Combining Texts

All the ideas for '', 'A Realistic Theory of Categories' and 'Investigations into Logical Deduction'

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6 ideas

5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic

11211

If a sound conclusion comes from two errors that cancel out, the path of the argument must matter [Rumfitt]

5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives

11210

Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt]

11212

The sense of a connective comes from primitively obvious rules of inference [Rumfitt]

5. Theory of Logic / H. Proof Systems / 4. Natural Deduction

13832

Natural deduction shows the heart of reasoning (and sequent calculus is just a tool) [Gentzen, by Hacking]

7. Existence / E. Categories / 3. Proposed Categories

13120

Chisholm divides things into contingent and necessary, and then individuals, states and non-states [Chisholm, by Westerhoff]

19. Language / F. Communication / 3. Denial

11214

We learn 'not' along with affirmation, by learning to either affirm or deny a sentence [Rumfitt]