more from this thinker     |     more from this text

Single Idea 18950

[filed under theme 9. Objects / A. Existence of Objects / 2. Abstract Objects / b. Need for abstracta ]

Full Idea

Physics is full of references to such 'non-physical' entities as state-vectors, Hamiltonians, Hilbert space etc.

Gist of Idea

Physics is full of non-physical entities, such as space-vectors

Source

Hilary Putnam (Philosophy of Logic [1971], Ch.2)

Book Ref

Putnam,Hilary: 'Philosophy of Logic' [Routledge 1972], p.14

A Reaction

I take these to be concepts which are 'abstracted' from the physical facts, and so they don't strike me as being much of an ontological problem, or an objection to nominalism (which Putnam takes them to be).

The 5 ideas with the same theme [why we might postulate non-physical objects]:

13387 Our conceptual scheme becomes more powerful when we posit abstract objects [Quine]
16980 We need a logical use of 'object' as predicate-worthy, and an 'ontological' use [Strawson,P]
18950 Physics is full of non-physical entities, such as space-vectors [Putnam]
10555 If we can intuitively apprehend abstract objects, this makes them observable and causally active [Dummett]
18067 Abstract objects were a bad way of explaining the structure in mathematics [Kitcher]