"Technically, classical China had semantic theory but no logic. Western historians, confusing logic and theory of language, used the term 'logicians' to describe those philosophers
whom the Chinese called the 'name school'. The best known of these were Hui Shi (380-305 b. C.) and Gongsun Lung (b. 380 b. C.?). This group now also includes the Later Mohists and the term
'distinction school' (translated as 'dialecticians') has become common.
The importance of the more detailed Mohist work came to light in modern times. The Confucian tradition had lost access to it. Rescuing that text rekindled a long-lost interest in
Chinese theories of language. The restored Mohist texts give us a general theory of how words work. A term picks out part of reality. Some terms are more general than others; terms like 'dobbin' or
'horse' or 'object' might pick out the same thing. When we use a term to pick something out, we commit ourselves to using the name to pick out similar things and 'stopping' with the dissimilar. Thus,
for each term we learn an 'is this' and an 'is not'. 'Is not' generates an opposite for each name and marks the point of distinction or discrimination.
Chinese doctrine portrays disagreements as arising from different ways of making the distinctions that give rise to opposites. The word bian
(distinction/dispute) thus came to stand for a philosophical dispute. The Mohists argued that, in a 'distinction/dispute', one party will always be right. For any descriptive term, the thing in
question will either be an 'is this' or an 'is not'. Mohists were realistic about descriptions and the world. Real similarities and differences underlie our language. They rejected the claim that
words distort reality; to regard all language as 'perverse', they noted, was 'perverse'. The Mohists failed, however, to give a good account of what similarities and differences should count in
making a distinction. Mohists also found that combining terms was semantically fickle. In the simplest case, the compound picked out the sum of what the individual terms did. Classical Chinese lacked
pluralization so 'cat-dog' works like 'cats and dogs'. Other compound terms (such as 'white horse') worked as they do in English. The confusion led Gongsun Long to argue, on Confucian grounds, that
we could say 'white horse is not horse'."
From: Chad Hansen - Logic in China - in: Edward Craig (ed.) - Routledge Encyclopedia of Philosophy - London, New York:
Routledge 1998 pp. 694-695.
"Systematic argument in Chinese philosophy began with the Moist school, founded in the fifth century b. C. by the first anti-Confucian thinker Mo Tzu (c. 468 - c. 376 b. C.). He
laid down three tests for the validity of a doctrine: ancient authority, common observation, and practical effect. At first the controversies of the various schools over moral and political
principles led to increasing rigor in argument; then to an interest in dialectic for its own sake, as evidenced in Hui Shih's paradoxes of infinity and in Kung-sun Lung's sophism "A (white) horse is
not a horse"; and still later to the antirationalism of the Taoist Chuang Tzu (born c. 369 B.C.), who rejected all dialectic on the grounds that names have only an arbitrary connection with objects
and that any point of view is right for those who accept the choice of names it assumes.
Logic of Mohism. In the third century b.C. the Mohists responded to Chuang Tzu's skepticism by systematizing dialectic in the "Moist Canons" and the slightly later Ta-ch'ü and
Moist Canons. The "Canons" confined dialectic to questions of the form "Is it this or is it not?" or, since they assumed that the proposition is merely a complex name for a complex
object, "Is it or is it not the case that . . . ?" (The form is distinguished in Chinese by a verbless sentence with a final particle, not by a verb "to be.") In true dialectic the alternatives are
paired ("Is it an ox or not?") so that one and only one fits the object. Dialectic excludes such questions as "Is it an ox or a horse?" (it may be neither) and "Is it a puppy or a dog?" (it may be
both). Its solutions are absolutely right or wrong; being or not being "this," unlike being long or short, is not a matter of degree, since nothing is more "this" than this is. The Mohists further
argued that it is self-contradictory to deny or to affirm all propositions: the statement "All statements are mistaken" implies that it is itself mistaken, and one cannot "reject rejection" without
refusing to reject one's own rejection.
Names are of, three types, distinguished by their relations to "objects," which are assumed to be particular. "Unrestricted" names (such as "thing") apply to every object. Names "of
kinds" (such as "horse") apply to every object resembling the one in question. "Private" names (for example, the proper name "Tsang") apply to one object. Whether a name fits an object is decided by
appeal to a "standard." There may be more than one standard for an object; for "circle" the standard may be a circle, one's mental picture of a circle, or a compass. Some standards fit without
qualification: a circle has no straight lines. Some fit only partially: in deciding whether someone is a "black man" it is not enough to point out his black eyes and hair. The "Canons" began with 75
definitions, evidently offered as "standards," of moral, psychological, geometrical, and occasionally logical terms. An example of a definition of a logical term is "'All' is 'none not so' "
(supplemented in the Hsiao-ch'ü by " 'Some' is 'not all' "). The first of the series is "The 'cause' is what is required for something to happen." ("Minor cause: with this it will not necessarily be
so; without this it necessarily will not be so. Major cause: with this it will necessarily be so.") The "Canons" also distinguish the senses of 12 ambiguous terms. Thus, "same" is (1) identical ("two
names for one object"), (2) belonging to one body, (3) together, and (4) of a kind ("the same in some respects").
"Ta-ch'ü" and "Hsiao-ch'ü." The Moist Ta-ch'ü further refined the classification of names. Names indicating "number and measure" cease to apply when their objects are reduced in
size; when a white stone is broken up it ceases to be "big," although it is still "white." Names indicating "residence and migration" do not apply when the population moves, as in the case of names
of particular states ("Ch'i") or of kinds of administrative divisions ("country"). The claim that one knows X only if one knows that an object is X applies only to names indicating "shape and
appearance" ("mountain," but not "Ch'i" or "county").
The Ta-ch'ü, and still more the Hsiao-ch'ü, also showed a shift of interest from the name to the sentence and to the deduction of one sentence from another. The Chinese never
analyzed deductive forms, but the Mohists noticed that the formal parallelism of sentences does not necessarily entitle us to infer from one in the same way as from another, and they developed a
procedure for testing parallelism by the addition or substitution of words. For example, "Asking about a man's illness is asking about the man," but "Disliking the man's illness is not disliking the
man"; "The ghost of a man is not a man," but "The ghost of my brother is my brother." In order to reconcile the execution of robbers with love for all men some Mohists maintained that although a
robber is a man, "killing robbers is not killing men." Enemies of Mohism rejected this as sophistry, on the assumption that one can argue from "A robber is a man" to "Killing robbers is killing men,"
just as one can argue from "A white horse is a horse" to "Riding white horses is riding horses." The Hsiao-ch'ü replied that there are second and third sentence types of the same form, which do not
allow such an inference-for example, "Her brother is a handsome man," but "Loving her brother is not loving a handsome man"; "Cockfights are not cocks," but "Having a taste for cockfights is having a
taste for cocks." A four-stage procedure was used to establish that "A robber is a man" belongs to the second type:(1) Illustrating the topic ("robber") with things ("brother," "boat") of which
formally similar statements may be made.
(2) Matching parallel sentences about the illustrations and the topic-for instance, "Her brother is a handsome man, but loving her brother is not loving a handsome man"; "A boat is
wood, but entering a boat is not entering [piercing?] wood"; "A robber is a man, but abounding in robbers is not abounding in men, nor is being without robbers being without men."(3) Adducing
supporting arguments for the last and most relevant parallels by expanding them and showing that the parallelism still holds: "Disliking the abundance of robbers is not disliking the abundance of
men; wishing to be without robbers is not wishing to be without men."(4) Inferring, defined as "using its [the topic's] similarity to what he [the person being argued with] accepts in order to
propose what he does not accept": "Although a robber is a man, loving robbers is not loving men, not loving robbers is not loving men, and killing robbers is not killing men."
From: Angus C. Graham - Chinese logic - (Third section of: Logic, History of) in: Paul Edwards (ed.) - The Encyclopedia of
Philosophy - New York: Macmillan 1967. Vol. IV pp. 523-524.
(to be continued...)