27 ideas
7791 | The simplest of the logics based on possible worlds is Lewis's S5 [Lewis,CI, by Girle] |
15375 | If terms change their designations in different states, they are functions from states to objects [Fitting] |
15376 | Intensional logic adds a second type of quantification, over intensional objects, or individual concepts [Fitting] |
15378 | Awareness logic adds the restriction of an awareness function to epistemic logic [Fitting] |
15379 | Justication logics make explicit the reasons for mathematical truth in proofs [Fitting] |
9358 | There are several logics, none of which will ever derive falsehoods from truth [Lewis,CI] |
11026 | Classical logic is deliberately extensional, in order to model mathematics [Fitting] |
9357 | Excluded middle is just our preference for a simplified dichotomy in experience [Lewis,CI] |
9364 | Names represent a uniformity in experience, or they name nothing [Lewis,CI] |
11028 | λ-abstraction disambiguates the scope of modal operators [Fitting] |
11002 | Equating necessity with informal provability is the S4 conception of necessity [Lewis,CI, by Read] |
9362 | Necessary truths are those we will maintain no matter what [Lewis,CI] |
22142 | In future, only logical limits can be placed on divine omnipotence [Anon (Par), by Boulter] |
7803 | Modal logic began with translation difficulties for 'If...then' [Lewis,CI, by Girle] |
15377 | Definite descriptions pick out different objects in different possible worlds [Fitting] |
9365 | We can maintain a priori principles come what may, but we can also change them [Lewis,CI] |
21500 | We rely on memory for empirical beliefs because they mutually support one another [Lewis,CI] |
21501 | If we doubt memories we cannot assess our doubt, or what is being doubted [Lewis,CI] |
6556 | If anything is to be probable, then something must be certain [Lewis,CI] |
16716 | It is heresy to require self-evident foundational principles in order to be certain [Anon (Par)] |
21498 | Congruents assertions increase the probability of each individual assertion in the set [Lewis,CI] |
5828 | Extension is the class of things, intension is the correct definition of the thing, and intension determines extension [Lewis,CI] |
9361 | We have to separate the mathematical from physical phenomena by abstraction [Lewis,CI] |
1866 | It is heresy to teach that history repeats every 36,000 years [Anon (Par)] |
9363 | Science seeks classification which will discover laws, essences, and predictions [Lewis,CI] |
1865 | It is heresy to teach that natural impossibilities cannot even be achieved by God [Anon (Par)] |
1864 | It is heresy to teach that we can know God by his essence in this mortal life [Anon (Par)] |