84 ideas
12865 | Analytic philosophers may prefer formal systems because natural language is such mess [Simons] |
13838 | A decent modern definition should always imply a semantics [Hacking] |
13833 | 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking] |
13834 | Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking] |
13835 | Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking] |
12832 | Complement: the rest of the Universe apart from some individual, written x-bar [Simons] |
12834 | Criticisms of mereology: parts? transitivity? sums? identity? four-dimensional? [Simons] |
12815 | Classical mereology doesn't apply well to the objects around us [Simons] |
12819 | A 'part' has different meanings for individuals, classes, and masses [Simons] |
12831 | Atom: an individual with no proper parts, written 'At x' [Simons] |
12844 | Dissective: stuff is dissective if parts of the stuff are always the stuff [Simons] |
12822 | Proper or improper part: x < y, 'x is (a) part of y' [Simons] |
12823 | Overlap: two parts overlap iff they have a part in common, expressed as 'x o y' [Simons] |
12824 | Disjoint: two individuals are disjoint iff they do not overlap, written 'x | y' [Simons] |
12827 | Difference: the difference of individuals is the remainder of an overlap, written 'x - y' [Simons] |
12828 | General sum: the sum of objects satisfying some predicate, written σx(Fx) [Simons] |
12825 | Product: the product of two individuals is the sum of all of their overlaps, written 'x · y' [Simons] |
12826 | Sum: the sum of individuals is what is overlapped if either of them are, written 'x + y' [Simons] |
12829 | General product: the nucleus of all objects satisfying a predicate, written πx(Fx) [Simons] |
12830 | Universe: the mereological sum of all objects whatever, written 'U' [Simons] |
12813 | Two standard formalisations of part-whole theory are the Calculus of Individuals, and Mereology [Simons] |
12816 | Classical mereology doesn't handle temporal or modal notions very well [Simons] |
12821 | The part-relation is transitive and asymmetric (and thus irreflexive) [Simons] |
18847 | Each wheel is part of a car, but the four wheels are not a further part [Simons] |
12846 | A 'group' is a collection with a condition which constitutes their being united [Simons] |
12861 | 'The wolves' are the matter of 'the pack'; the latter is a group, with different identity conditions [Simons] |
12848 | The same members may form two groups [Simons] |
13845 | The various logics are abstractions made from terms like 'if...then' in English [Hacking] |
13844 | A limitation of first-order logic is that it cannot handle branching quantifiers [Hacking] |
13840 | First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking] |
13842 | Second-order completeness seems to need intensional entities and possible worlds [Hacking] |
17896 | We need to know the meaning of 'and', prior to its role in reasoning [Prior,AN, by Belnap] |
17898 | Prior's 'tonk' is inconsistent, since it allows the non-conservative inference A |- B [Belnap on Prior,AN] |
11021 | Prior rejected accounts of logical connectives by inference pattern, with 'tonk' his absurd example [Prior,AN, by Read] |
13836 | Maybe introducing or defining logical connectives by rules of inference leads to absurdity [Prior,AN, by Hacking] |
13837 | With a pure notion of truth and consequence, the meanings of connectives are fixed syntactically [Hacking] |
13839 | Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking] |
12876 | Philosophy is stuck on the Fregean view that an individual is anything with a proper name [Simons] |
12845 | Some natural languages don't distinguish between singular and plural [Simons] |
13843 | If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking] |
12838 | Four-dimensional ontology has no change, since that needs an object, and time to pass [Simons] |
12842 | There are real relational changes, as well as bogus 'Cambridge changes' [Simons] |
12841 | I don't believe in processes [Simons] |
12836 | Fans of process ontology cheat, since river-stages refer to 'rivers' [Simons] |
12880 | Moments are things like smiles or skids, which are founded on other things [Simons] |
12882 | A wave is maintained by a process, but it isn't a process [Simons] |
12883 | Moving disturbances are are moments which continuously change their basis [Simons] |
12881 | A smiling is an event with causes, but the smile is a continuant without causes [Simons] |
12840 | I do not think there is a general identity condition for events [Simons] |
12839 | Relativity has an ontology of things and events, not on space-time diagrams [Simons] |
12879 | Independent objects can exist apart, and maybe even entirely alone [Simons] |
12847 | Mass nouns admit 'much' and 'a little', and resist 'many' and 'few'. [Simons] |
12862 | Gold is not its atoms, because the atoms must be all gold, but gold contains neutrons [Simons] |
12863 | Mass terms (unlike plurals) are used with indifference to whether they can exist in units [Simons] |
12859 | A mixture can have different qualities from its ingredients. [Simons] |
12858 | Mixtures disappear if nearly all of the mixture is one ingredient [Simons] |
12850 | To individuate something we must pick it out, but also know its limits of variation [Simons] |
12860 | Sortal nouns for continuants tell you their continuance- and cessation-conditions [Simons] |
12886 | A whole requires some unique relation which binds together all of the parts [Simons] |
12857 | Tibbles isn't Tib-plus-tail, because Tibbles can survive its loss, but the sum can't [Simons] |
12835 | Does Tibbles remain the same cat when it loses its tail? [Simons] |
12820 | Without extensional mereology two objects can occupy the same position [Simons] |
12866 | Composition is asymmetric and transitive [Simons] |
12867 | A hand constitutes a fist (when clenched), but a fist is not composed of an augmented hand [Simons] |
12864 | We say 'b is part of a', 'b is a part of a', 'b are a part of a', or 'b are parts of a'. [Simons] |
12817 | 'Mereological extensionality' says objects with the same parts are identical [Simons] |
12814 | Classical mereology says there are 'sums', for whose existence there is no other evidence [Simons] |
12833 | If there are c atoms, this gives 2^c - 1 individuals, so there can't be just 2 or 12 individuals [Simons] |
12849 | Sums are more plausible for pluralities and masses than they are for individuals [Simons] |
12877 | Sums of things in different categories are found within philosophy. [Simons] |
12888 | The wholeness of a melody seems conventional, but of an explosion it seems natural [Simons] |
12871 | Objects have their essential properties because of the kind of objects they are [Simons] |
12870 | We must distinguish the de dicto 'must' of propositions from the de re 'must' of essence [Simons] |
12873 | Original parts are the best candidates for being essential to artefacts [Simons] |
12874 | An essential part of an essential part is an essential part of the whole [Simons] |
12837 | Four dimensional-objects are stranger than most people think [Simons] |
12856 | Intermittent objects would be respectable if they occurred in nature, as well as in artefacts [Simons] |
12885 | Objects like chess games, with gaps in them, are thereby less unified [Simons] |
12854 | An entrepreneur and a museum curator would each be happy with their ship at the end [Simons] |
12855 | The 'best candidate' theories mistakenly assume there is one answer to 'Which is the real ship?' [Simons] |
12872 | The zygote is an essential initial part, for a sexually reproduced organism [Simons] |
12889 | The limits of change for an individual depend on the kind of individual [Simons] |
12843 | With activities if you are doing it you've done it, with performances you must finish to have done it [Simons] |
12875 | One false note doesn't make it a performance of a different work [Simons] |