39 ideas
17925 | Showing a disproof is impossible is not a proof, so don't eliminate double negation [Colyvan] |
17926 | Rejecting double negation elimination undermines reductio proofs [Colyvan] |
17924 | Excluded middle says P or not-P; bivalence says P is either true or false [Colyvan] |
17929 | Löwenheim proved his result for a first-order sentence, and Skolem generalised it [Colyvan] |
17930 | Axioms are 'categorical' if all of their models are isomorphic [Colyvan] |
17928 | Ordinal numbers represent order relations [Colyvan] |
17923 | Intuitionists only accept a few safe infinities [Colyvan] |
18200 | Very large sets should be studied in an 'if-then' spirit [Putnam] |
17941 | Infinitesimals were sometimes zero, and sometimes close to zero [Colyvan] |
17922 | Reducing real numbers to rationals suggested arithmetic as the foundation of maths [Colyvan] |
17936 | Transfinite induction moves from all cases, up to the limit ordinal [Colyvan] |
17940 | Most mathematical proofs are using set theory, but without saying so [Colyvan] |
17931 | Structuralism say only 'up to isomorphism' matters because that is all there is to it [Colyvan] |
17932 | If 'in re' structures relies on the world, does the world contain rich enough structures? [Colyvan] |
18199 | Indispensability strongly supports predicative sets, and somewhat supports impredicative sets [Putnam] |
8857 | We must quantify over numbers for science; but that commits us to their existence [Putnam] |
17943 | Probability supports Bayesianism better as degrees of belief than as ratios of frequencies [Colyvan] |
17939 | Mathematics can reveal structural similarities in diverse systems [Colyvan] |
17938 | Mathematics can show why some surprising events have to occur [Colyvan] |
17934 | Proof by cases (by 'exhaustion') is said to be unexplanatory [Colyvan] |
17933 | Reductio proofs do not seem to be very explanatory [Colyvan] |
17935 | If inductive proofs hold because of the structure of natural numbers, they may explain theorems [Colyvan] |
17942 | Can a proof that no one understands (of the four-colour theorem) really be a proof? [Colyvan] |
17937 | Mathematical generalisation is by extending a system, or by abstracting away from it [Colyvan] |
20014 | Actions include: the involuntary, the purposeful, the intentional, and the self-consciously autonomous [Wilson/Schpall] |
20019 | Maybe bodily movements are not actions, but only part of an agent's action of moving [Wilson/Schpall] |
20021 | Is the action the arm movement, the whole causal process, or just the trying to do it? [Wilson/Schpall] |
20022 | To be intentional, an action must succeed in the manner in which it was planned [Wilson/Schpall] |
20023 | If someone believes they can control the lottery, and then wins, the relevant skill is missing [Wilson/Schpall] |
20025 | We might intend two ways to acting, knowing only one of them can succeed [Wilson/Schpall] |
20031 | On one model, an intention is belief-desire states, and intentional actions relate to beliefs and desires [Wilson/Schpall] |
20028 | Groups may act for reasons held by none of the members, so maybe groups are agents [Wilson/Schpall] |
20027 | If there are shared obligations and intentions, we may need a primitive notion of 'joint commitment' [Wilson/Schpall] |
20016 | Strong Cognitivism identifies an intention to act with a belief [Wilson/Schpall] |
20017 | Weak Cognitivism says intentions are only partly constituted by a belief [Wilson/Schpall] |
20018 | Strong Cognitivism implies a mode of 'practical' knowledge, not based on observation [Wilson/Schpall] |
20012 | Maybe the explanation of an action is in the reasons that make it intelligible to the agent [Wilson/Schpall] |
20013 | It is generally assumed that reason explanations are causal [Wilson/Schpall] |
20029 | Causalists allow purposive explanations, but then reduce the purpose to the action's cause [Wilson/Schpall] |