5 ideas
| 8463 | Maths can be reduced to logic and set theory [Quine] |
| 6408 | Russell needed three extra axioms to reduce maths to logic: infinity, choice and reducibility [Grayling] |
| 8461 | The category of objects incorporates the old distinction of substances and their modes [Quine] |
| 6414 | Two propositions might seem self-evident, but contradict one another [Grayling] |
| 8462 | A hallucination can, like an ague, be identified with its host; the ontology is physical, the idiom mental [Quine] |