9 ideas
| 15380 | Barcan:nothing comes into existence; Converse:nothing goes out; Both:domain is unchanging [Vervloesem] |
| 15148 | Powers give explanations, without being necessary for some class membership [Chakravartty] |
| 594 | Speusippus suggested underlying principles for every substance, and ended with a huge list [Speussipus, by Aristotle] |
| 15145 | A kind essence is the necessary and sufficient properties for membership of a class [Chakravartty] |
| 15147 | Cluster kinds are explained simply by sharing some properties, not by an 'essence' [Chakravartty] |
| 15144 | Explanation of causal phenomena concerns essential kinds - but also lack of them [Chakravartty] |
| 15146 | Some kinds, such as electrons, have essences, but 'cluster kinds' do not [Chakravartty] |
| 15151 | Many causal laws do not refer to kinds, but only to properties [Chakravartty] |
| 2632 | Speusippus said things were governed by some animal force rather than the gods [Speussipus, by Cicero] |