9 ideas
| 10245 | One geometry cannot be more true than another [Poincaré] |
| 6417 | In 1921 Russell abandoned sense-data, and the gap between sensation and object [Russell, by Grayling] |
| 6474 | Seeing is not in itself knowledge, but is separate from what is seen, such as a patch of colour [Russell] |
| 6476 | We cannot assume that the subject actually exists, so we cannot distinguish sensations from sense-data [Russell] |
| 2792 | It is possible the world came into existence five minutes ago, complete with false memories [Russell] |
| 10486 | If we are rebuilding our ship at sea, we should jettison some cargo [Boolos on Neurath] |
| 8485 | We must always rebuild our ship on the open sea; we can't reconstruct it properly in dry-dock [Neurath] |
| 22326 | Knowledge needs more than a sensitive response; the response must also be appropriate [Russell] |
| 6475 | In perception, the self is just a logical fiction demanded by grammar [Russell] |