6 ideas
21717 | Reducibility undermines type ramification, and is committed to the existence of functions [Quine, by Linsky,B] |
Full Idea: Quine charges that the axiom of Reducibility both undoes the effect of the ramification, and commits the theory to a platonist view of propositional functions (which is a theory of sets, once use/mention confusions are cleared up). | |
From: report of Willard Quine (Set Theory and its Logic [1963], p.249-58) by Bernard Linsky - Russell's Metaphysical Logic 6.1 |
18439 | Because things can share attributes, we cannot individuate attributes clearly [Quine] |
Full Idea: No two classes have exactly the same members, but two different attributes may be attributes of exactly the same things. Classes are identical when their members are identical. ...On the other hand, attributes have no clear principle of individuation. | |
From: Willard Quine (On the Individuation of Attributes [1975], p.100) |
18442 | You only know an attribute if you know what things have it [Quine] |
Full Idea: May we not say that you know an attribute only insofar as you know what things have it? | |
From: Willard Quine (On the Individuation of Attributes [1975], p.106) | |
A reaction: Simple, and the best defence of class nominalism (a very implausible theory) which I have encountered. Do I have to know all the things? Do I not know 'red' if I don't know tomatoes have it? |
18441 | No entity without identity (which requires a principle of individuation) [Quine] |
Full Idea: We have an acceptable notion of class, or physical object, or attribute, or any other sort of object, only insofar as we have an acceptable principle of individuation for that sort of object. There is no entity without identity. | |
From: Willard Quine (On the Individuation of Attributes [1975], p.102) | |
A reaction: Note that this is his criterion for an 'acceptable' notion. Presumably that is for science. It permits less acceptable notions which don't come up to the standard. And presumably true things can be said about the less acceptable entities. |
18440 | Identity of physical objects is just being coextensive [Quine] |
Full Idea: Physical objects are identical if and only if coextensive. | |
From: Willard Quine (On the Individuation of Attributes [1975], p.101) | |
A reaction: The supposed counterexample to this is the statue and the clay it is made of, which are said to have different modal properties (destroying the statue doesn't destroy the clay). |
19392 | I don't recommend universal doubt; we constantly seek reasons for things which are indubitable [Leibniz] |
Full Idea: I do not think it necessary to recommend to people universal doubt ...in fact, we are constantly seeking reasons for thoughts about which there is no doubt at all. | |
From: Gottfried Leibniz (Precepts for Advancing Science and Arts [1680], p.34) | |
A reaction: Such confidence is, of course, asking for trouble. I prefer Peirce's fallibilism - that robust realism is the most coherent view, and the only one worth pursuing and relying on, but you never know.... |