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Ideas for 'fragments/reports', 'Theaetetus' and 'Scientific Attitude and Fallibilism'

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3 ideas

6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / c. Counting procedure
Numbers are just names devised for counting [Peirce]
     Full Idea: Numbers are merely a system of names devised by men for the purpose of counting.
     From: Charles Sanders Peirce (Scientific Attitude and Fallibilism [1899], II)
     A reaction: This seems a perfectly plausible view prior to the advent of Cantor, set theory and modern mathematical logic. I suppose the modern reply to this is that Peirce may be right about origin, but that men thereby stumbled on an Aladdin's Cave of riches.
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / a. For mathematical platonism
We master arithmetic by knowing all the numbers in our soul [Plato]
     Full Idea: It must surely be true that a man who has completely mastered arithmetic knows all numbers? Because there are pieces of knowledge covering all numbers in his soul.
     From: Plato (Theaetetus [c.368 BCE], 198b)
     A reaction: This clearly views numbers as objects. Expectation of knowing them all is a bit startling! They also appear to be innate in us, and hence they appear to be Forms. See Aristotle's comment in Idea 645.
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / c. Against mathematical empiricism
That two two-eyed people must have four eyes is a statement about numbers, not a fact [Peirce]
     Full Idea: To say that 'if' there are two persons and each person has two eyes there 'will be' four eyes is not a statement of fact, but a statement about the system of numbers which is our own creation.
     From: Charles Sanders Peirce (Scientific Attitude and Fallibilism [1899], II)
     A reaction: One eye for each arm of the people is certainly a fact. Frege uses this equivalence to build numbers. I think Peirce is wrong. If it is not a fact that these people have four eyes, I don't know what 'four' means. It's being two pairs is also a fact.