36 ideas
10859 | A set is 'well-ordered' if every subset has a first element [Clegg] |
10857 | Set theory made a closer study of infinity possible [Clegg] |
10864 | Any set can always generate a larger set - its powerset, of subsets [Clegg] |
10872 | Extensionality: Two sets are equal if and only if they have the same elements [Clegg] |
10875 | Pairing: For any two sets there exists a set to which they both belong [Clegg] |
10876 | Unions: There is a set of all the elements which belong to at least one set in a collection [Clegg] |
10878 | Infinity: There exists a set of the empty set and the successor of each element [Clegg] |
10877 | Powers: All the subsets of a given set form their own new powerset [Clegg] |
10879 | Choice: For every set a mechanism will choose one member of any non-empty subset [Clegg] |
10871 | Axiom of Existence: there exists at least one set [Clegg] |
10874 | Specification: a condition applied to a set will always produce a new set [Clegg] |
10880 | Mathematics can be 'pure' (unapplied), 'real' (physically grounded); or 'applied' (just applicable) [Clegg] |
10861 | Beyond infinity cardinals and ordinals can come apart [Clegg] |
10860 | An ordinal number is defined by the set that comes before it [Clegg] |
10854 | Transcendental numbers can't be fitted to finite equations [Clegg] |
10858 | By adding an axis of imaginary numbers, we get the useful 'number plane' instead of number line [Clegg] |
10853 | Either lack of zero made early mathematics geometrical, or the geometrical approach made zero meaningless [Clegg] |
10866 | Cantor's account of infinities has the shaky foundation of irrational numbers [Clegg] |
10869 | The Continuum Hypothesis is independent of the axioms of set theory [Clegg] |
10862 | The 'continuum hypothesis' says aleph-one is the cardinality of the reals [Clegg] |
8502 | Realism doesn't explain 'a is F' any further by saying it is 'a has F-ness' [Devitt] |
8503 | The particular/universal distinction is unhelpful clutter; we should accept 'a is F' as basic [Devitt] |
8501 | Quineans take predication about objects as basic, not reference to properties they may have [Devitt] |
17368 | Essentialism concerns the nature of a group, not its category [Devitt] |
17370 | Things that gradually change, like species, can still have essences [Devitt] |
9354 | Why should necessities only be knowable a priori? That Hesperus is Phosporus is known empirically [Devitt] |
19565 | How could the mind have a link to the necessary character of reality? [Devitt] |
9353 | We explain away a priori knowledge, not as directly empirical, but as indirectly holistically empirical [Devitt] |
9356 | The idea of the a priori is so obscure that it won't explain anything [Devitt] |
19564 | Some knowledge must be empirical; naturalism implies that all knowledge is like that [Devitt] |
6005 | Animals are dangerous and nourishing, and can't form contracts of justice [Hermarchus, by Sedley] |
17371 | Some kinds are very explanatory, but others less so, and some not at all [Devitt] |
17369 | We name species as small to share properties, but large enough to yield generalisations [Devitt] |
17367 | Species are phenetic, biological, niche, or phylogenetic-cladistic [Devitt, by PG] |
17372 | The higher categories are not natural kinds, so the Linnaean hierarchy should be given up [Devitt] |
17373 | Species pluralism says there are several good accounts of what a species is [Devitt] |