 One of the unclarities of the phrase “criterion of identity” is that it is never spelled out what the criterion is to be applied to. For example, is it a criterion to be applied to names of objects or to perceptual representations of objects or to the objects themselves? It is also unclear how strictly we are to understand “criterion”. In “Entity and identity” (published in 1976 and reprinted in Strawson 1997b) Strawson proposed being quite strict, limiting the phrase “criterion of identity” to cases where there either is an explicitly statable necessary and sufficient condition that does not use the identity relation, or one where the identity relation is only applied to constituent parts of the objects. This can be done for numbers and sets, but probably not for any kind of concrete objects. In 1997, he retracted that proposal in favor of the looser (and still undefined) general philosophical use of the term (1997a: 2–3). In contrast, Wiggins understands the counting criterion very strictly so one instance where there is not a determinate answer to a question leads him to reject the counting criterion (2001: 75).