12 ideas
16541 | All the intrinsic properties of a thing should be deducible from its definition [Spinoza] |
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] |
13073 | To understand the properties we must know the essence, as with a circle [Spinoza] |
7518 | If folk psychology gives a network of causal laws, that fits neatly with functionalism [Churchland,PM] |
7519 | Many mental phenomena are totally unexplained by folk psychology [Churchland,PM] |
7520 | Folk psychology never makes any progress, and is marginalised by modern science [Churchland,PM] |