Combining Texts

All the ideas for 'Specimen inventorum', 'Knowledge by Acquaintance and Description-1' and 'Investigations into Logical Deduction'

expand these ideas     |    start again     |     specify just one area for these texts

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4 ideas

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]

8. Modes of Existence / D. Universals / 2. Need for Universals

21710

We know a universal in 'yellow differs from blue' or 'yellow resembles blue less than green does' [Russell]

12. Knowledge Sources / B. Perception / 4. Sense Data / d. Sense-data problems

8854	My 'acquaintance' with sense-data is nothing like my knowing New York [Williams,M on Russell]

14. Science / D. Explanation / 2. Types of Explanation / k. Explanations by essence

12729

The cause of a change is not the real influence, but whatever gives a reason for the change [Leibniz]