91 ideas
17016 | Philosophy must abstract from the senses [Newton] |
18137 | Impredicative definitions are wrong, because they change the set that is being defined? [Bostock] |
18122 | Classical interdefinitions of logical constants and quantifiers is impossible in intuitionism [Bostock] |
18114 | There is no single agreed structure for set theory [Bostock] |
18107 | A 'proper class' cannot be a member of anything [Bostock] |
18115 | We could add axioms to make sets either as small or as large as possible [Bostock] |
18139 | The Axiom of Choice relies on reference to sets that we are unable to describe [Bostock] |
18105 | Replacement enforces a 'limitation of size' test for the existence of sets [Bostock] |
18108 | First-order logic is not decidable: there is no test of whether any formula is valid [Bostock] |
18109 | The completeness of first-order logic implies its compactness [Bostock] |
18123 | Substitutional quantification is just standard if all objects in the domain have a name [Bostock] |
18120 | The Deduction Theorem is what licenses a system of natural deduction [Bostock] |
18125 | Berry's Paradox considers the meaning of 'The least number not named by this name' [Bostock] |
18079 | Newton developed a kinematic approach to geometry [Newton, by Kitcher] |
18101 | Each addition changes the ordinality but not the cardinality, prior to aleph-1 [Bostock] |
18100 | ω + 1 is a new ordinal, but its cardinality is unchanged [Bostock] |
18102 | A cardinal is the earliest ordinal that has that number of predecessors [Bostock] |
18106 | Aleph-1 is the first ordinal that exceeds aleph-0 [Bostock] |
18095 | Instead of by cuts or series convergence, real numbers could be defined by axioms [Bostock] |
18099 | The number of reals is the number of subsets of the natural numbers [Bostock] |
18093 | For Eudoxus cuts in rationals are unique, but not every cut makes a real number [Bostock] |
18110 | Infinitesimals are not actually contradictory, because they can be non-standard real numbers [Bostock] |
18082 | Quantities and ratios which continually converge will eventually become equal [Newton] |
18156 | Modern axioms of geometry do not need the real numbers [Bostock] |
18097 | The Peano Axioms describe a unique structure [Bostock] |
18148 | Hume's Principle is a definition with existential claims, and won't explain numbers [Bostock] |
18145 | Many things will satisfy Hume's Principle, so there are many interpretations of it [Bostock] |
18149 | There are many criteria for the identity of numbers [Bostock] |
18143 | Frege makes numbers sets to solve the Caesar problem, but maybe Caesar is a set! [Bostock] |
18116 | Numbers can't be positions, if nothing decides what position a given number has [Bostock] |
18117 | Structuralism falsely assumes relations to other numbers are numbers' only properties [Bostock] |
18141 | Nominalism about mathematics is either reductionist, or fictionalist [Bostock] |
18157 | Nominalism as based on application of numbers is no good, because there are too many applications [Bostock] |
18150 | Actual measurement could never require the precision of the real numbers [Bostock] |
18158 | Ordinals are mainly used adjectively, as in 'the first', 'the second'... [Bostock] |
18127 | Simple type theory has 'levels', but ramified type theory has 'orders' [Bostock] |
18144 | Neo-logicists agree that HP introduces number, but also claim that it suffices for the job [Bostock] |
18147 | Neo-logicists meet the Caesar problem by saying Hume's Principle is unique to number [Bostock] |
18146 | If Hume's Principle is the whole story, that implies structuralism [Bostock] |
18129 | Many crucial logicist definitions are in fact impredicative [Bostock] |
18111 | Treating numbers as objects doesn't seem like logic, since arithmetic fixes their totality [Bostock] |
18159 | Higher cardinalities in sets are just fairy stories [Bostock] |
18155 | A fairy tale may give predictions, but only a true theory can give explanations [Bostock] |
18140 | The best version of conceptualism is predicativism [Bostock] |
18138 | Conceptualism fails to grasp mathematical properties, infinity, and objective truth values [Bostock] |
18131 | If abstracta only exist if they are expressible, there can only be denumerably many of them [Bostock] |
18134 | Predicativism makes theories of huge cardinals impossible [Bostock] |
18135 | If mathematics rests on science, predicativism may be the best approach [Bostock] |
18136 | If we can only think of what we can describe, predicativism may be implied [Bostock] |
18132 | The predicativity restriction makes a difference with the real numbers [Bostock] |
18133 | The usual definitions of identity and of natural numbers are impredicative [Bostock] |
17011 | I suspect that each particle of bodies has attractive or repelling forces [Newton] |
17028 | Particles mutually attract, and cohere at short distances [Newton] |
17014 | The place of a thing is the sum of the places of its parts [Newton] |
17546 | If you changed one of Newton's concepts you would destroy his whole system [Heisenberg on Newton] |
17027 | Science deduces propositions from phenomena, and generalises them by induction [Newton] |
17022 | We should admit only enough causes to explain a phenomenon, and no more [Newton] |
17021 | Natural effects of the same kind should be assumed to have the same causes [Newton] |
17026 | From the phenomena, I can't deduce the reason for the properties of gravity [Newton] |
18121 | In logic a proposition means the same when it is and when it is not asserted [Bostock] |
7903 | The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna] |
6421 | Newton's four fundamentals are: space, time, matter and force [Newton, by Russell] |
13470 | Mass is central to matter [Newton, by Hart,WD] |
17020 | An attraction of a body is the sum of the forces of their particles [Newton] |
23012 | Newtonian causation is changes of motion resulting from collisions [Newton, by Baron/Miller] |
17008 | You have discovered that elliptical orbits result just from gravitation and planetary movement [Newton, by Leibniz] |
17010 | We have given up substantial forms, and now aim for mathematical laws [Newton] |
17023 | I am not saying gravity is essential to bodies [Newton] |
15866 | Newton reclassified vertical motion as violent, and unconstrained horizontal motion as natural [Newton, by Harré] |
15958 | Inertia rejects the Aristotelian idea of things having natural states, to which they return [Newton, by Alexander,P] |
17017 | 1: Bodies rest, or move in straight lines, unless acted on by forces [Newton] |
17019 | 3: All actions of bodies have an equal and opposite reaction [Newton] |
20968 | Newton's Third Law implies the conservation of momentum [Newton, by Papineau] |
17018 | 2: Change of motion is proportional to the force [Newton] |
17547 | Newton's idea of force acting over a long distance was very strange [Heisenberg on Newton] |
20966 | Newton introduced forces other than by contact [Newton, by Papineau] |
20967 | Newton's laws cover the effects of forces, but not their causes [Newton, by Papineau] |
16708 | Newton's forces were accused of being the scholastics' real qualities [Pasnau on Newton] |
13153 | I am studying the quantities and mathematics of forces, not their species or qualities [Newton] |
12724 | The aim is to discover forces from motions, and use forces to demonstrate other phenomena [Newton] |
13593 | Newton showed that falling to earth and orbiting the sun are essentially the same [Newton, by Ellis] |
20969 | Early Newtonians could not formulate conservation of energy, having no concept of potential energy [Newton, by Papineau] |
17013 | Absolute space is independent, homogeneous and immovable [Newton] |
22915 | Newton needs intervals of time, to define velocity and acceleration [Newton, by Le Poidevin] |
22893 | Newton thought his laws of motion needed absolute time [Newton, by Bardon] |
17012 | Time exists independently, and flows uniformly [Newton] |
14012 | Absolute time, from its own nature, flows equably, without relation to anything external [Newton] |
22954 | Newtonian mechanics does not distinguish negative from positive values of time [Newton, by Coveney/Highfield] |
17015 | If there is no uniform motion, we cannot exactly measure time [Newton] |
17025 | If a perfect being does not rule the cosmos, it is not God [Newton] |
17024 | The elegance of the solar system requires a powerful intellect as designer [Newton] |