26 ideas
| 14249 | Boolos reinterprets second-order logic as plural logic [Boolos, by Oliver/Smiley] |
| 10830 | Second-order logic metatheory is set-theoretic, and second-order validity has set-theoretic problems [Boolos] |
| 10829 | A sentence can't be a truth of logic if it asserts the existence of certain sets [Boolos] |
| 10832 | '∀x x=x' only means 'everything is identical to itself' if the range of 'everything' is fixed [Boolos] |
| 10834 | Weak completeness: if it is valid, it is provable. Strong: it is provable from a set of sentences [Boolos] |
| 13841 | Why should compactness be definitive of logic? [Boolos, by Hacking] |
| 10833 | Many concepts can only be expressed by second-order logic [Boolos] |
| 17536 | If it can't be expressed mathematically, it can't occur in nature? [Heisenberg] |
| 17545 | Quantum theory shows that exact science does not need dogmatic realism [Heisenberg] |
| 17538 | Quantum theory does not introduce minds into atomic events [Heisenberg] |
| 17534 | A 'probability wave' is a quantitative version of Aristotle's potential, a mid-way type of reality [Heisenberg] |
| 17553 | We can retain the idea of 'substance', as indestructible mass or energy [Heisenberg] |
| 17544 | Basic particles have a mathematical form, which is more important than their substance [Heisenberg] |
| 579 | Cratylus said you couldn't even step into the same river once [Cratylus, by Aristotle] |
| 578 | Cratylus decided speech was hopeless, and his only expression was the movement of a finger [Cratylus, by Aristotle] |
| 17550 | We give a mathematical account of a system of natural connections in order to clarify them [Heisenberg] |
| 17549 | Seven theories in science: mechanics, heat, electricity, quantum, particles, relativity, life [Heisenberg, by PG] |
| 17540 | Energy is that which moves, and is the substance from which everything is made [Heisenberg] |
| 17541 | Energy is an unchanging substance, having many forms, and causing all change [Heisenberg] |
| 17548 | Maxwell introduced real fields, which transferred forces from point to point [Heisenberg] |
| 17533 | Radiation interference needs waves, but radiation photoelectric effects needs particles [Heisenberg] |
| 17532 | An atom's stability after collisions needs explaining (which Newton's mechanics can't do) [Heisenberg] |
| 17537 | Position is complementary to velocity or momentum, so the whole system is indeterminate [Heisenberg] |
| 17551 | It was formerly assumed that electromagnetic waves could not be a reality in themselves [Heisenberg] |
| 17543 | So-called 'empty' space is the carrier of geometry and kinematics [Heisenberg] |
| 17552 | In relativity the length of the 'present moment' is relative to distance from the observer [Heisenberg] |