5 ideas
| 18086 | Weierstrass eliminated talk of infinitesimals [Weierstrass, by Kitcher] |
| Full Idea: Weierstrass effectively eliminated the infinitesimalist language of his predecessors. | |
| From: report of Karl Weierstrass (works [1855]) by Philip Kitcher - The Nature of Mathematical Knowledge 10.6 |
| 18092 | Weierstrass made limits central, but the existence of limits still needed to be proved [Weierstrass, by Bostock] |
| Full Idea: After Weierstrass had stressed the importance of limits, one now needed to be able to prove the existence of such limits. | |
| From: report of Karl Weierstrass (works [1855]) by David Bostock - Philosophy of Mathematics 4.4 | |
| A reaction: The solution to this is found in work on series (going back to Cauchy), and on Dedekind's cuts. |
| 20921 | How can we state relativism of sweet and sour, if they have no determinate nature? [Theophrastus] |
| Full Idea: How could what is bitter for us be sweet and sour for others, if there is not some determinate nature for them? | |
| From: Theophrastus (On the Senses [c.321 BCE], 70) | |
| A reaction: The remark is aimed at Democritus. This is part of the general question of how you can even talk about relativism, without attaching stable meanings to the concepts employed. |
| 20653 | Six reduction levels: groups, lives, cells, molecules, atoms, particles [Putnam/Oppenheim, by Watson] |
| Full Idea: There are six 'reductive levels' in science: social groups, (multicellular) living things, cells, molecules, atoms, and elementary particles. | |
| From: report of H.Putnam/P.Oppenheim (Unity of Science as a Working Hypothesis [1958]) by Peter Watson - Convergence 10 'Intro' | |
| A reaction: I have the impression that fields are seen as more fundamental that elementary particles. What is the status of the 'laws' that are supposed to govern these things? What is the status of space and time within this picture? |
| 5990 | Theophrastus doubted whether nature could be explained teleologically [Theophrastus, by Gottschalk] |
| Full Idea: Theophrastus questioned Aristotle's teaching on the extent to which teleological explanations could be applied to the natural world. | |
| From: report of Theophrastus (On Metaphysics (frags) [c.320 BCE]) by H.B. Gottschalk - Aristotelianism | |
| A reaction: It is interesting to see that Aristotle's own immediate successor had doubts about teleology. We usually assume that the ancients were teleological, and this was rejected in the seventeenth century (e.g. Idea 4826). |