20 ideas
10482 | The logic of ZF is classical first-order predicate logic with identity [Boolos] |
10492 | A few axioms of set theory 'force themselves on us', but most of them don't [Boolos] |
10485 | Naïve sets are inconsistent: there is no set for things that do not belong to themselves [Boolos] |
10484 | The iterative conception says sets are formed at stages; some are 'earlier', and must be formed first [Boolos] |
10491 | Infinite natural numbers is as obvious as infinite sentences in English [Boolos] |
10483 | Mathematics and science do not require very high orders of infinity [Boolos] |
10490 | Mathematics isn't surprising, given that we experience many objects as abstract [Boolos] |
10488 | It is lunacy to think we only see ink-marks, and not word-types [Boolos] |
10487 | I am a fan of abstract objects, and confident of their existence [Boolos] |
10489 | We deal with abstract objects all the time: software, poems, mistakes, triangles.. [Boolos] |
8915 | How we refer to abstractions is much less clear than how we refer to other things [Rosen] |
579 | Cratylus said you couldn't even step into the same river once [Cratylus, by Aristotle] |
578 | Cratylus decided speech was hopeless, and his only expression was the movement of a finger [Cratylus, by Aristotle] |
8917 | The Way of Abstraction used to say an abstraction is an idea that was formed by abstracting [Rosen] |
8912 | Nowadays abstractions are defined as non-spatial, causally inert things [Rosen] |
8913 | Chess may be abstract, but it has existed in specific space and time [Rosen] |
8914 | Sets are said to be abstract and non-spatial, but a set of books can be on a shelf [Rosen] |
8916 | Conflating abstractions with either sets or universals is a big claim, needing a big defence [Rosen] |
8918 | Functional terms can pick out abstractions by asserting an equivalence relation [Rosen] |
8919 | Abstraction by equivalence relationships might prove that a train is an abstract entity [Rosen] |