  In the first part of this section (Sophist 254d–255e), the Stranger addresses question (1): Of what sort is each of the great kinds? He distinguishes each of the five kinds from one another, starting with being, change, and rest. Change and rest, as opposites, do not associate with each other; but being applies to both, since we say that both of them are. Being must be a third kind distinct from them, for if being, which applies to both opposites, were the same as either of them—say change—then when being applies to rest, by substitution rest would partake of its own opposite, which is impossible (Sophist 254d, with 249e–250c). The Stranger uses a similar argument to show that sameness and difference are distinct from change and rest (Sophist 254d–255b). Furthermore, being is distinct from sameness. They have to be different, because if they were not, when we say that change and rest both are, we could substitute “are” with “the same,” and change would be the same as rest (Sophist 255b–c). (Much more can be said about sameness: for discussion see, e.g., Lewis 1976, and de Vries 1988.)