28 ideas
18806 | Frege thought traditional categories had psychological and linguistic impurities [Frege, by Rumfitt] |
8490 | First-level functions have objects as arguments; second-level functions take functions as arguments [Frege] |
8492 | Relations are functions with two arguments [Frege] |
13733 | Frege considered definite descriptions to be genuine singular terms [Frege, by Fitting/Mendelsohn] |
9874 | Contradiction arises from Frege's substitutional account of second-order quantification [Dummett on Frege] |
18252 | Real numbers are ratios of quantities, such as lengths or masses [Frege] |
18271 | We can't prove everything, but we can spell out the unproved, so that foundations are clear [Frege] |
10623 | Frege defined number in terms of extensions of concepts, but needed Basic Law V to explain extensions [Frege, by Hale/Wright] |
9975 | Frege ignored Cantor's warning that a cardinal set is not just a concept-extension [Tait on Frege] |
18165 | My Basic Law V is a law of pure logic [Frege] |
8487 | Arithmetic is a development of logic, so arithmetical symbolism must expand into logical symbolism [Frege] |
18899 | Frege takes the existence of horses to be part of their concept [Frege, by Sommers] |
4028 | Frege allows either too few properties (as extensions) or too many (as predicates) [Mellor/Oliver on Frege] |
23651 | Universals are not objects of sense and cannot be imagined - but can be conceived [Reid] |
23650 | Only individuals exist [Reid] |
23649 | No one thinks two sheets possess a single whiteness, but all agree they are both white [Reid] |
8489 | The concept 'object' is too simple for analysis; unlike a function, it is an expression with no empty place [Frege] |
11874 | Real identity admits of no degrees [Reid] |
23652 | We must first conceive things before we can consider them [Reid] |
9947 | Concepts are the ontological counterparts of predicative expressions [Frege, by George/Velleman] |
10319 | An assertion about the concept 'horse' must indirectly speak of an object [Frege, by Hale] |
8488 | A concept is a function whose value is always a truth-value [Frege] |
9190 | A concept is a function mapping objects onto truth-values, if they fall under the concept [Frege, by Dummett] |
13665 | Frege took the study of concepts to be part of logic [Frege, by Shapiro] |
9948 | Unlike objects, concepts are inherently incomplete [Frege, by George/Velleman] |
23648 | First we notice and name attributes ('abstracting'); then we notice that subjects share them ('generalising') [Reid] |
4972 | I may regard a thought about Phosphorus as true, and the same thought about Hesperus as false [Frege] |
8491 | The Ontological Argument fallaciously treats existence as a first-level concept [Frege] |