Combining Texts

All the ideas for 'From Stimulus to Science', 'Set Theory and related topics (2nd ed)' and 'Necessary Existents'

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3 ideas

2. Reason / B. Laws of Thought / 3. Non-Contradiction
6564 To affirm 'p and not-p' is to have mislearned 'and' or 'not' [Quine]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / e. Equivalence classes
8920 Equivalence relations are reflexive, symmetric and transitive, and classify similar objects [Lipschutz]
19. Language / D. Propositions / 3. Concrete Propositions
19216 Propositions (such as 'that dog is barking') only exist if their items exist [Williamson]