Combining Texts

All the ideas for 'On Motion', 'Commentary on 'Posterior Analytics'' and 'Hilbert's Programme'

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5 ideas

6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
Gödel showed that the syntactic approach to the infinite is of limited value [Kreisel]
     Full Idea: Usually Gödel's incompleteness theorems are taken as showing a limitation on the syntactic approach to an understanding of the concept of infinity.
     From: Georg Kreisel (Hilbert's Programme [1958], 05)
6. Mathematics / B. Foundations for Mathematics / 1. Foundations for Mathematics
The study of mathematical foundations needs new non-mathematical concepts [Kreisel]
     Full Idea: It is necessary to use non-mathematical concepts, i.e. concepts lacking the precision which permit mathematical manipulation, for a significant approach to foundations. We currently have no concepts of this kind which we can take seriously.
     From: Georg Kreisel (Hilbert's Programme [1958], 06)
     A reaction: Music to the ears of any philosopher of mathematics, because it means they are not yet out of a job.
9. Objects / B. Unity of Objects / 2. Substance / b. Need for substance
By comparing qualities and features, reason can gradually infer the nature of substance [Grosseteste]
     Full Idea: Awakened reason distinguishes color from size and shape from body and then shape and size from the substance of body, and so by drawing distinctions and abstracting, it arrives at a grasp of the substance of body, which supports size, shape and color.
     From: Robert Grosseteste (Commentary on 'Posterior Analytics' [1226], I.14), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 07.4
     A reaction: This optimistic view influenced Aquinas, and is called 'incrementalism' by Pasnau. It is the spirit of scientific essentialism, and a nice instance of inference to the best explanation (though 'substance' in itself explains virtually nothing).
27. Natural Reality / B. Modern Physics / 1. Relativity / a. Special relativity
Motion is not absolute, but consists in relation [Leibniz]
     Full Idea: In reality motion is not something absolute, but consists in relation.
     From: Gottfried Leibniz (On Motion [1677], A6.4.1968), quoted by Daniel Garber - Leibniz:Body,Substance,Monad 3
     A reaction: It is often thought that motion being relative was invented by Einstein, but Leibniz wholeheartedly embraced 'Galilean relativity', and refused to even consider any absolute concept of motion. Acceleration is a bit trickier than velocity.
27. Natural Reality / C. Space / 3. Points in Space
The natural conception of points ducks the problem of naming or constructing each point [Kreisel]
     Full Idea: In analysis, the most natural conception of a point ignores the matter of naming the point, i.e. how the real number is represented or by what constructions the point is reached from given points.
     From: Georg Kreisel (Hilbert's Programme [1958], 13)
     A reaction: This problem has bothered me. There are formal ways of constructing real numbers, but they don't seem to result in a name for each one.