10 ideas
| 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] |
| 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] |
| 7071 | Life and rationality are pointless if we can only contemplate the freedom of our own ego [Jacobi] |
| 7072 | Jacobi was the first philosopher to talk of nihilism [Jacobi, by Critchley] |
| 13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
| 20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |