15 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] |
18935 | Semantic theory should specify when an act of naming is successful [Sawyer] |
18945 | Millians say a name just means its object [Sawyer] |
18934 | Sentences with empty names can be understood, be co-referential, and even be true [Sawyer] |
18938 | Frege's compositional account of truth-vaues makes 'Pegasus doesn't exist' neither true nor false [Sawyer] |
18947 | Definites descriptions don't solve the empty names problem, because the properties may not exist [Sawyer] |
9544 | A system is 'weakly' complete if all wffs are derivable, and 'strongly' if theses are maximised [Hughes/Cresswell] |
411 | If we succeed in speaking the truth, we cannot know we have done it [Xenophanes] |
412 | If God had not created honey, men would say figs are sweeter [Xenophanes] |
1640 | The basic Eleatic belief was that all things are one [Xenophanes, by Plato] |
3055 | Xenophanes said the essence of God was spherical and utterly inhuman [Xenophanes, by Diog. Laertius] |
407 | Mortals believe gods are born, and have voices and clothes just like mortals [Xenophanes] |
408 | Ethiopian gods have black hair, and Thracian gods have red hair [Xenophanes] |