4 ideas
10801 | Either reference really matters, or we don't need to replace it with substitutions [Quine] |
18431 | Internal relations combine some tropes into a nucleus, which bears the non-essential tropes [Simons, by Edwards] |
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] |