Full Idea
Abstraction as a cognitive tool has been associated predominantly with the metaphysics of universals and of mathematical objects such as numbers. But it is more widely applicable beyond this standard range. I commend its judicious use.
Gist of Idea
Abstraction is usually seen as producing universals and numbers, but it can do more
Source
Peter Simons (Modes of Extension: comment on Fine [2008], p.21)
Book Reference
'Being: Developments in Contemporary Metaphysics', ed/tr. Le Poidevin,R [CUP 2008], p.21
A Reaction
Personally I think our view of the world is founded on three psychological principles: abstraction, idealisation and generalisation. You can try to give them rigour, as 'equivalence classes', or 'universal quantifications', if it makes you feel better.
Related Idea
Idea 18883 Any equivalence relation among similar things allows the creation of an abstractum [Simons]