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Single Idea 23445

[filed under theme 4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / d. Naïve logical sets ]

Full Idea

Naïve set theory is based on the principles that any formula defines a set, and that coextensive sets are identical.

Gist of Idea

Naïve set theory says any formula defines a set, and coextensive sets are identical

Source

Øystein Linnebo (Philosophy of Mathematics [2017], 4.2)

Book Ref

Linnebo,Øystein: 'Philosophy of Mathematics' [Princeton 2017], p.62


A Reaction

The second principle is a standard axiom of ZFC. The first principle causes the trouble.


The 8 ideas from 'Philosophy of Mathematics'

Mathematics is the study of all possible patterns, and is thus bound to describe the world [Linnebo]
Logical truth is true in all models, so mathematical objects can't be purely logical [Linnebo]
Game Formalism has no semantics, and Term Formalism reduces the semantics [Linnebo]
The axioms of group theory are not assertions, but a definition of a structure [Linnebo]
To investigate axiomatic theories, mathematics needs its own foundational axioms [Linnebo]
Naïve set theory says any formula defines a set, and coextensive sets are identical [Linnebo]
You can't prove consistency using a weaker theory, but you can use a consistent theory [Linnebo]
In classical semantics singular terms refer, and quantifiers range over domains [Linnebo]