The dialogue is between two unnamed speakers.
Can it be that a white horse is not a horse?This dialogue continues with deliberations over colored and colorless horses and whether "white" and "horse" can be separated from "white horse".
Advocate: It can.
Advocate: "Horse" is that by means of which one names the shape. "White" is that by means of which one names the color. What names the color is not what names the shape. Hence, I say that a white horse is not a horse.
Objector: If there are white horses, one cannot say that there are no horses. If one cannot say that there are no horses, doesn't that mean that there are horses? For there to be white horses is for there to be horses. How could it be that the white ones are not horses?
Advocate: If one wants a horse, that extends to a yellow or black horse. But if one wants a white horse, that does not extend to a yellow or black horse. Suppose that a white horse were a horse. Then what one wants [in the two cases] would be the same. If what one wants were the same, then a white [horse] would not differ from a horse. If what one wants does not differ, then how is it that a yellow or black horse is sometimes acceptable and sometimes unacceptable? It is clear that acceptable and unacceptable are mutually contrary. Hence, yellow and black horses are the same [in that, if there are yellow or black horses], one can respond that there are horses, but one cannot respond that there are white horses. Thus, it is evident that a white horse is not a horse. … (tr. Van Norden 2005:364-5)
Other Gongsun longzi chapters discuss Baima-related concepts of jian 堅 "hard; hardness" and bai 白 "white; whiteness", ming 名 "name; term" and shi 實 "solid; true, actual; fact, reality", and abstract zhi 指 "finger; pointing; designation; universal" like "whiteness" and concrete wu 物 "thing; object; particular" like a "white horse".
Chinese Baima fei ma 白馬非馬 syntactically hinges upon the negative fei 非 "not, is not; no, negative; oppose; wrong". The Classical construction "A fei B" "A非B" can ambiguously mean either "A is not a member of the class B" or "A is not identical to B". Interpreting this equivocation fallacy, A.C. Graham says this "white horse" vs. "horse" paradox plays upon the ambiguity of whether "is" means:
For example, the celebrated "Happiness of Fish" dialogue in Zhuangzi (17, tr. Watson 1968:188-9) contrasts both meanings. Huizi says "You're not a fish [子非魚] — how do you know what fish enjoy?" and Zhuangzi replies "You're not I [子非我], so how do you know I don't know what fish enjoy?"
Beyond the inherent semantic ambiguities of Baima fei ma, the first line obscurely asks ke hu 可乎 "Can it be that …?". This dialogue could be an attempted proof that a white horse is not a horse, or a question if such a statement is possible, or both. Van Norden suggests "that the issue is not whether it is always true that 'a white horse is not a horse,' but whether it is possible for it to be true."
Strictly speaking, names or terms are divided into those that are abstract and those that are concrete. The abstract term denotes the universal, the concrete term the particular. The particular is the denotation, and the universal the connotation, of the term. In western inflected languages there is no difficulty in distinguishing between the particular ('white' or 'horse') and the abstract ('whiteness' or 'horseness'). In Chinese, however, owing to the fact that the written characters are ideographic and pictorial and lack all inflection, there is no possible way, as far as the form of individual words is concerned, of distinguishing between abstract and concrete terms. Thus in Chinese the word designating a particular horse and that designating the universal, 'horseness,' are written and pronounced in the same way. Similarly with other terms, so that such words as 'horse' and 'white', being used to designate both the concrete particular and the abstract universal, thus hold two values. (1952:206)
Despite these interpretative difficulties with the White Horse Dialogue, many philosophers and sinologists have analyzed it. For instance, see Hansen (1976, 1983:140-); Graham (1989:75-95), (1990:125-216); Thompson (1995); Harbsmeier (1998:298-321); and Van Norden (2005:363-367).
On the Asian philosophical side, the Baima Lun's significance is evident from how many Chinese classic texts directly or indirectly discuss it. The Liezi (chapter 4, tr. Graham 1990:88), which lists and criticizes the paradoxes of Gongsun Long as "perversions of reason and sense", explains "'A white horse is not a horse', because the name diverges from the shape." Two Zhuangzi chapters (17 and 33) mock Gongsun Long, and another (2) combines his zhi 指 "attribute" and ma 馬 "horse" notions in the same context.
To use an attribute to show that attributes are not attributes is not as good as using a nonattribute to show that attributes are not attributes. To use a horse to show that a horse is not a horse is not as good as using a non-horse to show that a horse is not a horse, Heaven and earth are one attribute; the ten thousand things are one horse. (tr. Burton Watson, 1964:35)The Mengzi (6A) uses bai 白 "white" to mean both "white-haired; old (person)" and "white-colored (horse)".
Mencius said, 'There is no difference between our pronouncing a white horse to be white and our pronouncing a white man to be white. But is there no difference between the regard with which we acknowledge the age of an old horse and that with which we acknowledge the age of an old man? And what is it which is called righteousness? The fact of a man's being old? Or the fact of our giving honour to his age?' (tr. James Legge)Other early "A white horse is not a horse" references are found in the Hanfeizi (32), Mozi (11B), and Zhanguoce (4).
On the European philosophical side, whether "a white horse is not a horse" entails diverse philosophical concepts including Platonic idealism, Substance theory, logical intension or comprehension versus extension or denotation, and the Primary/secondary quality distinction in epistemology.