14 ideas
11022 | Gentzen introduced a natural deduction calculus (NK) in 1934 [Gentzen, by Read] |
11065 | The inferential role of a logical constant constitutes its meaning [Gentzen, by Hanna] |
11023 | The logical connectives are 'defined' by their introduction rules [Gentzen] |
11213 | Each logical symbol has an 'introduction' rule to define it, and hence an 'elimination' rule [Gentzen] |
13832 | Natural deduction shows the heart of reasoning (and sequent calculus is just a tool) [Gentzen, by Hacking] |
10067 | Gentzen proved the consistency of arithmetic from assumptions beyond arithmetic [Gentzen, by Musgrave] |
579 | Cratylus said you couldn't even step into the same river once [Cratylus, by Aristotle] |
17771 | How we evaluate evidence depends on our background beliefs [Bayne] |
17770 | Clifford's dictum seems to block our beliefs in morality, politics and philosophy [Bayne] |
578 | Cratylus decided speech was hopeless, and his only expression was the movement of a finger [Cratylus, by Aristotle] |
17766 | Physicalism correlates brain and mind, explains causation by thought, and makes nature continuous [Bayne] |
17768 | Perception reveals what animals think, but humans can disengage thought from perception [Bayne] |
17769 | Some people centre space on themselves; others centre space on the earth [Bayne] |
17767 | The alternative to a language of thought is map-like or diagram-like thought [Bayne] |