Combining Texts

All the ideas for 'Philosophical Fragments', 'An Introduction to Modal Logic' and 'Response to Slote'

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7 ideas

4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / b. Terminology of PL
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
The Law of Transposition says (P→Q) → (¬Q→¬P) [Hughes/Cresswell]
4. Formal Logic / B. Propositional Logic PL / 4. Soundness of PL
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
A system is 'weakly' complete if all wffs are derivable, and 'strongly' if theses are maximised [Hughes/Cresswell]
7. Existence / A. Nature of Existence / 5. Reason for Existence
I assume existence, rather than reasoning towards it [Kierkegaard]
10. Modality / A. Necessity / 2. Nature of Necessity
Nothing necessary can come into existence, since it already 'is' [Kierkegaard]
23. Ethics / C. Virtue Theory / 1. Virtue Theory / d. Virtue theory critique
Virtue theory needs an external standard to judge behaviour and character [Inwagen, by Statman]