Combining Texts

All the ideas for 'Through the Looking Glass', 'Causation' 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 / 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]
7. Existence / A. Nature of Existence / 3. Being / e. Being and nothing
21982 I only wish I had such eyes as to see Nobody! It's as much as I can do to see real people. [Carroll,L]
7. Existence / D. Theories of Reality / 8. Facts / a. Facts
8386 Events are picked out by descriptions, and facts by whole sentences [Crane]
26. Natural Theory / C. Causation / 4. Naturalised causation
8387 A cause has its effects in virtue of its properties [Crane]
26. Natural Theory / C. Causation / 9. General Causation / a. Constant conjunction
8384 The regularity theory explains a causal event by other items than the two that are involved [Crane]