| 9834 | A class is, for Frege, the extension of a concept [Frege, by Dummett] |
| 3328 | Frege proposed a realist concept of a set, as the extension of a predicate or concept or function [Frege, by Benardete,JA] |
| 21563 | The 'no classes' theory says the propositions just refer to the members [Russell] |
| 14461 | Propositions about classes can be reduced to propositions about their defining functions [Russell] |
| 11020 | Realisms like the full Comprehension Principle, that all good concepts determine sets [Read] |
| 15919 | The 'logical' notion of class has some kind of definition or rule to characterise the class [Lavine] |