80 ideas
| 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] |
| 8625 | What physical facts could underlie 0 or 1, or very large numbers? [Frege on Mill] |
| 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] |
| 17895 | Combining two distinct assertions does not necessarily lead to a single 'complex proposition' [Mill] |
| 10036 | In 'Principia' a new abstract theory of relations appeared, and was applied [Russell/Whitehead, by Gödel] |
| 10427 | All names are names of something, real or imaginary [Mill] |
| 4944 | Mill says names have denotation but not connotation [Mill, by Kripke] |
| 7762 | Proper names are just labels for persons or objects, and the meaning is the object [Mill, by Lycan] |
| 18248 | A real number is the class of rationals less than the number [Russell/Whitehead, by Shapiro] |
| 9801 | Numbers must be assumed to have identical units, as horses are equalised in 'horse-power' [Mill] |
| 8742 | The only axioms needed are for equality, addition, and successive numbers [Mill, by Shapiro] |
| 18152 | Russell takes numbers to be classes, but then reduces the classes to numerical quantifiers [Russell/Whitehead, by Bostock] |
| 9800 | Arithmetic is based on definitions, and Sums of equals are equal, and Differences of equals are equal [Mill] |
| 5201 | Mill says logic and maths is induction based on a very large number of instances [Mill, by Ayer] |
| 9360 | If two black and two white objects in practice produced five, what colour is the fifth one? [Lewis,CI on Mill] |
| 9888 | Mill mistakes particular applications as integral to arithmetic, instead of general patterns [Dummett on Mill] |
| 9794 | There are no such things as numbers in the abstract [Mill] |
| 9796 | Things possess the properties of numbers, as quantity, and as countable parts [Mill] |
| 9795 | Numbers have generalised application to entities (such as bodies or sounds) [Mill] |
| 9798 | Different parcels made from three pebbles produce different actual sensations [Mill] |
| 9797 | '2 pebbles and 1 pebble' and '3 pebbles' name the same aggregation, but different facts [Mill] |
| 9799 | 3=2+1 presupposes collections of objects ('Threes'), which may be divided thus [Mill] |
| 9802 | Numbers denote physical properties of physical phenomena [Mill] |
| 9803 | We can't easily distinguish 102 horses from 103, but we could arrange them to make it obvious [Mill] |
| 9804 | Arithmetical results give a mode of formation of a given number [Mill] |
| 9805 | 12 is the cube of 1728 means pebbles can be aggregated a certain way [Mill] |
| 8741 | Numbers must be of something; they don't exist as abstractions [Mill] |
| 12411 | Mill is too imprecise, and is restricted to simple arithmetic [Kitcher on Mill] |
| 5656 | Empirical theories of arithmetic ignore zero, limit our maths, and need probability to get started [Frege on Mill] |
| 9624 | Numbers are a very general property of objects [Mill, by Brown,JR] |
| 10025 | Russell and Whitehead took arithmetic to be higher-order logic [Russell/Whitehead, by Hodes] |
| 8683 | Russell and Whitehead were not realists, but embraced nearly all of maths in logic [Russell/Whitehead, by Friend] |
| 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] |
| 9806 | Whatever is made up of parts is made up of parts of those parts [Mill] |
| 11156 | The essence is that without which a thing can neither be, nor be conceived to be [Mill] |
| 12033 | An object is identical with itself, and no different indiscernible object can share that [Russell/Whitehead, by Adams,RM] |
| 12190 | Necessity is what will be, despite any alternative suppositions whatever [Mill] |
| 22623 | Necessity can only mean what must be, without conditions of any kind [Mill] |
| 16859 | Most perception is one-tenth observation and nine-tenths inference [Mill] |
| 9082 | Clear concepts result from good observation, extensive experience, and accurate memory [Mill] |
| 10040 | Russell showed, through the paradoxes, that our basic logical intuitions are self-contradictory [Russell/Whitehead, by Gödel] |
| 16860 | Inductive generalisation is more reliable than one of its instances; they can't all be wrong [Mill] |
| 16845 | The whole theory of induction rests on causes [Mill] |
| 16843 | Mill's methods (Difference,Agreement,Residues,Concomitance,Hypothesis) don't nail induction [Mill, by Lipton] |
| 17086 | Surprisingly, empiricists before Mill ignore explanation, which seems to transcend experience [Mill, by Ruben] |
| 17091 | Explanation is fitting of facts into ever more general patterns of regularity [Mill, by Ruben] |
| 16805 | Causal inference is by spotting either Agreements or Differences [Mill, by Lipton] |
| 16835 | The Methods of Difference and of Agreement are forms of inference to the best explanation [Mill, by Lipton] |
| 9079 | We can focus our minds on what is common to a whole class, neglecting other aspects [Mill] |
| 9081 | We don't recognise comparisons by something in our minds; the concepts result from the comparisons [Mill] |
| 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] |
| 9080 | General conceptions are a necessary preliminary to Induction [Mill] |
| 9078 | The study of the nature of Abstract Ideas does not belong to logic, but to a different science [Mill] |
| 23453 | Propositions as objects of judgement don't exist, because we judge several objects, not one [Russell/Whitehead] |
| 20327 | Modern attention has moved from the intrinsic properties of art to its relational properties [Lamarque/Olson] |
| 20326 | Early 20th cent attempts at defining art focused on significant form, intuition, expression, unity [Lamarque/Olson] |
| 20330 | The dualistic view says works of art are either abstract objects (types), or physical objects [Lamarque/Olson] |
| 8345 | A cause is the total of all the conditions which inevitably produce the result [Mill] |
| 10391 | Causes and conditions are not distinct, because we select capriciously from among them [Mill] |
| 14547 | The strict cause is the total positive and negative conditions which ensure the consequent [Mill] |
| 8377 | Causation is just invariability of succession between every natural fact and a preceding fact [Mill] |
| 14545 | A cause is an antecedent which invariably and unconditionally leads to a phenomenon [Mill] |
| 4773 | Mill's regularity theory of causation is based on an effect preceded by a conjunction of causes [Mill, by Psillos] |
| 4775 | In Mill's 'Method of Agreement' cause is the common factor in a range of different cases [Mill, by Psillos] |
| 4776 | In Mill's 'Method of Difference' the cause is what stops the effect when it is removed [Mill, by Psillos] |
| 9417 | What are the fewest propositions from which all natural uniformities could be inferred? [Mill] |