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3 ideas
| 23356 | Self-evidence is most obvious when people who deny a proposition still have to use it [Epictetus] |
| Full Idea: It is about the strongest proof one could offer of a proposition being evident, that even he who contradicts it finds himself having to make use of it. | |
| From: Epictetus (The Discourses [c.56], 2.20.01) | |
| A reaction: Philosophers sometimes make fools of themselves by trying, by the use of elaborate sophistry, to demolish propositions which are self-evidently true. Don't be one of these philosophers! |
| 9344 | Mathematical analysis ends in primitive principles, which cannot be and need not be demonstrated [Leibniz] |
| Full Idea: At the end of the analytical method in mathematics there are simple ideas of which no definition can be given. Moreover there are axioms and postulates, in short, primitive principles, which cannot be demonstrated and do not need demonstration. | |
| From: Gottfried Leibniz (Monadology [1716], §35) | |
| A reaction: My view is that we do not know such principles when we apprehend them in isolation. I would call them 'intuitions'. They only ascend to the status of knowledge when the mathematics is extended and derived from them, and found to work. |
| 2110 | We all expect the sun to rise tomorrow by experience, but astronomers expect it by reason [Leibniz] |
| Full Idea: When we expect it to be day tomorrow, we all behave as empiricists, because until now it has always happened thus. The astronomer alone knows this by reason. | |
| From: Gottfried Leibniz (Monadology [1716], §28) |