60 ideas
12027 | There must be a plausible epistemological theory alongside any metaphysical theory [Forbes,G] |
8083 | Boole applied normal algebra to logic, aiming at an algebra of thought [Boole, by Devlin] |
7727 | Boole's notation can represent syllogisms and propositional arguments, but not both at once [Boole, by Weiner] |
12005 | The symbol 'ι' forms definite descriptions; (ιx)F(x) says 'the x which is such that F(x)' [Forbes,G] |
8686 | Boole made logic more mathematical, with algebra, quantifiers and probability [Boole, by Friend] |
12010 | Is the meaning of 'and' given by its truth table, or by its introduction and elimination rules? [Forbes,G] |
22277 | Boole's method was axiomatic, achieving economy, plus multiple interpretations [Boole, by Potter] |
12023 | Vagueness problems arise from applying sharp semantics to vague languages [Forbes,G] |
16661 | There are two sorts of category - referring to things, and to circumstances of things [Boethius] |
15035 | If universals are not separate, we can isolate them by abstraction [Boethius, by Panaccio] |
12017 | In all instances of identity, there must be some facts to ensure the identity [Forbes,G] |
14665 | We can call the quality of Plato 'Platonity', and say it is a quality which only he possesses [Boethius] |
12024 | If we combined two clocks, it seems that two clocks may have become one clock. [Forbes,G] |
11885 | Only individual essences will ground identities across worlds in other properties [Forbes,G, by Mackie,P] |
12014 | An individual essence is a set of essential properties which only that object can have [Forbes,G] |
12015 | Non-trivial individual essence is properties other than de dicto, or universal, or relational [Forbes,G] |
12013 | Essential properties depend on a category, and perhaps also on particular facts [Forbes,G] |
13804 | A property is essential iff the object would not exist if it lacked that property [Forbes,G] |
13805 | Properties are trivially essential if they are not grounded in a thing's specific nature [Forbes,G] |
12012 | Essential properties are those without which an object could not exist [Forbes,G] |
13808 | A relation is essential to two items if it holds in every world where they exist [Forbes,G] |
13806 | Trivially essential properties are existence, self-identity, and de dicto necessities [Forbes,G] |
13807 | A property is 'extraneously essential' if it is had only because of the properties of other objects [Forbes,G] |
12025 | Artefacts have fuzzy essences [Forbes,G] |
12022 | Same parts does not ensure same artefact, if those parts could constitute a different artefact [Forbes,G] |
13809 | One might be essentialist about the original bronze from which a statue was made [Forbes,G] |
12020 | An individual might change their sex in a world, but couldn't have differed in sex at origin [Forbes,G] |
11888 | Identities must hold because of other facts, which must be instrinsic [Forbes,G, by Mackie,P] |
12003 | De re modal formulae, unlike de dicto, are sensitive to transworld identities [Forbes,G] |
12028 | De re necessity is a form of conceptual necessity, just as de dicto necessity is [Forbes,G] |
13810 | The source of de dicto necessity is not concepts, but the actual properties of the thing [Forbes,G] |
12008 | Unlike places and times, we cannot separate possible worlds from what is true at them [Forbes,G] |
12009 | The problem with possible worlds realism is epistemological; we can't know properties of possible objects [Forbes,G] |
12007 | Possible worlds are points of logical space, rather like other times than our own [Forbes,G] |
12011 | Transworld identity concerns the limits of possibility for ordinary things [Forbes,G] |
12016 | The problem of transworld identity can be solved by individual essences [Forbes,G] |
12004 | Counterpart theory is not good at handling the logic of identity [Forbes,G] |
12021 | Haecceitism attributes to each individual a primitive identity or thisness [Forbes,G] |
12029 | We believe in thisnesses, because we reject bizarre possibilities as not being about that individual [Forbes,G] |
23308 | Reasoning relates to understanding as time does to eternity [Boethius, by Sorabji] |
5771 | Knowledge of present events doesn't make them necessary, so future events are no different [Boethius] |
5767 | Rational natures require free will, in order to have power of judgement [Boethius] |
5769 | Does foreknowledge cause necessity, or necessity cause foreknowledge? [Boethius] |
5768 | God's universal foreknowledge seems opposed to free will [Boethius] |
5762 | The wicked want goodness, so they would not be wicked if they obtained it [Boethius] |
5770 | Rewards and punishments are not deserved if they don't arise from free movement of the mind [Boethius] |
5764 | When people fall into wickedness they lose their human nature [Boethius] |
5756 | Happiness is a good which once obtained leaves nothing more to be desired [Boethius] |
5763 | The bad seek the good through desire, but the good through virtue, which is more natural [Boethius] |
5759 | Varied aims cannot be good because they differ, but only become good when they unify [Boethius] |
5754 | You can't control someone's free mind, only their body and possessions [Boethius] |
16692 | Divine eternity is the all-at-once and complete possession of unending life [Boethius] |
5752 | Where does evil come from if there is a god; where does good come from if there isn't? [Boethius] |
5757 | God is the supreme good, so no source of goodness could take precedence over God [Boethius] |
5758 | God is the good [Boethius] |
5760 | The power through which creation remains in existence and motion I call 'God' [Boethius] |
5753 | The regular events of this life could never be due to chance [Boethius] |
5765 | The reward of the good is to become gods [Boethius] |
5761 | God can do anything, but he cannot do evil, so evil must be nothing [Boethius] |
5766 | If you could see the plan of Providence, you would not think there was evil anywhere [Boethius] |