more from Peter Geach

Single Idea 8775

[catalogued under 15. Nature of Minds / C. Capacities of Minds / 3. Abstraction by mind]

Full Idea

A big flea or rat is a small animal, and a small elephant is a big animal, so there can be no question of ignoring the kind of thing to which 'big' or 'small' is referred and forming those concepts by abstraction.

Gist of Idea

A big flea is a small animal, so 'big' and 'small' cannot be acquired by abstraction

Source

Peter Geach (Mental Acts: their content and their objects [1957], 9)

Book Reference

Geach,Peter: 'Mental Acts: Their content and their objects' [RKP 1971], p.32


A Reaction

Geach is attacking a caricature of the theory. Abstraction is a neat mental trick which has developed in stages, from big rats relative to us, to big relative to other rats, to the concept of 'relative' (Idea 8776!), to the concept of 'relative bigness'.

Related Idea

Idea 8776 We cannot learn relations by abstraction, because their converse must be learned too [Geach]