Full Idea
Geach argued that the notion of absolute identity should be abandoned. ..We can only grasp the meaning of a count noun when we associate it with a criterion of identity, expressed by a particular relative identity sortal.
Clarification
'Sortals' are terms for things which can be counted
Gist of Idea
We should abandon absolute identity, confining it to within some category
Source
report of Peter Geach (Reference and Generality (3rd ed) [1980]) by John Hawthorne - Identity
Book Reference
'The Oxford Handbook of Metaphysics', ed/tr. Loux,M /Zimmerman,D [OUP 2005], p.111
A Reaction
In other words, identity needs categorisation. Hawthorne concludes that Geach is wrong. Geach clearly has much common usage on his side. 'What's that?' usually invites a categorisation. Sameness of objects seems to need a 'respect'.