Combining Philosophers

All the ideas for H.Putnam/P.Oppenheim, GE Hughes/M Cresswell and David H. Sanford

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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]
14. Science / D. Explanation / 2. Types of Explanation / g. Causal explanations
Not all explanations are causal, but if a thing can be explained at all, it can be explained causally [Sanford]
14. Science / D. Explanation / 2. Types of Explanation / j. Explanations by reduction
Six reduction levels: groups, lives, cells, molecules, atoms, particles [Putnam/Oppenheim, by Watson]
26. Natural Theory / C. Causation / 8. Particular Causation / c. Conditions of causation
A totality of conditions necessary for an occurrence is usually held to be jointly sufficient for it [Sanford]