53 ideas
| 7085 | The main problem of philosophy is what can and cannot be thought and expressed [Wittgenstein, by Grayling] |
| 6420 | Only by analysing is progress possible in philosophy [Russell] |
| 6432 | Analysis gives new knowledge, without destroying what we already have [Russell] |
| 6437 | The theory of types makes 'Socrates and killing are two' illegitimate [Russell] |
| 6442 | Truth belongs to beliefs, not to propositions and sentences [Russell] |
| 14684 | A world is 'accessible' to another iff the first is possible according to the second [Salmon,N] |
| 14669 | For metaphysics, T may be the only correct system of modal logic [Salmon,N] |
| 14667 | System B has not been justified as fallacy-free for reasoning on what might have been [Salmon,N] |
| 14668 | In B it seems logically possible to have both p true and p is necessarily possibly false [Salmon,N] |
| 14692 | System B implies that possibly-being-realized is an essential property of the world [Salmon,N] |
| 14671 | What is necessary is not always necessarily necessary, so S4 is fallacious [Salmon,N] |
| 14686 | S5 modal logic ignores accessibility altogether [Salmon,N] |
| 14691 | S5 believers say that-things-might-have-been-that-way is essential to ways things might have been [Salmon,N] |
| 14693 | The unsatisfactory counterpart-theory allows the retention of S5 [Salmon,N] |
| 14670 | Metaphysical (alethic) modal logic concerns simple necessity and possibility (not physical, epistemic..) [Salmon,N] |
| 6436 | I gradually replaced classes with properties, and they ended as a symbolic convenience [Russell] |
| 7528 | Leibniz bases everything on subject/predicate and substance/property propositions [Russell] |
| 6439 | Names are meaningless unless there is an object which they designate [Russell] |
| 6423 | We tried to define all of pure maths using logical premisses and concepts [Russell] |
| 6424 | Formalists say maths is merely conventional marks on paper, like the arbitrary rules of chess [Russell] |
| 6425 | Formalism can't apply numbers to reality, so it is an evasion [Russell] |
| 6426 | Intuitionism says propositions are only true or false if there is a method of showing it [Russell] |
| 23463 | Atomic facts correspond to true elementary propositions [Wittgenstein] |
| 6419 | In 1899-1900 I adopted the philosophy of logical atomism [Russell] |
| 6438 | Complex things can be known, but not simple things [Russell] |
| 6434 | Facts are everything, except simples; they are either relations or qualities [Russell] |
| 6440 | Universals can't just be words, because words themselves are universals [Russell] |
| 14678 | Any property is attached to anything in some possible world, so I am a radical anti-essentialist [Salmon,N] |
| 14680 | Logical possibility contains metaphysical possibility, which contains nomological possibility [Salmon,N] |
| 14690 | In the S5 account, nested modalities may be unseen, but they are still there [Salmon,N] |
| 14677 | Metaphysical necessity is said to be unrestricted necessity, true in every world whatsoever [Salmon,N] |
| 14679 | Bizarre identities are logically but not metaphysically possible, so metaphysical modality is restricted [Salmon,N] |
| 14688 | Without impossible worlds, the unrestricted modality that is metaphysical has S5 logic [Salmon,N] |
| 14685 | Metaphysical necessity is NOT truth in all (unrestricted) worlds; necessity comes first, and is restricted [Salmon,N] |
| 14681 | Logical necessity is free of constraints, and may accommodate all of S5 logic [Salmon,N] |
| 14676 | Nomological necessity is expressed with intransitive relations in modal semantics [Salmon,N] |
| 14689 | Necessity and possibility are not just necessity and possibility according to the actual world [Salmon,N] |
| 14674 | Impossible worlds are also ways for things to be [Salmon,N] |
| 14682 | Denial of impossible worlds involves two different confusions [Salmon,N] |
| 14687 | Without impossible worlds, how things might have been is the only way for things to be [Salmon,N] |
| 14683 | Possible worlds rely on what might have been, so they can' be used to define or analyse modality [Salmon,N] |
| 14672 | Possible worlds are maximal abstract ways that things might have been [Salmon,N] |
| 14675 | Possible worlds just have to be 'maximal', but they don't have to be consistent [Salmon,N] |
| 14673 | You can't define worlds as sets of propositions, and then define propositions using worlds [Salmon,N] |
| 6430 | In epistemology we should emphasis the continuity between animal and human minds [Russell] |
| 6441 | Pragmatism judges by effects, but I judge truth by causes [Russell] |
| 6431 | Empiricists seem unclear what they mean by 'experience' [Russell] |
| 6444 | True belief about the time is not knowledge if I luckily observe a stopped clock at the right moment [Russell] |
| 6433 | Behaviourists struggle to explain memory and imagination, because they won't admit images [Russell] |
| 6443 | Surprise is a criterion of error [Russell] |
| 6427 | Unverifiable propositions about the remote past are still either true or false [Russell] |
| 6435 | You can believe the meaning of a sentence without thinking of the words [Russell] |
| 23490 | A thought is mental constituents that relate to reality as words do [Wittgenstein] |