Contemporary discussions of meaning and reference, and general recognition of the need for distinguishing between them, derive from Frege’s famous essay on the subject. That essay begins by considering the peculiar nature of statements of identity. If we say that A is identical with B it seems that what we say must-be either trivial, if it simply identifies A with itself, or false, if it identifies A with something other than itself. Frege’s solution is that a substantial statement of identity must contain two singular terms that differ in meaning but which will, if the statement is true, have exactly the same reference. A further feature of identity statements about concrete individuals that has come to be recognised is that the A and B of an identity-statement must be taken to fall under or be instances of the same substantival concept of a thing or natural kind (cf. Geach (2), p. 39). What makes an identity-statement of this kind true is the reference by the singular terms involved to individuals at the same position. No doubt our evidence of identity is often a matter of strictly qualitative identity but what it is evidence for is identity of position.