Combining Texts

All the ideas for 'works', 'The History of Animals' and 'An Introduction to Modal Logic'

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8 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 / D. Assumptions for Logic / 3. Contradiction
10121 Contradiction is not a sign of falsity, nor lack of contradiction a sign of truth [Pascal]
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]
14. Science / D. Explanation / 2. Types of Explanation / k. Explanations by essence
15119 Aristotelian explanation by essence may need to draw on knowledge of other essences [Aristotle, by Koslicki]
27. Natural Reality / G. Biology / 2. Life
23302 Plants have far less life than animals, but more life than other corporeal entities [Aristotle]
27. Natural Reality / G. Biology / 3. Evolution
23301 There is a gradual proceeding from the inanimate to animals, with no clear borderlines [Aristotle]