66 ideas
12274 | Begin examination with basics, and subdivide till you can go no further [Aristotle] |
12260 | Dialectic starts from generally accepted opinions [Aristotle] |
12291 | There can't be one definition of two things, or two definitions of the same thing [Aristotle] |
12292 | Definitions are easily destroyed, since they can contain very many assertions [Aristotle] |
17774 | Definitions make our intuitions mathematically useful [Mayberry] |
12283 | In definitions the first term to be assigned ought to be the genus [Aristotle] |
12272 | We describe the essence of a particular thing by means of its differentiae [Aristotle] |
12279 | The differentia indicate the qualities, but not the essence [Aristotle] |
12289 | The genera and the differentiae are part of the essence [Aristotle] |
12261 | Differentia are generic, and belong with genus [Aristotle] |
12263 | 'Genus' is part of the essence shared among several things [Aristotle] |
12285 | The definition is peculiar to one thing, not common to many [Aristotle] |
17773 | Proof shows that it is true, but also why it must be true [Mayberry] |
17796 | There is a semi-categorical axiomatisation of set-theory [Mayberry] |
17795 | Set theory can't be axiomatic, because it is needed to express the very notion of axiomatisation [Mayberry] |
17800 | The misnamed Axiom of Infinity says the natural numbers are finite in size [Mayberry] |
17801 | The set hierarchy doesn't rely on the dubious notion of 'generating' them [Mayberry] |
17803 | Limitation of size is part of the very conception of a set [Mayberry] |
17786 | The mainstream of modern logic sees it as a branch of mathematics [Mayberry] |
17788 | First-order logic only has its main theorems because it is so weak [Mayberry] |
17791 | Only second-order logic can capture mathematical structure up to isomorphism [Mayberry] |
17787 | Big logic has one fixed domain, but standard logic has a domain for each interpretation [Mayberry] |
17790 | No Löwenheim-Skolem logic can axiomatise real analysis [Mayberry] |
17779 | 'Classificatory' axioms aim at revealing similarity in morphology of structures [Mayberry] |
17778 | Axiomatiation relies on isomorphic structures being essentially the same [Mayberry] |
17780 | 'Eliminatory' axioms get rid of traditional ideal and abstract objects [Mayberry] |
17789 | No logic which can axiomatise arithmetic can be compact or complete [Mayberry] |
11261 | Puzzles arise when reasoning seems equal on both sides [Aristotle] |
17784 | Real numbers can be eliminated, by axiom systems for complete ordered fields [Mayberry] |
12273 | Unit is the starting point of number [Aristotle] |
17782 | Greek quantities were concrete, and ratio and proportion were their science [Mayberry] |
17781 | Real numbers were invented, as objects, to simplify and generalise 'quantity' [Mayberry] |
17799 | Cantor's infinite is an absolute, of all the sets or all the ordinal numbers [Mayberry] |
17797 | Cantor extended the finite (rather than 'taming the infinite') [Mayberry] |
17775 | If proof and definition are central, then mathematics needs and possesses foundations [Mayberry] |
17776 | The ultimate principles and concepts of mathematics are presumed, or grasped directly [Mayberry] |
17777 | Foundations need concepts, definition rules, premises, and proof rules [Mayberry] |
17804 | Axiom theories can't give foundations for mathematics - that's using axioms to explain axioms [Mayberry] |
17792 | 1st-order PA is only interesting because of results which use 2nd-order PA [Mayberry] |
17793 | It is only 2nd-order isomorphism which suggested first-order PA completeness [Mayberry] |
17794 | Set theory is not just first-order ZF, because that is inadequate for mathematics [Mayberry] |
17802 | We don't translate mathematics into set theory, because it comes embodied in that way [Mayberry] |
17805 | Set theory is not just another axiomatised part of mathematics [Mayberry] |
12267 | There are ten categories: essence, quantity, quality, relation, place, time, position, state, activity, passivity [Aristotle] |
12282 | An individual property has to exist (in past, present or future) [Aristotle] |
12264 | An 'accident' is something which may possibly either belong or not belong to a thing [Aristotle] |
17785 | Real numbers as abstracted objects are now treated as complete ordered fields [Mayberry] |
12280 | Genus gives the essence better than the differentiae do [Aristotle] |
13269 | In the case of a house the parts can exist without the whole, so parts are not the whole [Aristotle] |
12284 | Everything that is has one single essence [Aristotle] |
12262 | An 'idion' belongs uniquely to a thing, but is not part of its essence [Aristotle] |
12290 | Destruction is dissolution of essence [Aristotle] |
12286 | If two things are the same, they must have the same source and origin [Aristotle] |
12266 | 'Same' is mainly for names or definitions, but also for propria, and for accidents [Aristotle] |
12287 | Two identical things have the same accidents, they are the same; if the accidents differ, they're different [Aristotle] |
12288 | Numerical sameness and generic sameness are not the same [Aristotle] |
12259 | Reasoning is when some results follow necessarily from certain claims [Aristotle] |
12271 | Induction is the progress from particulars to universals [Aristotle] |
12293 | We say 'so in cases of this kind', but how do you decide what is 'of this kind'? [Aristotle] |
7517 | I could take a healthy infant and train it up to be any type of specialist I choose [Watson,JB] |
12276 | Justice and self-control are better than courage, because they are always useful [Aristotle] |
12277 | Friendship is preferable to money, since its excess is preferable [Aristotle] |
12275 | We value friendship just for its own sake [Aristotle] |
12281 | Man is intrinsically a civilized animal [Aristotle] |
12265 | All water is the same, because of a certain similarity [Aristotle] |
12278 | 'Being' and 'oneness' are predicated of everything which exists [Aristotle] |