7 ideas
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] |
9541 | The Law of Transposition says (P→Q) → (¬Q→¬P) [Hughes/Cresswell] |
9543 | The rules preserve validity from the axioms, so no thesis negates any other thesis [Hughes/Cresswell] |
9465 | Substitutional universal quantification retains truth for substitution of terms of the same type [Jacquette] |
9466 | Nominalists like substitutional quantification to avoid the metaphysics of objects [Jacquette] |
9544 | A system is 'weakly' complete if all wffs are derivable, and 'strongly' if theses are maximised [Hughes/Cresswell] |
1556 | By nature people are close to one another, but culture drives them apart [Hippias] |