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All the ideas for 'fragments/reports', 'fragments/reports' and 'An Introduction to Modal Logic'

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10 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]
10. Modality / A. Necessity / 10. Impossibility
5998 From the necessity of the past we can infer the impossibility of what never happens [Diod.Cronus, by White,MJ]
10. Modality / B. Possibility / 1. Possibility
20832 The Master Argument seems to prove that only what will happen is possible [Diod.Cronus, by Epictetus]
10. Modality / B. Possibility / 8. Conditionals / d. Non-truthfunction conditionals
14304 Conditionals are true when the antecedent is true, and the consequent has to be true [Diod.Cronus]
19. Language / D. Propositions / 4. Mental Propositions
6024 Thought is unambiguous, and you should stick to what the speaker thinks they are saying [Diod.Cronus, by Gellius]
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]
27. Natural Reality / G. Biology / 3. Evolution
5989 Archelaus said life began in a primeval slime [Archelaus, by Schofield]