8 ideas
| 18270 | Choice suggests that intensions are not needed to ensure classes [Coffa] |
| Full Idea: The axiom of choice was an assumption that implicitly questioned the necessity of intensions to guarantee the presence of classes. | |
| From: J. Alberto Coffa (The Semantic Tradition from Kant to Carnap [1991], 7 'Log') | |
| A reaction: The point is that Choice just picks out members for no particular reason. So classes, it seems, don't need a reason to exist. |
| 16974 | The nature of each logical concept is given by a collection of inference rules [Correia] |
| Full Idea: The view presented here presupposes that each logical concept is associated with some fixed and well defined collection of rules of inference which characterize its basic logical nature. | |
| From: Fabrice Correia (On the Reduction of Necessity to Essence [2012], 4) | |
| A reaction: [He gives Fine's 'Senses of Essences' 57-8 as a source] He seems to have in mind natural deduction, where the rules are for the introduction and elimination of the concepts. |
| 16973 | Explain logical necessity by logical consequence, or the other way around? [Correia] |
| Full Idea: One view is that logical consequence is to be understood in terms of logical necessity (some proposition holds necessarily, if some group of other propositions holds). Alternatively, logical necessity is a logical consequence of the empty set. | |
| From: Fabrice Correia (On the Reduction of Necessity to Essence [2012], 3) | |
| A reaction: I think my Finean preference is for all necessities to have a 'necessitator', so logical necessity results from logic in some way, perhaps from logical consequence, or from the essences of the connectives and operators. |
| 18263 | The semantic tradition aimed to explain the a priori semantically, not by Kantian intuition [Coffa] |
| Full Idea: The semantic tradition's problem was the a priori; its enemy, Kantian pure intuition; its purpose, to develop a conception of the a priori in which pure intuition played no role; its strategy, to base that theory on a development of semantics. | |
| From: J. Alberto Coffa (The Semantic Tradition from Kant to Carnap [1991], 2 Intro) | |
| A reaction: It seems to me that intuition, in the modern sense, has been unnecessarily demonised. I would define it as 'rational insights which cannot be fully articulated'. Sherlock Holmes embodies it. |
| 18272 | Platonism defines the a priori in a way that makes it unknowable [Coffa] |
| Full Idea: The trouble with Platonism had always been its inability to define a priori knowledge in a way that made it possible for human beings to have it. | |
| From: J. Alberto Coffa (The Semantic Tradition from Kant to Carnap [1991], 7 'What') | |
| A reaction: This is the famous argument of Benacerraf 1973. |
| 18266 | Mathematics generalises by using variables [Coffa] |
| Full Idea: The instrument of generality in mathematics is the variable. | |
| From: J. Alberto Coffa (The Semantic Tradition from Kant to Carnap [1991], 4 'The conc') | |
| A reaction: I like the idea that there are variables in ordinary speech, pronouns being the most obvious example. 'Cats' is a variable involving quantification over a domain of lovable fluffy mammals. |
| 468 | Musical performance can reveal a range of virtues [Damon of Ath.] |
| Full Idea: In singing and playing the lyre, a boy will be likely to reveal not only courage and moderation, but also justice. | |
| From: Damon (fragments/reports [c.460 BCE], B4), quoted by (who?) - where? |
| 18279 | Relativity is as absolutist about space-time as Newton was about space [Coffa] |
| Full Idea: If the theory of relativity might be thought to support an idealist construal of space and time, it is no less absolutistic about space-time than Newton's theory was about space. | |
| From: J. Alberto Coffa (The Semantic Tradition from Kant to Carnap [1991]) | |
| A reaction: [He cites Minkowski, Weyl and Cartan for this conclusion] Coffa is clearly a bit cross about philosophers who draw naive idealist and relativist conclusions from relativity. |