9 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] |
15533 | We can quantify over fictions by quantifying for real over their names [Lewis] |
15534 | We could quantify over impossible objects - as bundles of properties [Lewis] |
9544 | A system is 'weakly' complete if all wffs are derivable, and 'strongly' if theses are maximised [Hughes/Cresswell] |
15532 | 'Allists' embrace the existence of all controversial entities; 'noneists' reject all but the obvious ones [Lewis] |
15535 | We can't accept a use of 'existence' that says only some of the things there are actually exist [Lewis] |
3536 | Supervenient properties must have matching base properties [Kim] |