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] |
9544 | A system is 'weakly' complete if all wffs are derivable, and 'strongly' if theses are maximised [Hughes/Cresswell] |
13165 | Geometrical proofs do not show causes, as when we prove a triangle contains two right angles [Proclus] |
9569 | The origin of geometry started in sensation, then moved to calculation, and then to reason [Proclus] |
6017 | Nomos is king [Pindar] |