 As an object or what is real or factual, shí contrasts not with “subject” or “subjective,” but with xū 虛 (empty, hollow, insubstantial, indeterminate) or with míng 名 (name), the linguistic label for the thing referred to. Nor is shí “substance,” as contrasted with a set of properties that are in, possessed by, or realized by it. What we think of as the properties of a shí are all just inherent parts of it. Instead of positing an essence or a set of essential properities instantiated by all things of a kind, the Mohists take it as a brute fact that shí may be similar or different in various respects, and they seek criteria by which to divide them into kinds based on these similarities and differences. As we will discuss when we consider the notions of  “same” and   “different,”  features they cite as such criteria include “shape and look” (xíng mào 形貌), “residence and migration” (jū yùn 居運), and “amount and number” (liàng shù 量數) (NO2). Whether a particular thing falls within a certain kind, and thus takes a certain name, such as ‘horse’, is determined by comparing it with a fǎ 法 (model, exemplar) of that kind to see whether they are similar (A70). A particular horse counts a horse because its “look” or “characteristics” (mào 貌) are “like the model” (A71). As we will see, in some places, the writers of the Canons seem to assume that such similarity relations are fixed by nature, though they do not give an explicit defense of this stance. 