14 ideas
| 16000 | Fixed ideas should be tackled aggressively [Kierkegaard] |
| 16012 | Philosophy can't be unbiased if it ignores language, as that is no more independent than individuals are [Kierkegaard] |
| 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] |
| 16003 | If people marry just because they are lonely, that is self-love, not love [Kierkegaard] |
| 21910 | Our destiny is the highest pitch of world-weariness [Kierkegaard] |
| 16001 | Life may be understood backwards, but it has to be lived forwards [Kierkegaard] |
| 16008 | The best way to be a Christian is without 'Christianity' [Kierkegaard] |
| 20735 | We need to see that Christianity cannot be understood [Kierkegaard] |
| 16713 | Philosophers are the forefathers of heretics [Tertullian] |
| 6610 | I believe because it is absurd [Tertullian] |