Combining Texts

All the ideas for 'fragments/reports', 'On Sufficient Reason' and 'Gentzen's Analysis of First-Order Proofs'

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

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7 ideas

2. Reason / B. Laws of Thought / 1. Laws of Thought

19404

Necessities rest on contradiction, and contingencies on sufficient reason [Leibniz]

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

13831

Logic is based on transitions between sentences [Prawitz]

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

13825

Natural deduction introduction rules may represent 'definitions' of logical connectives [Prawitz]

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

13823

In natural deduction, inferences are atomic steps involving just one logical constant [Prawitz]

26. Natural Theory / A. Speculations on Nature / 5. Infinite in Nature

1748	Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius]

26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / c. Essence and laws

19403

Each of the infinite possible worlds has its own laws, and the individuals contain those laws [Leibniz]

27. Natural Reality / G. Biology / 3. Evolution

5989	Archelaus said life began in a primeval slime [Archelaus, by Schofield]