Combining Philosophers

Ideas for Anaxarchus, Theodore Sider and George Boolos

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2 ideas

6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order

10833

Many concepts can only be expressed by second-order logic [Boolos]

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A single second-order sentence validates all of arithmetic - but this can't be proved axiomatically [Sider]