Combining Texts

All the ideas for 'Gentzen's Analysis of First-Order Proofs', 'Against the Logicians (two books)' and 'The Theory of Knowledge'

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12 ideas

1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
Ordinary speech is not exact about what is true; we say we are digging a well before the well exists [Sext.Empiricus]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
Logic is based on transitions between sentences [Prawitz]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
Logical constants seem to be entities in propositions, but are actually pure form [Russell]
We use logical notions, so they must be objects - but I don't know what they really are [Russell]
Natural deduction introduction rules may represent 'definitions' of logical connectives [Prawitz]
5. Theory of Logic / H. Proof Systems / 4. Natural Deduction
In natural deduction, inferences are atomic steps involving just one logical constant [Prawitz]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
Logical truths are known by their extreme generality [Russell]
7. Existence / D. Theories of Reality / 8. Facts / d. Negative facts
There can't be a negative of a complex, which is negated by its non-existence [Potter on Russell]
9. Objects / D. Essence of Objects / 9. Essence and Properties
Some properties are inseparable from a thing, such as the length, breadth and depth of a body [Sext.Empiricus]
13. Knowledge Criteria / A. Justification Problems / 1. Justification / b. Need for justification
Fools, infants and madmen may speak truly, but do not know [Sext.Empiricus]
13. Knowledge Criteria / C. External Justification / 3. Reliabilism / a. Reliable knowledge
Madmen are reliable reporters of what appears to them [Sext.Empiricus]
18. Thought / D. Concepts / 2. Origin of Concepts / b. Empirical concepts
We can only dream of a winged man if we have experienced men and some winged thing [Sext.Empiricus]