94 ideas
15010 | Your metaphysics is 'cheating' if your ontology won't support the beliefs you accept [Sider] |
14977 | Metaphysics is not about what exists or is true or essential; it is about the structure of reality [Sider] |
14994 | Extreme doubts about metaphysics also threaten to undermine the science of unobservables [Sider] |
15003 | It seems unlikely that the way we speak will give insights into the universe [Sider] |
14986 | Conceptual analysts trust particular intuitions much more than general ones [Sider] |
21546 | We can't sharply distinguish variables, domains and values, if symbols frighten us [Russell] |
15015 | It seems possible for a correct definition to be factually incorrect, as in defining 'contact' [Sider] |
14981 | Philosophical concepts are rarely defined, and are not understood by means of definitions [Sider] |
14992 | We don't care about plain truth, but truth in joint-carving terms [Sider] |
15012 | Orthodox truthmaker theories make entities fundamental, but that is poor for explanation [Sider] |
10987 | Three traditional names of rules are 'Simplification', 'Addition' and 'Disjunctive Syllogism' [Read] |
11004 | Necessity is provability in S4, and true in all worlds in S5 [Read] |
15023 | The Barcan schema implies if X might have fathered something, there is something X might have fathered [Sider] |
11018 | There are fuzzy predicates (and sets), and fuzzy quantifiers and modifiers [Read] |
11011 | Same say there are positive, negative and neuter free logics [Read] |
11020 | Realisms like the full Comprehension Principle, that all good concepts determine sets [Read] |
15004 | 'Gunk' is an object in which proper parts all endlessly have further proper parts [Sider] |
14984 | Which should be primitive in mereology - part, or overlap? [Sider] |
14980 | There is a real issue over what is the 'correct' logic [Sider] |
15000 | 'It is raining' and 'it is not raining' can't be legislated, so we can't legislate 'p or ¬p' [Sider] |
10986 | Not all validity is captured in first-order logic [Read] |
10972 | The non-emptiness of the domain is characteristic of classical logic [Read] |
15020 | Classical logic is good for mathematics and science, but less good for natural language [Sider] |
11024 | Semantics must precede proof in higher-order logics, since they are incomplete [Read] |
10985 | We should exclude second-order logic, precisely because it captures arithmetic [Read] |
10970 | A theory of logical consequence is a conceptual analysis, and a set of validity techniques [Read] |
10984 | Logical consequence isn't just a matter of form; it depends on connections like round-square [Read] |
15029 | Modal accounts of logical consequence are simple necessity, or essential use of logical words [Sider] |
15019 | Define logical constants by role in proofs, or as fixed in meaning, or as topic-neutral [Sider] |
10973 | A theory is logically closed, which means infinite premisses [Read] |
11007 | Quantifiers are second-order predicates [Read] |
10978 | In second-order logic the higher-order variables range over all the properties of the objects [Read] |
15001 | 'Tonk' is supposed to follow the elimination and introduction rules, but it can't be so interpreted [Sider] |
10971 | A logical truth is the conclusion of a valid inference with no premisses [Read] |
10988 | Any first-order theory of sets is inadequate [Read] |
10974 | Compactness is when any consequence of infinite propositions is the consequence of a finite subset [Read] |
10975 | Compactness does not deny that an inference can have infinitely many premisses [Read] |
10977 | Compactness blocks the proof of 'for every n, A(n)' (as the proof would be infinite) [Read] |
10976 | Compactness makes consequence manageable, but restricts expressive power [Read] |
11014 | Self-reference paradoxes seem to arise only when falsity is involved [Read] |
11025 | Infinite cuts and successors seems to suggest an actual infinity there waiting for us [Read] |
10979 | Although second-order arithmetic is incomplete, it can fully model normal arithmetic [Read] |
10980 | Second-order arithmetic covers all properties, ensuring categoricity [Read] |
10997 | Von Neumann numbers are helpful, but don't correctly describe numbers [Read] |
15017 | Supervenience is a modal connection [Sider] |
15008 | Is fundamentality in whole propositions (and holistic), or in concepts (and atomic)? [Sider] |
15013 | Tables and chairs have fundamental existence, but not fundamental natures [Sider] |
15014 | Unlike things, stuff obeys unrestricted composition and mereological essentialism [Sider] |
15009 | We must distinguish 'concrete' from 'abstract' and necessary states of affairs. [Sider] |
11016 | Would a language without vagueness be usable at all? [Read] |
11013 | Identities and the Indiscernibility of Identicals don't work with supervaluations [Read] |
11012 | A 'supervaluation' gives a proposition consistent truth-value for classical assignments [Read] |
11019 | Supervaluations say there is a cut-off somewhere, but at no particular place [Read] |
14983 | Accept the ontology of your best theory - and also that it carves nature at the joints [Sider] |
14978 | A property is intrinsic if an object alone in the world can instantiate it [Sider] |
14995 | Predicates can be 'sparse' if there is a universal, or if there is a natural property or relation [Sider] |
21531 | Common sense agrees with Meinong (rather than Russell) that 'Pegasus is a flying horse' is true [Lackey on Russell] |
21545 | I prefer to deny round squares, and deal with the difficulties by the theory of denoting [Russell] |
10995 | A haecceity is a set of individual properties, essential to each thing [Read] |
15026 | Essence (even if nonmodal) is not fundamental in metaphysics [Sider] |
11001 | Equating necessity with truth in every possible world is the S5 conception of necessity [Read] |
10989 | The standard view of conditionals is that they are truth-functional [Read] |
10992 | The point of conditionals is to show that one will accept modus ponens [Read] |
11017 | Some people even claim that conditionals do not express propositions [Read] |
15030 | Humeans say that we decide what is necessary [Sider] |
15031 | Modal terms in English are entirely contextual, with no modality outside the language [Sider] |
15028 | Conventionalism doesn't seem to apply to examples of the necessary a posteriori [Sider] |
15027 | If truths are necessary 'by convention', that seems to make them contingent [Sider] |
15033 | Humeans says mathematics and logic are necessary because that is how our concept of necessity works [Sider] |
15025 | The world does not contain necessity and possibility - merely how things are [Sider] |
10983 | Knowledge of possible worlds is not causal, but is an ontology entailed by semantics [Read] |
10982 | How can modal Platonists know the truth of a modal proposition? [Read] |
10996 | Actualism is reductionist (to parts of actuality), or moderate realist (accepting real abstractions) [Read] |
10981 | A possible world is a determination of the truth-values of all propositions of a domain [Read] |
11000 | If worlds are concrete, objects can't be present in more than one, and can only have counterparts [Read] |
14988 | A theory which doesn't fit nature is unexplanatory, even if it is true [Sider] |
14982 | If I used Ramsey sentences to eliminate fundamentality from my theory, that would be a real loss [Sider] |
14989 | Problem predicates in induction don't reflect the structure of nature [Sider] |
14997 | Two applications of 'grue' do not guarantee a similarity between two things [Sider] |
14990 | Bayes produces weird results if the prior probabilities are bizarre [Sider] |
15005 | Explanations must cite generalisations [Sider] |
15011 | If the ultimate explanation is a list of entities, no laws, patterns or mechanisms can be cited [Sider] |
15018 | Intentionality is too superficial to appear in the catalogue of ultimate physics [Sider] |
10998 | The mind abstracts ways things might be, which are nonetheless real [Read] |
14999 | Prior to conventions, not all green things were green? [Sider] |
11005 | Negative existentials with compositionality make the whole sentence meaningless [Read] |
10966 | A proposition objectifies what a sentence says, as indicative, with secure references [Read] |
14998 | Conventions are contingent and analytic truths are necessary, so that isn't their explanation [Sider] |
15016 | Analyticity has lost its traditional role, which relied on truth by convention [Sider] |
14987 | Many of the key theories of modern physics do not appear to be 'laws' [Sider] |
14985 | The notion of law doesn't seem to enhance physical theories [Sider] |
14991 | Space has real betweenness and congruence structure (though it is not the Euclidean concepts) [Sider] |
15021 | The central question in the philosophy of time is: How alike are time and space? [Sider] |
15024 | The spotlight theorists accepts eternal time, but with a spotlight of the present moving across it [Sider] |