Full Idea
The notion of sameness or identity that we are to elucidate is not that of any degree of qualitative similarity but of coincidence as a substance - a notion as primitive as predication.
Gist of Idea
We want to explain sameness as coincidence of substance, not as anything qualitative
Source
David Wiggins (Sameness and Substance [1980], Pre 2)
Book Reference
Wiggins,David: 'Sameness and Substance' [Blackwell 1980], p.4
A Reaction
This question invites an approach to identity through our descriptions of it, rather than to the thing itself. There is no problem in ontology of two substances being 'the same', because they are just one substance.
Related Idea
Idea 15969 Two things can never be identical, so there is no problem [Lewis]