4 ideas
8923 | Numbers are identified by their main properties and relations, involving the successor function [MacBride] |
Full Idea: The mathematically significant properties and relations of natural numbers arise from the successor function that orders them; the natural numbers are identified simply as the objects that answer to this basic function. | |
From: Fraser MacBride (Structuralism Reconsidered [2007], §1) | |
A reaction: So Julius Caesar would be a number if he was the successor of Pompey the Great? I would have thought that counting should be mentioned - cardinality as well as ordinality. Presumably Peano's Axioms are being referred to. |
13007 | Archimedes defined a straight line as the shortest distance between two points [Archimedes, by Leibniz] |
Full Idea: Archimedes gave a sort of definition of 'straight line' when he said it is the shortest line between two points. | |
From: report of Archimedes (fragments/reports [c.240 BCE]) by Gottfried Leibniz - New Essays on Human Understanding 4.13 | |
A reaction: Commentators observe that this reduces the purity of the original Euclidean axioms, because it involves distance and measurement, which are absent from the purest geometry. |
8926 | For mathematical objects to be positions, positions themselves must exist first [MacBride] |
Full Idea: The identification of mathematical objects with positions in structures rests upon the prior credibility of the thesis that positions are objects in their own right. | |
From: Fraser MacBride (Structuralism Reconsidered [2007], §3) | |
A reaction: Sounds devastating, but something has to get the whole thing off the ground. This is why Resnik's word 'patterns' is so appealing. Patterns stare you in the face, and they don't change if all the objects making it up are replaced by others. |
6011 | There is a remote first god (the Good), and a second god who organises the material world [Numenius, by O'Meara] |
Full Idea: Numenius argues that material reality depends on intelligible being, which depends on a first god - the Good - which is difficult to grasp, but which inspires a second god to imitate it, turning to matter and organizing it as the world. | |
From: report of Numenius (fragments/reports [c.160]) by Dominic J. O'Meara - Numenius | |
A reaction: The interaction problem comes either between the two gods, or between the second god and the world. The argument may have failed to catch on for long when people scented an infinite regress lurking in the middle of it. |