32 ideas
| 21544 | It seems that when a proposition is false, something must fail to subsist [Russell] |
| 21539 | Excluded middle can be stated psychologically, as denial of p implies assertion of not-p [Russell] |
| 21538 | If two people perceive the same object, the object of perception can't be in the mind [Russell] |
| 17377 | All descriptive language is classificatory [Dupré] |
| 17376 | We should aim for a classification which tells us as much as possible about the object [Dupré] |
| 21534 | The only thing we can say about relations is that they relate [Russell] |
| 21540 | Relational propositions seem to be 'about' their terms, rather than about the relation [Russell] |
| 21536 | When I perceive a melody, I do not perceive the notes as existing [Russell] |
| 21535 | Objects only exist if they 'occupy' space and time [Russell] |
| 17390 | Natural kinds don't need essentialism to be explanatory [Dupré] |
| 17389 | A species might have its essential genetic mechanism replaced by a new one [Dupré] |
| 17388 | It seems that species lack essential properties, so they can't be natural kinds [Dupré] |
| 21533 | Contingency arises from tensed verbs changing the propositions to which they refer [Russell] |
| 21537 | I assume we perceive the actual objects, and not their 'presentations' [Russell] |
| 21532 | Full empiricism is not tenable, but empirical investigation is always essential [Russell] |
| 17374 | The possibility of prediction rests on determinism [Dupré] |
| 21542 | Do incorrect judgements have non-existent, or mental, or external objects? [Russell] |
| 21541 | The complexity of the content correlates with the complexity of the object [Russell] |
| 17378 | Presumably molecular structure seems important because we never have the Twin Earth experience [Dupré] |
| 21543 | If p is false, then believing not-p is knowing a truth, so negative propositions must exist [Russell] |
| 1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
| 17381 | Phylogenetics involves history, and cladism rests species on splits in lineage [Dupré] |
| 17385 | Kinds don't do anything (including evolve) because they are abstract [Dupré] |
| 17375 | Natural kinds are decided entirely by the intentions of our classification [Dupré] |
| 17379 | Borders between species are much less clear in vegetables than among animals [Dupré] |
| 17384 | Even atoms of an element differ, in the energy levels of their electrons [Dupré] |
| 17387 | Ecologists favour classifying by niche, even though that can clash with genealogy [Dupré] |
| 17382 | Cooks, unlike scientists, distinguish garlic from onions [Dupré] |
| 17380 | Wales may count as fish [Dupré] |
| 5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |
| 17383 | Species are the lowest-level classification in biology [Dupré] |
| 17386 | The theory of evolution is mainly about species [Dupré] |