3 ideas
17750 | The first clear proof of the consistency of the first order predicate logic was in 1928 [Hilbert/Ackermann, by Walicki] |
Full Idea: The first clear proof of the consistency of the first order predicate logic is found in the 1928 book of Hilbert and Ackermann. | |
From: report of Hilbert,D/Ackermann,W (Principles of Theoretical Logic [1928]) by Michal Walicki - Introduction to Mathematical Logic History E.2.1 |
9567 | Maths deals with quantities of physical significance, ignoring irrelevant features [Geroch] |
Full Idea: Mathematics can serve to provide a framework within which one deals only with quantities of physical significance, ignoring other, irrelevant things. | |
From: Robert Geroch (Mathematical Physics [1985], p.1), quoted by Charles Chihara - A Structural Account of Mathematics 9.8 | |
A reaction: This is a modern physicist espousing abstractionism, as derided and dismissed by Frege and Geach. It's common sense, really. |
1513 | The Egyptians were the first to say the soul is immortal and reincarnated [Herodotus] |
Full Idea: The Egyptians were the first to claim that the soul of a human being is immortal, and that each time the body dies the soul enters another creature just as it is being born. | |
From: Herodotus (The Histories [c.435 BCE], 2.123.2) |