33 ideas
19275 | You cannot understand what exists without understanding possibility and necessity [Hale] |
19291 | A canonical defintion specifies the type of thing, and what distinguish this specimen [Hale] |
13591 | Quantified modal logic collapses if essence is withdrawn [Quine] |
19297 | The two Barcan principles are easily proved in fairly basic modal logic [Hale] |
19301 | With a negative free logic, we can dispense with the Barcan formulae [Hale] |
11211 | If a sound conclusion comes from two errors that cancel out, the path of the argument must matter [Rumfitt] |
19296 | If second-order variables range over sets, those are just objects; properties and relations aren't sets [Hale] |
19289 | Maybe conventionalism applies to meaning, but not to the truth of propositions expressed [Hale] |
11212 | The sense of a connective comes from primitively obvious rules of inference [Rumfitt] |
11210 | Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt] |
19298 | Unlike axiom proofs, natural deduction proofs needn't focus on logical truths and theorems [Hale] |
19295 | Add Hume's principle to logic, to get numbers; arithmetic truths rest on the nature of the numbers [Hale] |
19281 | Interesting supervenience must characterise the base quite differently from what supervenes on it [Hale] |
19278 | There is no gap between a fact that p, and it is true that p; so we only have the truth-condtions for p [Hale] |
19302 | If a chair could be made of slightly different material, that could lead to big changes [Hale] |
13590 | Essences can make sense in a particular context or enquiry, as the most basic predicates [Quine] |
19290 | Absolute necessities are necessarily necessary [Hale] |
19286 | 'Absolute necessity' is when there is no restriction on the things which necessitate p [Hale] |
19288 | Logical and metaphysical necessities differ in their vocabulary, and their underlying entities [Hale] |
19285 | Logical necessity is something which is true, no matter what else is the case [Hale] |
19287 | Maybe each type of logic has its own necessity, gradually becoming broader [Hale] |
8483 | Necessity is relative to context; it is what is assumed in an inquiry [Quine] |
19282 | It seems that we cannot show that modal facts depend on non-modal facts [Hale] |
19276 | The big challenge for essentialist views of modality is things having necessary existence [Hale] |
19293 | Essentialism doesn't explain necessity reductively; it explains all necessities in terms of a few basic natures [Hale] |
19294 | If necessity derives from essences, how do we explain the necessary existence of essences? [Hale] |
19279 | What are these worlds, that being true in all of them makes something necessary? [Hale] |
13589 | Possible worlds are a way to dramatise essentialism, and yet they presuppose essentialism [Quine] |
19299 | Possible worlds make every proposition true or false, which endorses classical logic [Hale] |
13588 | A rigid designator (for all possible worlds) picks out an object by its essential traits [Quine] |
13592 | Beliefs can be ascribed to machines [Quine] |
19300 | The molecules may explain the water, but they are not what 'water' means [Hale] |
11214 | We learn 'not' along with affirmation, by learning to either affirm or deny a sentence [Rumfitt] |