15 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] |
8353 | Freedom involves acting according to an idea [Anscombe] |
8352 | To believe in determinism, one must believe in a system which determines events [Anscombe] |
1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
8351 | With diseases we easily trace a cause from an effect, but we cannot predict effects [Anscombe] |
4777 | The word 'cause' is an abstraction from a group of causal terms in a language (scrape, push..) [Anscombe] |
10363 | Causation is relative to how we describe the primary relata [Anscombe, by Schaffer,J] |
8350 | Since Mill causation has usually been explained by necessary and sufficient conditions [Anscombe] |
5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |