5 ideas
| 527 | Everything exists which anyone perceives [Metrodorus of Chios] |
| 23217 | All of our happiness and misery arises entirely from the brain [Hippocrates] |
| 17371 | Some kinds are very explanatory, but others less so, and some not at all [Devitt] |
| 17372 | The higher categories are not natural kinds, so the Linnaean hierarchy should be given up [Devitt] |
| 17373 | Species pluralism says there are several good accounts of what a species is [Devitt] |