13 ideas
| 19336 | Wisdom involves the desire to achieve perfection [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] |
| 7696 | Leibniz first asked 'why is there something rather than nothing?' [Leibniz, by Jacquette] |
| 19341 | There must be a straining towards existence in the essence of all possible things [Leibniz] |
| 19428 | Because something does exist, there must be a drive in possible things towards existence [Leibniz] |
| 5047 | The world is physically necessary, as its contrary would imply imperfection or moral absurdity [Leibniz] |
| 19343 | We follow the practical rule which always seeks maximum effect for minimum cost [Leibniz] |
| 7667 | There are two sides to men - the pleasantly social, and the violent and creative [Diderot, by Berlin] |
| 19429 | The principle of determination in things obtains the greatest effect with the least effort [Leibniz] |