! " ! Copies and Occurrences

Copies are tokens of a single (type) expression and group together in virtue of having the same shape (i.e. they look alike). However, given common conceptions they are unlikely to be identical. For example, it is often assumed that movement is motivated by Greed and that the features of a moving expression change (get checked/valued) through the course of a derivation. 1 If so, the identity of the token cannot be calculated with respect to every feature (as the copies will differ on some). Rather some features must count more than others or copies must group in virtue of some version of feature non-distinctness rather than identity. Details aside, what is important here is that copies are grouped in terms of some intrinsic properties; they are copies of the same thing because they share a common relevant shape. 2