7 ideas
| 8942 | Lukasiewicz's L3 logic has three truth-values, T, F and I (for 'indeterminate') [Lukasiewicz, by Fisher] |
| 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] |
| 6005 | Animals are dangerous and nourishing, and can't form contracts of justice [Hermarchus, by Sedley] |