40 ideas
23728 | Analysis aims to express the full set of platitudes surrounding a given concept [Smith,M] |
23744 | Defining a set of things by paradigms doesn't pin them down enough [Smith,M] |
10888 | Sets can be defined by 'enumeration', or by 'abstraction' (based on a property) [Zalabardo] |
10889 | The 'Cartesian Product' of two sets relates them by pairing every element with every element [Zalabardo] |
10890 | A 'partial ordering' is reflexive, antisymmetric and transitive [Zalabardo] |
10886 | Determinacy: an object is either in a set, or it isn't [Zalabardo] |
10887 | Specification: Determinate totals of objects always make a set [Zalabardo] |
10897 | A first-order 'sentence' is a formula with no free variables [Zalabardo] |
10893 | Γ |= φ for sentences if φ is true when all of Γ is true [Zalabardo] |
10899 | Γ |= φ if φ is true when all of Γ is true, for all structures and interpretations [Zalabardo] |
10896 | Propositional logic just needs ¬, and one of ∧, ∨ and → [Zalabardo] |
10898 | The semantics shows how truth values depend on instantiations of properties and relations [Zalabardo] |
10902 | We can do semantics by looking at given propositions, or by building new ones [Zalabardo] |
10892 | We make a truth assignment to T and F, which may be true and false, but merely differ from one another [Zalabardo] |
10895 | 'Logically true' (|= φ) is true for every truth-assignment [Zalabardo] |
10900 | Logically true sentences are true in all structures [Zalabardo] |
10894 | A sentence-set is 'satisfiable' if at least one truth-assignment makes them all true [Zalabardo] |
10901 | Some formulas are 'satisfiable' if there is a structure and interpretation that makes them true [Zalabardo] |
10903 | A structure models a sentence if it is true in the model, and a set of sentences if they are all true in the model [Zalabardo] |
10891 | If a set is defined by induction, then proof by induction can be applied to it [Zalabardo] |
23743 | Capturing all the common sense facts about rationality is almost impossible [Smith,M] |
23739 | Goals need desires, and so only desires can motivate us [Smith,M] |
23724 | A pure desire could be criticised if it were based on a false belief [Smith,M] |
23736 | A person can have a desire without feeling it [Smith,M] |
23723 | In the Humean account, desires are not true/false, or subject to any rational criticism [Smith,M] |
23735 | Subjects may be fallible about the desires which explain their actions [Smith,M] |
23738 | Humeans (unlike their opponents) say that desires and judgements can separate [Smith,M] |
23742 | If first- and second-order desires conflict, harmony does not require the second-order to win [Smith,M] |
23746 | Objective reasons to act might be the systematic desires of a fully rational person [Smith,M] |
23733 | Motivating reasons are psychological, while normative reasons are external [Smith,M] |
23740 | Humeans take maximising desire satisfaction as the normative reasons for actions [Smith,M] |
23745 | We cannot expect even fully rational people to converge on having the same desires for action [Smith,M] |
23731 | 'Externalists' say moral judgements are not reasons, and maybe not even motives [Smith,M] |
23732 | A person could make a moral judgement without being in any way motivated by it [Smith,M] |
23729 | Moral internalism says a judgement of rightness is thereby motivating [Smith,M] |
23730 | 'Rationalism' says the rightness of an action is a reason to perform it [Smith,M] |
23727 | Expressivists count attitudes as 'moral' if they concern features of things, rather than their mere existence [Smith,M] |
23741 | Is valuing something a matter of believing or a matter of desiring? [Smith,M] |
13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |