9 ideas
19389 | Truth is a characteristic of possible thoughts [Leibniz] |
19388 | True and false seem to pertain to thoughts, yet unthought propositions seem to be true or false [Leibniz] |
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] |
10067 | Gentzen proved the consistency of arithmetic from assumptions beyond arithmetic [Gentzen, by Musgrave] |
7458 | The reliability of witnesses depends on whether they benefit from their observations [Laplace, by Hacking] |
3441 | If a supreme intellect knew all atoms and movements, it could know all of the past and the future [Laplace] |