68 ideas
3593 | The only way to specify the corresponding fact is asserting the sentence [Williams,M] |
3585 | Coherence needs positive links, not just absence of conflict [Williams,M] |
3584 | Justification needs coherence, while truth might be ideal coherence [Williams,M] |
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] |
3599 | Deduction shows entailments, not what to believe [Williams,M] |
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] |
12887 | A whole must have one characteristic, an internal relation, and a structure [Rescher/Oppenheim] |
3591 | We could never pin down how many beliefs we have [Williams,M] |
3582 | Propositions make error possible, so basic experiential knowledge is impossible [Williams,M] |
3592 | Phenomenalism is a form of idealism [Williams,M] |
3579 | Sense data avoid the danger of misrepresenting the world [Williams,M] |
3581 | Sense data can't give us knowledge if they are non-propositional [Williams,M] |
3564 | Is it people who are justified, or propositions? [Williams,M] |
8851 | Coherentists say that regress problems are assuming 'linear' justification [Williams,M] |
3595 | What works always takes precedence over theories [Williams,M] |
8849 | Traditional foundationalism is radically internalist [Williams,M] |
3580 | Experience must be meaningful to act as foundations [Williams,M] |
8853 | Basic judgements are immune from error because they have no content [Williams,M] |
3578 | Are empirical foundations judgements or experiences? [Williams,M] |
8855 | Sensory experience may be fixed, but it can still be misdescribed [Williams,M] |
3576 | Foundationalists are torn between adequacy and security [Williams,M] |
3577 | Strong justification eliminates error, but also reduces our true beliefs [Williams,M] |
3589 | Why should diverse parts of our knowledge be connected? [Williams,M] |
3590 | Coherence theory must give a foundational status to coherence itself [Williams,M] |
3571 | Externalism does not require knowing that you know [Williams,M] |
3574 | Externalism ignores the social aspect of knowledge [Williams,M] |
3569 | In the causal theory of knowledge the facts must cause the belief [Williams,M] |
3567 | How could there be causal relations to mathematical facts? [Williams,M] |
3586 | Only a belief can justify a belief [Williams,M] |
3573 | Externalist reliability refers to a range of conventional conditions [Williams,M] |
3565 | Sometimes I ought to distrust sources which are actually reliable [Williams,M] |
3566 | We control our beliefs by virtue of how we enquire [Williams,M] |
8852 | In the context of scepticism, externalism does not seem to be an option [Williams,M] |
3594 | Scepticism just reveals our limited ability to explain things [Williams,M] |
3575 | Scepticism can involve discrepancy, relativity, infinity, assumption and circularity [Williams,M] |
3587 | Seeing electrons in a cloud chamber requires theory [Williams,M] |
3588 | Foundationalists base meaning in words, coherentists base it in sentences [Williams,M] |