79 ideas
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] |
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] |
4098 | The theory of descriptions supports internalism, since they are thinkable when the object is non-existent [Crane] |
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] |
4077 | Aesthetic properties of thing supervene on their physical properties [Crane] |
4078 | Constitution (as in a statue constituted by its marble) is supervenience without identity [Crane] |
8386 | Events are picked out by descriptions, and facts by whole sentences [Crane] |
4082 | The distinction between 'resultant' properties (weight) and 'emergent' properties is a bit vague [Crane] |
4083 | If mental properties are emergent they add a new type of causation, and physics is not complete [Crane] |
4079 | Properties are causes [Crane] |
4068 | Traditional substance is separate from properties and capable of independent existence [Crane] |
4096 | Maybe beliefs don't need to be conscious, if you are not conscious of the beliefs guiding your actions [Crane] |
4097 | Maybe there are two kinds of belief - 'de re' beliefs and 'de dicto' beliefs [Crane] |
4093 | Many cases of knowing how can be expressed in propositional terms (like how to get somewhere) [Crane] |
4108 | Phenol-thio-urea tastes bitter to three-quarters of people, but to the rest it is tasteless, so which is it? [Crane] |
4105 | The traditional supports for the sense datum theory were seeing double and specks before one's eyes [Crane] |
4104 | One can taste that the wine is sour, and one can also taste the sourness of the wine [Crane] |
4101 | If we smell something we are aware of the smell separately, but we don't perceive a 'look' when we see [Crane] |
4102 | The problems of perception disappear if it is a relation to an intentional state, not to an object or sense datum [Crane] |
4109 | If perception is much richer than our powers of description, this suggests that it is non-conceptual [Crane] |
4103 | The adverbial theory of perceptions says it is the experiences which have properties, not the objects [Crane] |
4065 | Is knowledge just a state of mind, or does it also involve the existence of external things? [Crane] |
4092 | The core of the consciousness problem is the case of Mary, zombies, and the Hard Question [Crane] |
4087 | Intentionalism does not require that all mental states be propositional attitudes [Crane] |
4095 | Object-directed attitudes like love are just as significant as propositional attitudes [Crane] |
4106 | If someone removes their glasses the content of experience remains, but the quality changes [Crane] |
4089 | Pains have a region of the body as their intentional content, not some pain object [Crane] |
4090 | Weak intentionalism says qualia are extra properties; strong intentionalism says they are intentional [Crane] |
4107 | With inverted qualia a person's experiences would change, but their beliefs remain the same [Crane] |
4069 | Descartes did not think of minds as made of a substance, because they are not divisible [Crane] |
4074 | Functionalism defines mental states by their causal properties, which rules out epiphenomenalism [Crane] |
4091 | The problems of misrepresentation and error have dogged physicalist reductions of intentionality [Crane] |
4070 | Properties dualism says mental properties are distinct from physical, despite a single underlying substance [Crane] |
4084 | Non-reductive physicalism seeks an explanation of supervenience, but emergentists accept it as basic [Crane] |
4080 | If mental supervenes on the physical, then every physical cause will be accompanied by a mental one [Crane] |
4075 | Identity theory is either of particular events, or of properties, depending on your theory of causation [Crane] |
4085 | Physicalism may be the source of the mind-body problem, rather than its solution [Crane] |
4073 | Overdetermination occurs if two events cause an effect, when each would have caused it alone [Crane] |
4072 | The completeness of physics must be an essential component of any physicalist view of mind [Crane] |
4094 | Experience teaches us propositions, because we can reason about our phenomenal experience [Crane] |
4100 | The Twin Earth argument depends on reference being determined by content, which may be false. [Crane] |
4067 | Broad content entails the existence of the object of the thought [Crane] |
4063 | In intensional contexts, truth depends on how extensions are conceived. [Crane] |
20239 | Unlike us, the early Greeks thought envy was a good thing, and hope a bad thing [Hesiod, by Nietzsche] |
4071 | Causation can be seen in counterfactual terms, or as increased probability, or as energy flow [Crane] |
8387 | A cause has its effects in virtue of its properties [Crane] |
4076 | Causes are properties, not events, because properties are what make a difference in a situation [Crane] |
8384 | The regularity theory explains a causal event by other items than the two that are involved [Crane] |
4066 | It seems that 'exists' could sometimes be a predicate [Crane] |