59 ideas
22864 | Philosophy is the study and criticsm of cultural beliefs, to achieve new possibilities [Dewey] |
15945 | Second-order set theory just adds a version of Replacement that quantifies over functions [Lavine] |
15914 | An 'upper bound' is the greatest member of a subset; there may be several of these, so there is a 'least' one [Lavine] |
15921 | Collections of things can't be too big, but collections by a rule seem unlimited in size [Lavine] |
15937 | Those who reject infinite collections also want to reject the Axiom of Choice [Lavine] |
15936 | The Power Set is just the collection of functions from one collection to another [Lavine] |
15899 | Replacement was immediately accepted, despite having very few implications [Lavine] |
15930 | Foundation says descending chains are of finite length, blocking circularity, or ungrounded sets [Lavine] |
15920 | Pure collections of things obey Choice, but collections defined by a rule may not [Lavine] |
15898 | The controversy was not about the Axiom of Choice, but about functions as arbitrary, or given by rules [Lavine] |
15919 | The 'logical' notion of class has some kind of definition or rule to characterise the class [Lavine] |
15900 | The iterative conception of set wasn't suggested until 1947 [Lavine] |
15931 | The iterative conception needs the Axiom of Infinity, to show how far we can iterate [Lavine] |
15932 | The iterative conception doesn't unify the axioms, and has had little impact on mathematical proofs [Lavine] |
15933 | Limitation of Size: if it's the same size as a set, it's a set; it uses Replacement [Lavine] |
15913 | A collection is 'well-ordered' if there is a least element, and all of its successors can be identified [Lavine] |
22873 | Liberalism should improve the system, and not just ameliorate it [Dewey] |
15926 | Second-order logic presupposes a set of relations already fixed by the first-order domain [Lavine] |
15934 | Mathematical proof by contradiction needs the law of excluded middle [Lavine] |
15907 | Mathematics is nowadays (thanks to set theory) regarded as the study of structure, not of quantity [Lavine] |
15942 | Every rational number, unlike every natural number, is divisible by some other number [Lavine] |
15922 | For the real numbers to form a set, we need the Continuum Hypothesis to be true [Lavine] |
18250 | Cauchy gave a necessary condition for the convergence of a sequence [Lavine] |
15904 | The two sides of the Cut are, roughly, the bounding commensurable ratios [Lavine] |
15912 | Counting results in well-ordering, and well-ordering makes counting possible [Lavine] |
15949 | The theory of infinity must rest on our inability to distinguish between very large sizes [Lavine] |
15947 | The infinite is extrapolation from the experience of indefinitely large size [Lavine] |
15940 | The intuitionist endorses only the potential infinite [Lavine] |
15909 | 'Aleph-0' is cardinality of the naturals, 'aleph-1' the next cardinal, 'aleph-ω' the ω-th cardinal [Lavine] |
15915 | Ordinals are basic to Cantor's transfinite, to count the sets [Lavine] |
15917 | Paradox: the class of all ordinals is well-ordered, so must have an ordinal as type - giving a bigger ordinal [Lavine] |
15918 | Paradox: there is no largest cardinal, but the class of everything seems to be the largest [Lavine] |
15929 | Set theory will found all of mathematics - except for the notion of proof [Lavine] |
15935 | Modern mathematics works up to isomorphism, and doesn't care what things 'really are' [Lavine] |
15928 | Intuitionism rejects set-theory to found mathematics [Lavine] |
22869 | Knowledge is either the product of competent enquiry, or it is meaningless [Dewey] |
22868 | The value and truth of knowledge are measured by success in activity [Dewey] |
21516 | We want certainty in order achieve secure results for action [Dewey] |
22867 | The quest for certainty aims for peace, and avoidance of the stress of action [Dewey] |
22870 | No belief can be so settled that it is not subject to further inquiry [Dewey] |
22866 | Mind is never isolated, but only exists in its interactions [Dewey] |
22865 | Habits constitute the self [Dewey] |
8478 | Dewey argued long before Wittgenstein that there could not seriously be a private language [Dewey, by Orenstein] |
22717 | Self-interest can fairly divide a cake; first person cuts, second person chooses [Poundstone] |
22718 | Formal game theory is about maximising or minimising numbers in tables [Poundstone] |
22719 | The minimax theorem says a perfect game of opposed people always has a rational solution [Poundstone] |
22720 | Two prisoners get the best result by being loyal, not by selfish betrayal [Poundstone] |
22721 | The tragedy in prisoner's dilemma is when two 'nice' players misread each other [Poundstone] |
22722 | TIT FOR TAT says cooperate at first, then do what the other player does [Poundstone] |
22723 | Do unto others as you would have them do unto you - or else! [Poundstone] |
22871 | The good people are those who improve; the bad are those who deteriorate [Dewey] |
22876 | Democracy is the development of human nature when it shares in the running of communal activities [Dewey] |
22875 | Democracy is not just a form of government; it is a mode of shared living [Dewey] |
22872 | Liberals aim to allow individuals to realise their capacities [Dewey] |
22874 | Individuality is only developed within groups [Dewey] |
22880 | The things in civilisation we prize are the products of other members of our community [Dewey] |
22879 | 'God' is an imaginative unity of ideal values [Dewey] |
22877 | We should try attaching the intensity of religious devotion to intelligent social action [Dewey] |
22878 | Religions are so shockingly diverse that they have no common element [Dewey] |