8 ideas
| 8628 | I hold that algebra and number are developments of logic [Jevons] |
| 10496 | Monothetic categories have fixed defining features, and polythetic categories do not [Ellen] |
| 10497 | In symbolic classification, the categories are linked to rules [Ellen] |
| 10494 | Several words may label a category; one word can name several categories; some categories lack words [Ellen] |
| 10495 | Continuous experience sometimes needs imposition of boundaries to create categories [Ellen] |
| 10498 | Classification is no longer held to be rooted in social institutions [Ellen] |
| 20645 | Heat is a state of vibration, not a substance [Joule] |
| 20972 | Joule showed that energy converts to heat, and heat to energy [Joule, by Papineau] |