21 ideas
11103 | We aren't stuck with our native conceptual scheme; we can gradually change it [Quine] |
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] |
11092 | A river is a process, with stages; if we consider it as one thing, we are considering a process [Quine] |
11093 | We don't say 'red' is abstract, unlike a river, just because it has discontinuous shape [Quine] |
11101 | General terms don't commit us ontologically, but singular terms with substitution do [Quine] |
11096 | Discourse generally departmentalizes itself to some degree [Quine] |
11099 | Understanding 'is square' is knowing when to apply it, not knowing some object [Quine] |
11094 | 'Red' is a single concrete object in space-time; 'red' and 'drop' are parts of a red drop [Quine] |
11097 | Red is the largest red thing in the universe [Quine] |
17595 | To unite a sequence of ostensions to make one object, a prior concept of identity is needed [Quine] |
11095 | We should just identify any items which are indiscernible within a given discourse [Quine] |
11104 | Concepts are language [Quine] |
11102 | Apply '-ness' or 'class of' to abstract general terms, to get second-level abstract singular terms [Quine] |
1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |