4 ideas
18758 | Validity is provable, but invalidity isn't, because the model is infinite [Church, by McGee] |
22363 | You have only begun to do real science when you can express it in numbers [Kelvin] |
19216 | Propositions (such as 'that dog is barking') only exist if their items exist [Williamson] |
20644 | Energy has progressed from a mere formula, to a principle pervading all nature [Kelvin] |