of a set of Chinese characters.[edit] Simplification in China
The use of Traditional characters versus simplified characters varies greatly, and can depend on both the local customs and the medium. Before official reform, character simplifications were not officially sanctioned and generally adopted vulgar variants and idiosyncratic substitutions. Orthodox variants were mandatory in printed works, while the (unofficial) simplified characters would be used in everyday writing or quick notes. Since the 1950s, and especially with the publication of the 1964 list, the PRC has officially adopted Simplified Chinese characters for use in mainland China, while Hong Kong, Macau, and the ROC on Taiwan were not affected by the reform. There is no absolute rule for using either system, and often it is determined by what the target audience understands, as well as the upbringing of the writer.Although most often associated with the PRC, character simplification predates the 1949 communist victory. Caoshu, cursive written text, almost always includes character simplification, and simplified forms have always existed in print, albeit not for the most formal works. In the 1930s and 1940s, discussions on character simplification took place within the Kuomintang government, and a large number of Chinese intellectuals and writers have long maintained that character simplification would help boost literacy in China. Indeed, this desire by the Kuomintang to simplify the Chinese writing system (inherited and implemented by the CCP) also nursed aspirations of some for the adoption of a phonetic script, in imitation of the Roman alphabet, and spawned such inventions as the Gwoyeu Romatzyh.
The PRC issued its first round of official character simplifications in two documents, the first in 1956 and the second in 1964. A second round of character simplifications (known as erjian, or "second round simplified characters") was promulgated in 1977. It was poorly received, and in 1986 the authorities rescinded the second round completely, while making six revisions to the 1964 list, including the restoration of three traditional characters that had been simplified: 叠 dié, 覆 fù, 像 xiàng.
Many of the simplifications adopted had been in use in informal contexts for a long time, as more convenient alternatives to their more complex standard forms. For example, the orthodox character 來 lái ("come") was written with the structure 来 in the clerical script (隶书 / 隸書, lìshū) of the Han dynasty. This clerical form uses one less stroke, and was thus adopted as a simplified form. The character 雲 yún ("cloud") was written with the structure 云 in the oracle bone script of the Shāng dynasty, and had remained in use later as a phonetic loan in the meaning of "to say" while the the 雨 radical was added to differentiate meanings. The Simplified form adopts the original structure.
[edit] Japanese kanji
Main articles: Tōyō kanji and Shinjitai
In the years after World War II, the Japanese government also instituted a series of orthographic reforms. Some characters were given simplified forms called Shinjitai 新字体 (lit. "new character forms"; the older forms were then labelled the Kyūjitai 旧字体, lit. "old character forms"). The number of characters in common use was restricted, and formal lists of characters to be learned during each grade of school were established, first the 1850-character Tōyō kanji 当用漢字 list in 1945, and later the 1945-character Jōyō kanji 常用漢字 list in 1981. Many variant forms of characters and obscure alternatives for common characters were officially discouraged. This was done with the goal of facilitating learning for children and simplifying kanji use in literature and periodicals. These are simply guidelines, hence many characters outside these standards are still widely known and commonly used, especially those used for personal and place names (for the latter, see Jinmeiyō kanji).[edit] Southeast Asian Chinese communities
Singapore underwent three successive rounds of character simplification. These resulted in some simplifications that differed from those used in mainland China. It ultimately adopted the reforms of the PRC in their entirety as official, and has implemented them in the educational system. However, unlike in the PRC, personal names may still be registered in Traditional characters.Malaysia started teaching a set of simplified characters at schools in 1981, which were also completely identical to the Mainland China simplifications. Chinese newspapers in Malaysia are published in either set of characters, typically with the headlines in Traditional Chinese while the body is in Simplified Chinese.
Although in both countries the use of simplified characters is universal among the younger Chinese generation, a large majority of the older Chinese literate generation still use the traditional characters. Chinese shop signs are also generally written in traditional characters.
[edit] Comparisons of Traditional, Simplified, and Kanji
The following is a comparison of Chinese characters in the Standard Form of National Characters, a common Traditional Chinese standard used in Taiwan; the Xiàndài Hànyǔ Chángyòng Zìbiǎo, the standard for Mainland Chinese Simplified Chinese characters; and the Jōyō kanji, the standard for Japanese Kanji. "Simplified" refers to having significant differences from the Taiwan standard, not necessarily being a newly created character or a newly performed substitution. The characters in the Hong Kong standard and the Kangxi Dictionary are also known as "Traditional," but are not shown.| Traditional | Chinese simp. | Japanese Kanji | meaning | |
|---|---|---|---|---|
| Simplified in Mainland China, not Japan | 電 | 电 | 電 | electricity |
| 開 | 开 | 開 | open | |
| 東 | 东 | 東 | east | |
| 車 | 车 | 車 | car, vehicle | |
| 紅 | 红 | 紅 | red (crimson in Japanese) | |
| 無 | 无 | 無 | nothing | |
| 鳥 | 鸟 | 鳥 | bird | |
| 熱 | 热 | 熱 | hot | |
| 時 | 时 | 時 | time | |
| 語 | 语 | 語 | language | |
| Simplified in Japan, not Mainland China (In some cases this represents the adoption of different variants as standard) | 佛 | 佛 | 仏 | Buddha |
| 惠 | 惠 | 恵 | favour | |
| 德 | 德 | 徳 | moral, virtue | |
| 拜 | 拜 | 拝 | kowtow, pray to, worship | |
| 黑 | 黑 | 黒 | black | |
| 冰 | 冰 | 氷 | ice | |
| 兔 | 兔 | 兎 | rabbit | |
| 妒 | 妒 | 妬 | jealousy | |
| Simplified in Mainland China and Japan, but differently | 聽 | 听 | 聴 | listen |
| 證 | 证 | 証 | certificate, proof | |
| 龍 | 龙 | 竜 | dragon | |
| 龜 | 龟 | 亀 | turtle, tortoise | |
| 歲 | 岁 | 歳 | age, year | |
| 戰 | 战 | 戦 | fight, war | |
| 關 | 关 | 関 | bolt, relationship | |
| 鐵 | 铁 | 鉄 | iron, metal | |
| 圖 | 图 | 図 | picture, diagram | |
| 團 | 团 | 団 | group, regiment | |
| 轉 | 转 | 転 | turn | |
| 廣 | 广 | 広 | wide, broad | |
| 惡 | 恶 | 悪 | bad, evil | |
| 豐 | 丰 | 豊 | abundant | |
| 腦 | 脑 | 脳 | brain | |
| 雜 | 杂 | 雑 | miscellaneous | |
| 樂 | 乐 | 楽 | fun | |
| 氣 | 气 | 気 | air | |
| 廳 | 厅 | 庁 | hall, office | |
| Simplified in Mainland China and Japan in the same way | 學 | 学 | 学 | learn |
| 體 | 体 | 体 | body | |
| 點 | 点 | 点 | dot, point | |
| 貓 | 猫 | 猫 | cat | |
| 蟲 | 虫 | 虫 | insect | |
| 黃 | 黄 | 黄 | yellow | |
| 會 | 会 | 会 | meeting | |
| 萬 | 万 | 万 | ten-thousand | |
| 盜 | 盗 | 盗 | thief | |
| 寶 | 宝 | 宝 | treasure | |
| 國 | 国 | 国 | country | |
| 醫 | 医 | 医 | medicine |
[edit] Dictionaries
Dozens of indexing schemes have been created for arranging Chinese characters in Chinese dictionaries. The great majority of these schemes have appeared in only a single dictionary; only one such system has achieved truly widespread use. This is the system of radicals.Chinese character dictionaries often allow users to locate entries in several different ways. Many Chinese, Japanese, and Korean dictionaries of Chinese characters list characters in radical order: characters are grouped together by radical, and radicals containing fewer strokes come before radicals containing more strokes. Under each radical, characters are listed by their total number of strokes. It is often also possible to search for characters by sound, using pinyin (in Chinese dictionaries), zhuyin (in Taiwanese dictionaries), kana (in Japanese dictionaries) or hangul (in Korean dictionaries). Most dictionaries also allow searches by total number of strokes, and individual dictionaries often allow other search methods as well.
For instance, to look up the character where the sound is not known, e.g., 松 (pine tree), the user first determines which part of the character is the radical (here 木), then counts the number of strokes in the radical (four), and turns to the radical index (usually located on the inside front or back cover of the dictionary). Under the number "4" for radical stroke count, the user locates 木, then turns to the page number listed, which is the start of the listing of all the characters containing this radical. This page will have a sub-index giving remainder stroke numbers (for the non-radical portions of characters) and page numbers. The right half of the character also contains four strokes, so the user locates the number 4, and turns to the page number given. From there, the user must scan the entries to locate the character he or she is seeking. Some dictionaries have a sub-index which lists every character containing each radical, and if the user knows the number of strokes in the non-radical portion of the character, he or she can locate the correct page directly.
Another dictionary system is the four corner method, where characters are classified according to the "shape" of each of the four corners.
Most modern Chinese dictionaries and Chinese dictionaries sold to English speakers use the traditional radical-based character index in a section at the front, while the main body of the dictionary arranges the main character entries alphabetically according to their pinyin spelling. To find a character with unknown sound using one of these dictionaries, the reader finds the radical and stroke number of the character, as before, and locates the character in the radical index. The character's entry will have the character's pronunciation in pinyin written down; the reader then turns to the main dictionary section and looks up the pinyin spelling alphabetically.
[edit] Other languages
Besides Chinese/Sinitic languages, Japanese/Japonic languages, Korean, and Vietnamese language (Chữ nôm), a number of smaller Asian languages have been written or continue to be written using Han characters, with characters modified from Han characters, or using Han characters in combination with native characters. They include:- Bai language
- Dong language
- Iu Mien language
- Jurchen language, Jurchen script
- Khitan language, Khitan script
- Miao language
- Nakhi (Naxi) language (Geba script)
- Tangut language,[48][49] Tangut script
- Zhuang language (using Zhuang logograms, or "sawndip")
[edit] Historical spread
The Vietnamese Hán tự were first used in Vietnam during the millenium of Chinese rule starting in 111 BC, while adaptation for the vernacular Chữ Nôm script (based on Chinese characters) emerged around the 13th century AD.The oldest known record of the Sawndip characters used by the Zhuang, a non-Han peoples from what is today known as Guangxi, is from a stele dating from 689, which predates the earliest example of Vietnamese chữ Nôm.
The Chinese script spread to Korea together with Buddhism from the 7th century (Hanja). The Japanese Kanji were adopted for recording the Japanese language from the 8th century AD.
[edit] Number of Chinese characters
The total number of Chinese characters from past to present remains unknowable because new ones are developed all the time. Chinese characters are theoretically an open set. The number of entries in major Chinese dictionaries is the best means of estimating the historical growth of character inventory.| Year | Name of dictionary | Number of characters |
|---|---|---|
| 100 | Shuowen Jiezi | 9,353 |
| 543? | Yupian | 12,158 |
| 601 | Qieyun | 16,917 |
| 1011 | Guangyun | 26,194 |
| 1039 | Jiyun | 53,525 |
| 1615 | Zihui | 33,179 |
| 1716 | Kangxi Zidian | 47,035 |
| 1916 | Zhonghua Da Zidian | 48,000 |
| 1989 | Hanyu Da Zidian | 54,678 |
| 1994 | Zhonghua Zihai | 85,568 |
| 2004 | Yitizi Zidian | 106,230[51] |
| Year | Country | Name of dictionary | Number of characters |
|---|---|---|---|
| 2003 | Japan | Dai Kan-Wa jiten | 50,000+ |
| 2008 | South Korea | Han-Han Dae Sajeon | 53,667 |
Modified radicals and obsolete variants are two common reasons for the ever-increasing number of characters. There are about 300 radicals and 100 are in common use. Creating a new character by modifying the radical is an easy way to disambiguate homographs among xíngshēngzì pictophonetic compounds. This practice began long before the standardization of Chinese script by Qin Shi Huang and continues to the present day. The traditional 3rd-person pronoun tā (他 "he; she; it"), which is written with the "person radical", illustrates modifying significs to form new characters. In modern usage, there is a graphic distinction between tā (她 "she") with the "woman radical", tā (牠 "it") with the "animal radical", tā (它 "it") with the "roof radical", and tā (祂 "He") with the "deity radical", One consequence of modifying radicals is the fossilization of rare and obscure variant logographs, some of which are not even used in Classical Chinese. For instance, he 和 "harmony; peace", which combines the "grain radical" with the "mouth radical", has infrequent variants 咊 with the radicals reversed and 龢 with the "flute radical".
[edit] Chinese
It is usually said that about 2,000 characters are needed for basic literacy in Chinese (for example, to read a Chinese newspaper),[citation needed] and a well-educated person will know well in excess of 4,000 to 5,000 characters.[citation needed] Note that Chinese characters should not be confused with Chinese words, as the majority of modern Chinese words, unlike their Old Chinese and Middle Chinese counterparts, are multi-morphemic and multi-syllabic compounds, that is, most Chinese words are written with two or more characters; each character representing one syllable. Knowing the meanings of the individual characters of a word will often allow the general meaning of the word to be inferred, but this is not invariably the case.In the People's Republic of China, which uses Simplified Chinese characters, the Xiàndài Hànyǔ Chángyòng Zìbiǎo (现代汉语常用字表; Chart of Common Characters of Modern Chinese) lists 2,500 common characters and 1,000 less-than-common characters, while the Xiàndài Hànyǔ Tōngyòng Zìbiǎo (现代汉语通用字表; Chart of Generally Utilized Characters of Modern Chinese) lists 7,000 characters, including the 3,500 characters already listed above. GB2312, an early version of the national encoding standard used in the People's Republic of China, has 6,763 code points. GB18030, the modern, mandatory standard, has a much higher number. The Hànyǔ Shuǐpíng Kǎoshì proficiency test covers approximately 5,000 characters.
In the ROC, which uses Traditional Chinese characters, the Ministry of Education's Chángyòng Guózì Biāozhǔn Zìtǐ Biǎo (常用國字標準字體表; Chart of Standard Forms of Common National Characters) lists 4,808 characters; the Cì Chángyòng Guózì Biāozhǔn Zìtǐ Biǎo (次常用國字標準字體表; Chart of Standard Forms of Less-Than-Common National Characters) lists another 6,341 characters. The Chinese Standard Interchange Code (CNS11643)—the official national encoding standard—supports 48,027 characters, while the most widely used encoding scheme, BIG-5, supports only 13,053.
In Hong Kong, which uses Traditional Chinese characters, the Education and Manpower Bureau's Soengjung Zi Zijing Biu (常用字字形表), intended for use in elementary and junior secondary education, lists a total of 4,759 characters.
In addition, there is a large corpus of dialect characters, which are not used in formal written Chinese but represent colloquial terms in non-Mandarin Chinese spoken forms. One such variety is Written Cantonese, in widespread use in Hong Kong even for certain formal documents, due to the former British colonial administration's recognition of Cantonese for use for official purposes. In Taiwan, there is also an informal body of characters used to represent the spoken Hokkien (Min Nan) dialect. Many dialects have specific characters for words exclusive to the dialect, for example, the vernacular character
, pronounced cii11 in Hakka, means "to kill"[53]. Furthermore, Shanghainese Chinese also has its own series of written text, but these are not widely used in actual texts, Mandarin being the preference for all mainland regions. (For instance, 㑚, 哎垯, and 呒没, all of which are widely known and used by Shanghainese.)[edit] Japanese
Main article: Kanji
In Japanese there are 1,945 Jōyō kanji (常用漢字 lit. "frequently used kanji") designated by the Japanese Ministry of Education; these are taught during primary and secondary school. The list is a recommendation, not a restriction, and many characters missing from it are still in common use.The one area where character usage is officially restricted is in names, which may contain only government-approved characters. Since the Jōyō kanji list excludes many characters which have been used in personal and place names for generations, an additional list, referred to as the Jinmeiyō kanji (人名用漢字 lit. "kanji for use in personal names"), is published. It currently contains 983 characters, bringing the total number of government-endorsed characters to 2928. (See also the Names section of the kanji article.)
Today, a well-educated Japanese person may know upwards of 3,500 kanji.[citation needed] The kanji kentei (日本漢字能力検定試験 Nihon Kanji Nōryoku Kentei Shiken or Test of Japanese Kanji Aptitude) tests a speaker's ability to read and write kanji. The highest level of the kanji kentei tests on 6,000 kanji, though in practice few people attain (or need to attain) this level.
Written Japanese also includes a pair of syllabic scripts known as kana, which are used in combination with kanji. Not all words in modern Japanese can be expressed with kanji alone, requiring the use of kana in written communication.
[edit] Korean
Main article: Hanja
In times past, until the 15th century, in Korea, Literary Chinese was the dominant form of written communication, prior to the creation of hangul, the Korean alphabet. Much of the vocabulary, especially in the realms of science and sociology, comes directly from Chinese, comparable to Latin or Greek root words in European languages. However due to the lack of tones in Korean, as the words were imported from Chinese, many dissimilar characters took on identical sounds, and subsequently identical spelling in hangul. Chinese characters are sometimes used to this day for either clarification in a practical manner, or to give a distinguished appearance, as knowledge of Chinese characters is considered a high class attribute and an indispensable part of a classical education. It is also observed that the preference for Chinese characters is treated as being conservative and Confucian.In Korea, 한자 hanja have become a politically contentious issue, with some Koreans urging a "purification" of the national language and culture by totally abandoning their use. These individuals encourage the exclusive use of the native hangul alphabet throughout Korean society and the end to character education in public schools.
In South Korea, educational policy on characters has swung back and forth, often swayed by education ministers' personal opinions. At times, middle and high school students have been formally exposed to 1,800 to 2,000 basic characters, albeit with the principal focus on recognition, with the aim of achieving newspaper-literacy. Since there is little need to use hanja in everyday life, young adult Koreans are often unable to read more than a few hundred characters.
There is a clear trend toward the exclusive use of hangul in day-to-day South Korean society. Hanja are still used to some extent, particularly in newspapers, weddings, place names and calligraphy. Hanja is also extensively used in situations where ambiguity must be avoided, such as academic papers, high-level corporate reports, government documents, and newspapers; this is due to the large number of homonyms that have resulted from extensive borrowing of Chinese words.
The issue of ambiguity is the main hurdle in any effort to "cleanse" the Korean language of Chinese characters. Characters convey meaning visually, while alphabets convey guidance to pronunciation, which in turn hints at meaning. As an example, in Korean dictionaries, the phonetic entry for 기사 gisa yields more than 30 different entries. In the past, this ambiguity had been efficiently resolved by parenthetically displaying the associated hanja.
In the modern hangul-based Korean writing system, Chinese characters are no longer used to represent native morphemes.
In North Korea, the government, wielding much tighter control than its sister government to the south, has banned Chinese characters from virtually all public displays and media, and mandated the use of hangul in their place.
[edit] Vietnamese
[edit] Rare and complex characters
Often a character not commonly used (a "rare" or "variant" character) will appear in a personal or place name in Chinese, Japanese, Korean, and Vietnamese (see Chinese name, Japanese name, Korean name, and Vietnamese name, respectively). This has caused problems as many computer encoding systems include only the most common characters and exclude the less oft-used characters. This is especially a problem for personal names which often contain rare or classical, antiquated characters.One man who has encountered this problem is Taiwanese politician Yu Shyi-kun (游錫堃, pinyin Yóu Xíkūn), due to the rarity of the last character in his name. Newspapers have dealt with this problem in varying ways, including using software to combine two existing, similar characters, including a picture of the personality, or, especially as is the case with Yu Shyi-kun, simply substituting a homophone for the rare character in the hope that the reader would be able to make the correct inference. Taiwanese political posters, movie posters etc. will often add the bopomofo phonetic symbols next to such a character. Japanese newspapers may render such names and words in katakana instead of kanji, and it is accepted practice for people to write names for which they are unsure of the correct kanji in katakana instead.
There are also some extremely complex characters which have understandably become rather rare. According to Joël Bellassen (1989), the most complex Chinese character is
/𪚥 (U+2A6A5) zhé listen (help·info) (pictured below, left), meaning "verbose" and boasting sixty-four strokes; this character fell from use around the 5th century. It might be argued, however, that while boasting the most strokes, it is not necessarily the most complex character (in terms of difficulty), as it simply requires writing the same sixteen-stroke character 龍 lóng (lit. "dragon") four times in the space for one. Another 64-stroke character is 
/𠔻 (U+2053B) zhèng composed of 興 xīng/xìng (lit. "flourish") four times.One of the most complex characters found in modern Chinese dictionaries[54] is 齉 (U+9F49) nàng
listen (help·info) (pictured below, middle image), meaning "snuffle" (that is, a pronunciation marred by a blocked nose), with "just" thirty-six strokes. However, this is not in common use. The most complex character that can be input using the Microsoft New Phonetic IME 2002a for Traditional Chinese is 龘 tà "the appearance of a dragon walking"; it is composed of the dragon radical represented three times, for a total of 16 × 3 = 48 strokes. Among the most complex characters in modern dictionaries and also in frequent modern use are 籲 yù "to implore", with 32 strokes; 鬱 yù: "luxuriant, lush; gloomy", with 29 strokes, as in 憂鬱 yōuyù "depressed", with 15 and 29 strokes, respectively; 豔 yàn "colorful", with 28 strokes; and 釁 xìn "quarrel", with 25 strokes, as in 挑釁 tiǎoxìn "to pick a fight". Also in occasional modern use is 鱻 xiān “fresh” (variant of 鮮 xiān) with 33 strokes.In Japanese, an 84-stroke kokuji exists[55]—it is composed of three "cloud" (雲) characters on top of the abovementioned triple "dragon" character (龘). Also meaning "the appearance of a dragon in flight", it has been pronounced おとど otodo, たいと taito, and だいと daito.
The most complex Chinese character still in use may be biáng (pictured right, bottom), with 57 strokes, which refers to Biang biang noodles, a type of noodle from China's Shaanxi province. This character along with syllable biang cannot be found in dictionaries. The fact that it represents a syllable that does not exist in any Standard Mandarin word means that it could be classified as a dialectal character.
| Zhé, "verbose" | Zhèng (unknown meaning) |  Nàng, "poor enunciation due to snuffle" |  Taito, "the appearance of a dragon in flight" |
[edit] Chinese calligraphy
Main article: Chinese calligraphy
[edit] See also
- Variant Chinese character
- Stroke order
- Chinese Written Language
- Chinese language
- Simplified Chinese
- Traditional Chinese
- List of languages written in Chinese characters and derivatives of Chinese characters
- Romanization of Chinese
- Transcription into Chinese characters
- Wiktionary:Chinese total strokes index
- Wiktionary:Chinese radical index
- Eight Principles of Yong
- Chinese character encoding
- Chinese input methods for computers
- Han unification
- Chinese numerals, or how to write numbers with Chinese characters
- Blissymbols (an international auxiliary logographic script)
- Horizontal and vertical writing in East Asian scripts
- East Asian calligraphy
- Sinoxenic
- Sinosphere
- Kanji
- Hanja
[edit] References
- ^ "Chinese Writing Symbols". Kwintessential. http://www.kwintessential.co.uk/articles/article/China/Chinese-Writing-Symbols/1651. Retrieved 2010-03-20.
- ^ "History of Chinese Writing Shown in the Museums". CCTV online. http://en.artintern.net/index.php/news/main/html/1/1101. Retrieved 2010-03-20.
- ^ Jane P. Gardner & J. Elizabeth Mills. "Journey to East Asia". Everything.com, F+W Media. http://www.everything.com/journey-east-asia/. Retrieved 2010-03-20.
- ^ Norman, Jerry (2008). "Chinese Writing". http://www.asiasociety.org/education-learning/world-languages/chinese-language-initiatives/chinese-writing. Retrieved 2009-08-17.
- ^ East Asian Languages at pinyin.info
- ^ BBC NEWS | Asia-Pacific | Chinese writing '8,000 years old' ; "Carvings may rewrite history of Chinese characters". Xinhua online. 2007-05-18. http://news.xinhuanet.com/english/2007-05/18/content_6121225.htm. Retrieved 2007-05-19.; Unknown (2003-05-18). "'Chinese writing 8,000 years old'". BBC News. http://news.bbc.co.uk/2/hi/asia-pacific/6669569.stm. Retrieved 2007-11-17.
- ^ a b Paul Rincon (2003-04-17). "Earliest writing' found in China". BBC News. http://news.bbc.co.uk/2/hi/science/nature/2956925.stm.
- ^ Qiú 2000, p.38.
- ^ 于省吾 Yú Xǐngwú 1973, p.32; cited in Qiú 2000, p.35.
- ^ 唐蘭 Táng Lán 1975, p.72–73; cited in Qiú 2000, p.35.
- ^ Lǐ Xuéqín 李學勤 1985; cited in Qiú 2000, p.35.
- ^ Wang Ningsheng 1981, p.27; cited in Qiú 2000, p.35.
- ^ Wang, Ningsheng 1981, p.28; cited in Qiú 2000, p.38.
- ^ William G. Boltz: "Early Chinese Writing", World Archaeology, Vol. 17, No. 3, Early Writing Systems (1986), pp. 420–436 (436): The earliest known form of Chinese writing are the so-called 'oracle bone inscriptions' of the late Shang, divinatory inscriptions incised on turtle plastrons and ox scapulae, dating from about 1200-1050 B.C. Shang bronze inscriptions from about 1100 B.C. constitute the second carliest source of evidence for archaic Chinese writing.
- ^ David N. Keightley: "Art, Ancestors, and the Origins of Writing in China", Representations, No. 56, Special Issue: The New Erudition (1996), pp.68–95 (68): The oracle-bone inscriptions of the Late Shang dynasty (c. 1200-1050 B.C.), the earliest body of writing we yet possess for East Asia, were written in a script ancestral to all subsequent forms of Chinese writing.
- ^ John DeFrancis: Visible Speech. The Diverse Oneness of Writing Systems: Chinese
- ^ Qiú 2000 pp.63–4, 66, 86, 88–9, 104–7 & 124.
- ^ Qiú 2000, p.60, and pp.59–150 in general.
- ^ Chén Zhāoróng 2003.
- ^ Qiú 2000, p.104.
- ^ Qiú 2000; p.59 & p.104–7.
- ^ Qiú 2000, p.119.
- ^ Qiú 2000, p.l23.
- ^ Qiú 2000, p.119 & 123–4.
- ^ Qiú 2000, p.130.
- ^ Qiú 2000, p.121.
- ^ Qiú 2000, p.132–3 provides archaeological evidence for this dating, in contrast to unsubstantiated claims dating the beginning of cursive anywhere from the Qín to the Eastern Hàn.
- ^ Qiú 2000, p.131 &133.
- ^ a b c d e Qiú 2000, p.138.
- ^ Qiú 2000, p.131.
- ^ a b Qiú 2000, p.139.
- ^ Qiú 2000 p.113 & 139.
- ^ Qiú 2000, p.140–1 mentions examples of neo-clerical with “strong overtones of cursive script” from the late E. Hàn.
- ^ Qiú 2000 p.142.
- ^ Liú is then said to have taught Zhōng Yáo and Wáng Xīzhī.
- ^ Transcript of lecture 《楷法無欺》 by 田英章. Retrieved 2010-05-22.
- ^ a b Qiú 2000, p.143.
- ^ Qiú 2000, p.144.
- ^ Qiú 2000, p.148.
- ^ Wáng Xīzhī is so credited by essays by other calligraphers in the 6th to early 7th centuries, and most of his extant pieces are in modern cursive script (Qiú 2000, p.148).
- ^ Qiú 2000, p.145.
- ^ http://www.tiaccwhf.net/~t038/kaho/newpage82.htm
- ^ http://en.wikipedia.org/w/index.php?title=Image:Chinese_Pictographs.ogg&oldid=184680243
- ^ Handbook of Ancient Pronunciations of Chinese Characters (漢字古音手册), Guo, Xi-liang, Peking Univ. Press, 1986.
- ^ The Origin and Early Development of the Chinese Writing System, William G. Boltz, pp. 104–110, ISBN 0-940490-18-8.
- ^ Database query to Chinese characters - 沖 by Sergei Starostin
- ^ Database query to Chinese characters - 中 by Sergei Starostin
- ^ http://www.cflac.org.cn/chinaartnews/2003-10/08/content_1024511.htm
- ^ http://www.huaxia.com/ssjn/smxx/00197002.html
- ^ Updated from Norman, Jerry. Chinese. New York: Cambridge University Press. 1988, p. 72. ISBN 0521296536.
- ^ 《異體字字典》網路版說明 Official website for "The Dictionary of Chinese Variant Form", Introductory page
- ^ Hida & Sugawara, 1990, Tokyodo Shuppan.
- ^ Hakka Dictionary
- ^
(U+9F49) nàng is found, for instance, on p.707 of 漢英辭典(修訂版) A Chinese-English Dictionary, (Revised Edition) Foreign Language Teaching and Research Press, Beijing, 1995. ISBN 7-5600-0739-2. - ^ http://www.mojikyo.gr.jp/gif96/066/066147.gif
[edit] External links
 | Wikimedia Commons has media related to: Chinese Characters |
- Chinese Text Project Dictionary Comprehensive character dictionary including data for all Chinese characters in Unicode, and exemplary usage from early Chinese texts.
- A searchable dictionary with information about character formation (the characters are in GIF format)
- A learning tool that is focused on Chinese and Japanese character learning with stroke-by-stroke feedback, tone practice, audio files, and definition practice (Skritter.com).
- An online search engine by compound for characters, with example sentences in Chinese/Japanese/Shanghainese and their translations in several languages.
- Chinese Character Visual/Audio Dictionary: A dictionary sorted by frequency, with sound files, Chinese characters are found by typing Pinyin or copying and pasting characters.
- Art of Chinese Calligraphy
- Simplified Chinese Character Stroke Order and Dictionary: Stroke order animations, dictionary and writing worksheets for every simplified Chinese character in the national standard character set.
- History of Chinese writing
- websaru English Chinese dictionary Online Chinese dictionary with couples of Chinese learning aid tools.
- Chinese / English / French online characters Dictionary-Online Chinese/English/French characters Dictionary, Chinese tons, Chinese language learning resources, Chinese Exercises
- Chinese character etymologies
- Evolution of Chinese Characters
- Unihan Database: Chinese, Japanese, and Korean references, readings, and meanings for all the Chinese and Chinese-derived characters in the Unicode character set
- Chinese Character Test: Online test helps you estimate how many Chinese characters you recognize.
- IRG working documents—many big size pdfs, some of them with details of CJK extensions
- Welcome To Mojikyo Institute!—big size downloadable Mojikyo program files
- Stroke order for Chinese characters: Official website for stroke order for Chinese characters
- Chinese Characters: Suggestions about How to Learn Chinese Character
- English Words to Chinese Characters: A large list of English words translated into Chinese characters
- [1]: "Bodyworld's" Dr Gunther Von Hagens, who lives in Dalian, China, teaches me Chinese language system in mid-flight tutorial on a Lufthansa aeroplane" article, by Sam Beatson, MSc in Chinese language, business and international relations.
- Chinese Characters: Explanation of the forms of Chinese Characters; of their ideographic nature. Based on the Shuo Wen, other traditional sources and modern archeological finds.
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