29 ideas
18951 | For scientific purposes there is a precise concept of 'true-in-L', using set theory [Putnam] |
18953 | Modern notation frees us from Aristotle's restriction of only using two class-names in premises [Putnam] |
18949 | The universal syllogism is now expressed as the transitivity of subclasses [Putnam] |
18952 | '⊃' ('if...then') is used with the definition 'Px ⊃ Qx' is short for '¬(Px & ¬Qx)' [Putnam] |
18958 | In type theory, 'x ∈ y' is well defined only if x and y are of the appropriate type [Putnam] |
18954 | Before the late 19th century logic was trivialised by not dealing with relations [Putnam] |
18956 | Asserting first-order validity implicitly involves second-order reference to classes [Putnam] |
18962 | Unfashionably, I think logic has an empirical foundation [Putnam] |
18961 | We can identify functions with certain sets - or identify sets with certain functions [Putnam] |
18955 | Having a valid form doesn't ensure truth, as it may be meaningless [Putnam] |
1507 | We don't have time for infinite quantity, but we do for infinite divisibility, because time is also divisible [Aristotle on Zeno of Elea] |
5109 | The fast runner must always reach the point from which the slower runner started [Zeno of Elea, by Aristotle] |
1512 | Zeno is wrong that one grain of millet makes a sound; why should one grain achieve what the whole bushel does? [Aristotle on Zeno of Elea] |
1508 | Zeno's arrow paradox depends on the assumption that time is composed of nows [Aristotle on Zeno of Elea] |
18959 | Sets larger than the continuum should be studied in an 'if-then' spirit [Putnam] |
17954 | Essence is a thing's necessities, but what about its possibilities (which may not be realised)? [Vetter] |
18957 | Nominalism only makes sense if it is materialist [Putnam] |
18950 | Physics is full of non-physical entities, such as space-vectors [Putnam] |
17953 | Real definition fits abstracta, but not individual concrete objects like Socrates [Vetter] |
17952 | Modal accounts make essence less mysterious, by basing them on the clearer necessity [Vetter] |
17959 | Metaphysical necessity is even more deeply empirical than Kripke has argued [Vetter] |
17955 | Possible worlds allow us to talk about degrees of possibility [Vetter] |
17957 | Maybe possibility is constituted by potentiality [Vetter] |
17958 | The apparently metaphysically possible may only be epistemically possible [Vetter] |
17956 | Closeness of worlds should be determined by the intrinsic nature of relevant objects [Vetter] |
18960 | Most predictions are uninteresting, and are only sought in order to confirm a theory [Putnam] |
454 | If there are many things they must have a finite number, but there must be endless things between them [Zeno of Elea] |
455 | That which moves, moves neither in the place in which it is, nor in that in which it is not [Zeno of Elea] |
1511 | If everything is in a place, what is the place in? Place doesn't exist [Zeno of Elea, by Simplicius] |