display all the ideas for this combination of texts
5 ideas
9457 | The two main views in philosophy of logic are extensionalism and intensionalism [Jacquette] |
Full Idea: Philosophy of logic has (roughly) two camps: extensionalists and intensionalists, with the former view dominant. ...There is a close connection between this and eliminativist or reductivist versus folk psychological and intentionalist philosophy of mind. | |
From: Dale Jacquette (Intro to 'Philosophy of Logic' [2002], §4) | |
A reaction: Hm. I think I favour intensionalism in the logic, and reductivism about the mind, so I may have a bit of bother here. I'm convinced that this jigsaw can be completed, despite all appearances. |
8195 | Undecidable statements result from quantifying over infinites, subjunctive conditionals, and the past tense [Dummett] |
Full Idea: I once wrote that there are three linguistic devices that make it possible for us to frame undecidable statements: quantification over infinity totalities, as expressed by word such as 'never'; the subjunctive conditional form; and the past tense. | |
From: Michael Dummett (Truth and the Past [2001], 4) | |
A reaction: Dummett now repudiates the third one. Statements containing vague concepts also appear to be undecidable. Personally I have no problems with deciding (to a fair extent) about 'never x', and 'if x were true', and 'it was x'. |
9458 | Extensionalists say that quantifiers presuppose the existence of their objects [Jacquette] |
Full Idea: Extensionalists hold that quantifiers in predicate logic presuppose the existence of whatever objects can be referred to by constants or bound variables, or enter into true predication of properties. | |
From: Dale Jacquette (Intro to 'Philosophy of Logic' [2002], §4) | |
A reaction: I have strong sales resistance to this view. Why should a procedure for correctly reasoning from one proposition to another have anything whatever to do with ontology? A false world picture can be interconnected by perfect logic. |
9461 | Intensionalists say meaning is determined by the possession of properties [Jacquette] |
Full Idea: According to intensionalist semantics the meaning of a proposition is determined by the properties an object possesses. | |
From: Dale Jacquette (Intro to 'Philosophy of Logic' [2002], §4) | |
A reaction: This sounds good to me. Extensionalist don't seem to care what sets they put things in, but if property possession comes first, then things will fall into their own sets without any help for us. We can add silly sets afterwards, if we fancy. |
8194 | Surely there is no exact single grain that brings a heap into existence [Dummett] |
Full Idea: There is surely no number n such that "n grains of sand do not make a heap, although n+1 grains of sand do" is true. | |
From: Michael Dummett (Truth and the Past [2001], 4) | |
A reaction: It might be argued that there is such a number, but no human being is capable of determing it. Might God know the value of n? On the whole Dummett's view seems the most plausible. |