Combining Texts

All the ideas for 'fragments/reports', 'An Introduction to Modal Logic' and 'On the Cosmos (lost)'

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12 ideas

4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / b. Terminology of PL
9540 A 'value-assignment' (V) is when to each variable in the set V assigns either the value 1 or the value 0 [Hughes/Cresswell]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / d. Basic theorems of PL
9541 The Law of Transposition says (P→Q) → (¬Q→¬P) [Hughes/Cresswell]
4. Formal Logic / B. Propositional Logic PL / 4. Soundness of PL
9543 The rules preserve validity from the axioms, so no thesis negates any other thesis [Hughes/Cresswell]
5. Theory of Logic / K. Features of Logics / 4. Completeness
9544 A system is 'weakly' complete if all wffs are derivable, and 'strongly' if theses are maximised [Hughes/Cresswell]
9. Objects / B. Unity of Objects / 1. Unifying an Object / a. Intrinsic unification
472 No things would be clear to us as entity or relationships unless there existed Number and its essence [Philolaus]
21. Aesthetics / C. Artistic Issues / 7. Art and Morality
468 Musical performance can reveal a range of virtues [Damon of Ath.]
26. Natural Theory / A. Speculations on Nature / 4. Mathematical Nature
1518 Everything must involve numbers, or it couldn't be thought about or known [Philolaus]
1519 Harmony must pre-exist the cosmos, to bring the dissimilar sources together [Philolaus]
473 There is no falsehood in harmony and number, only in irrational things [Philolaus]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / d. The unlimited
469 Existing things, and hence the Cosmos, are a mixture of the Limited and the Unlimited [Philolaus]
26. Natural Theory / D. Laws of Nature / 6. Laws as Numerical
476 Self-created numbers make the universe stable [Philolaus]
27. Natural Reality / E. Cosmology / 1. Cosmology
1787 Philolaus was the first person to say the earth moves in a circle [Philolaus, by Diog. Laertius]