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 |
| 17743 | De Morgan introduced a 'universe of discourse', to replace Boole's universe of 'all things' [De Morgan, by Walicki] |
| Full Idea: In 1846 De Morgan introduced the enormously influential notion of a possibly arbitrary and stipulated 'universe of discourse'. It replaced Boole's original - and metaphysically a bit suspect - universe of 'all things'. | |
| From: report of Augustus De Morgan (works [1846]) by Michal Walicki - Introduction to Mathematical Logic History D.1.1 | |
| A reaction: This not only brings formal logic under control, but also reflects normal talk, because there is always an explicit or implicit domain of discourse when we talk. Of virtually any conversation, you can say what it is 'about'. |
| 22235 | Feelings are not unchanging, but have a history (especially if they are noble) [Foucault] |
| Full Idea: We believe that feelings are immutable, but every sentiment, particularly the most noble and disinterested, has a history. | |
| From: Michel Foucault (Nietzsche, Genealogy, History [1971], p.86), quoted by Johanna Oksala - How to Read Foucault 5 | |
| A reaction: This is the sort of remark that makes me think Foucault is worth reading. Aristotle thought you could teach correct feelings. That implies that you can also teach incorrect feelings. |