4 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] |
8728 | Intuitionist mathematics deduces by introspective construction, and rejects unknown truths [Brouwer] |
19399 | Prime matter is nothing when it is at rest [Leibniz] |