70 ideas
12926 | Wisdom is the science of happiness [Leibniz] |
12903 | Wise people have fewer acts of will, because such acts are linked together [Leibniz] |
12914 | Metaphysics is geometrical, resting on non-contradiction and sufficient reason [Leibniz] |
12915 | Definitions can only be real if the item is possible [Leibniz] |
19333 | A truth is just a proposition in which the predicate is contained within the subject [Leibniz] |
12910 | The predicate is in the subject of a true proposition [Leibniz] |
9542 | The best known axiomatization of PL is Whitehead/Russell, with four axioms and two rules [Russell/Whitehead, by Hughes/Cresswell] |
21720 | Russell saw Reducibility as legitimate for reducing classes to logic [Linsky,B on Russell/Whitehead] |
10044 | Russell denies extensional sets, because the null can't be a collection, and the singleton is just its element [Russell/Whitehead, by Shapiro] |
18208 | We regard classes as mere symbolic or linguistic conveniences [Russell/Whitehead] |
8204 | Lewis's 'strict implication' preserved Russell's confusion of 'if...then' with implication [Quine on Russell/Whitehead] |
9359 | Russell's implication means that random sentences imply one another [Lewis,CI on Russell/Whitehead] |
21707 | Russell unusually saw logic as 'interpreted' (though very general, and neutral) [Russell/Whitehead, by Linsky,B] |
10036 | In 'Principia' a new abstract theory of relations appeared, and was applied [Russell/Whitehead, by Gödel] |
18248 | A real number is the class of rationals less than the number [Russell/Whitehead, by Shapiro] |
12920 | There is no multiplicity without true units [Leibniz] |
18152 | Russell takes numbers to be classes, but then reduces the classes to numerical quantifiers [Russell/Whitehead, by Bostock] |
8683 | Russell and Whitehead were not realists, but embraced nearly all of maths in logic [Russell/Whitehead, by Friend] |
10025 | Russell and Whitehead took arithmetic to be higher-order logic [Russell/Whitehead, by Hodes] |
10037 | 'Principia' lacks a precise statement of the syntax [Gödel on Russell/Whitehead] |
10093 | The ramified theory of types used propositional functions, and covered bound variables [Russell/Whitehead, by George/Velleman] |
8691 | The Russell/Whitehead type theory was limited, and was not really logic [Friend on Russell/Whitehead] |
10305 | In 'Principia Mathematica', logic is exceeded in the axioms of infinity and reducibility, and in the domains [Bernays on Russell/Whitehead] |
8684 | Russell and Whitehead consider the paradoxes to indicate that we create mathematical reality [Russell/Whitehead, by Friend] |
8746 | To avoid vicious circularity Russell produced ramified type theory, but Ramsey simplified it [Russell/Whitehead, by Shapiro] |
12319 | What is not truly one being is not truly a being either [Leibniz] |
12922 | A thing 'expresses' another if they have a constant and fixed relationship [Leibniz] |
13079 | A substance contains the laws of its operations, and its actions come from its own depth [Leibniz] |
12745 | Philosophy needs the precision of the unity given by substances [Leibniz] |
12921 | Accidental unity has degrees, from a mob to a society to a machine or organism [Leibniz] |
12746 | We find unity in reason, and unity in perception, but these are not true unity [Leibniz] |
12916 | A body is a unified aggregate, unless it has an indivisible substance [Leibniz] |
12919 | Unity needs an indestructible substance, to contain everything which will happen to it [Leibniz] |
12923 | Every bodily substance must have a soul, or something analogous to a soul [Leibniz] |
12704 | Aggregates don’t reduce to points, or atoms, or illusion, so must reduce to substance [Leibniz] |
13077 | Basic predicates give the complete concept, which then predicts all of the actions [Leibniz] |
12908 | Essences exist in the divine understanding [Leibniz] |
12706 | Bodies need a soul (or something like it) to avoid being mere phenomena [Leibniz] |
12906 | Truths about species are eternal or necessary, but individual truths concern what exists [Leibniz] |
12033 | An object is identical with itself, and no different indiscernible object can share that [Russell/Whitehead, by Adams,RM] |
12904 | If varieties of myself can be conceived of as distinct from me, then they are not me [Leibniz] |
11981 | If someone's life went differently, then that would be another individual [Leibniz] |
12905 | I cannot think my non-existence, nor exist without being myself [Leibniz] |
19334 | I can't just know myself to be a substance; I must distinguish myself from others, which is hard [Leibniz] |
10040 | Russell showed, through the paradoxes, that our basic logical intuitions are self-contradictory [Russell/Whitehead, by Gödel] |
5033 | Nothing should be taken as certain without foundations [Leibniz] |
12913 | Nature is explained by mathematics and mechanism, but the laws rest on metaphysics [Leibniz] |
13089 | To fully conceive the subject is to explain the resulting predicates and events [Leibniz] |
5034 | Mind is a thinking substance which can know God and eternal truths [Leibniz] |
5032 | It seems probable that animals have souls, but not consciousness [Leibniz] |
5031 | Everything which happens is not necessary, but is certain after God chooses this universe [Leibniz] |
21725 | The multiple relations theory says assertions about propositions are about their ingredients [Russell/Whitehead, by Linsky,B] |
23474 | A judgement is a complex entity, of mind and various objects [Russell/Whitehead] |
23455 | The meaning of 'Socrates is human' is completed by a judgement [Russell/Whitehead] |
23480 | The multiple relation theory of judgement couldn't explain the unity of sentences [Morris,M on Russell/Whitehead] |
18275 | Only the act of judging completes the meaning of a statement [Russell/Whitehead] |
12911 | Concepts are what unite a proposition [Leibniz] |
23453 | Propositions as objects of judgement don't exist, because we judge several objects, not one [Russell/Whitehead] |
12925 | Beauty increases with familiarity [Leibniz] |
12927 | Happiness is advancement towards perfection [Leibniz] |
13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
15955 | I think the corpuscular theory, rather than forms or qualities, best explains particular phenomena [Leibniz] |
12907 | Each possible world contains its own laws, reflected in the possible individuals of that world [Leibniz] |
12924 | Motion alone is relative, but force is real, and establishes its subject [Leibniz] |
20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |
12909 | Everything, even miracles, belongs to order [Leibniz] |
5030 | Miracles are extraordinary operations by God, but are nevertheless part of his design [Leibniz] |
12912 | Immortality without memory is useless [Leibniz] |
12917 | The soul is indestructible and always self-aware [Leibniz] |
12918 | Animals have souls, but lack consciousness [Leibniz] |