87 ideas
| 21959 | Metaphysics is the most general attempt to make sense of things [Moore,AW] |
| 2474 | It seems likely that analysis of concepts is impossible, but justification can survive without it [Fodor] |
| 2481 | Despite all the efforts of philosophers, nothing can ever be reduced to anything [Fodor] |
| 2505 | Turing invented the idea of mechanical rationality (just based on syntax) [Fodor] |
| 2470 | Transcendental arguments move from knowing Q to knowing P because it depends on Q [Fodor] |
| 9738 | Each line of a truth table is a model [Fitting/Mendelsohn] |
| 9727 | Modal logic adds □ (necessarily) and ◊ (possibly) to classical logic [Fitting/Mendelsohn] |
| 9726 | We let 'R' be the accessibility relation: xRy is read 'y is accessible from x' [Fitting/Mendelsohn] |
| 9737 | The symbol ||- is the 'forcing' relation; 'Γ ||- P' means that P is true in world Γ [Fitting/Mendelsohn] |
| 13136 | The prefix σ names a possible world, and σ.n names a world accessible from that one [Fitting/Mendelsohn] |
| 13727 | A 'constant' domain is the same for all worlds; 'varying' domains can be entirely separate [Fitting/Mendelsohn] |
| 9734 | Modern modal logic introduces 'accessibility', saying xRy means 'y is accessible from x' [Fitting/Mendelsohn] |
| 9736 | A 'model' is a frame plus specification of propositions true at worlds, written < G,R,||- > [Fitting/Mendelsohn] |
| 9735 | A 'frame' is a set G of possible worlds, with an accessibility relation R, written < G,R > [Fitting/Mendelsohn] |
| 9741 | Accessibility relations can be 'reflexive' (self-referring), 'transitive' (carries over), or 'symmetric' (mutual) [Fitting/Mendelsohn] |
| 13149 | S5: a) if n ◊X then kX b) if n ¬□X then k ¬X c) if n □X then k X d) if n ¬◊X then k ¬X [Fitting/Mendelsohn] |
| 13141 | Negation: if σ ¬¬X then σ X [Fitting/Mendelsohn] |
| 13138 | Disj: a) if σ ¬(X∨Y) then σ ¬X and σ ¬Y b) if σ X∨Y then σ X or σ Y [Fitting/Mendelsohn] |
| 13142 | Existential: a) if σ ◊X then σ.n X b) if σ ¬□X then σ.n ¬X [n is new] [Fitting/Mendelsohn] |
| 13144 | T reflexive: a) if σ □X then σ X b) if σ ¬◊X then σ ¬X [Fitting/Mendelsohn] |
| 13145 | D serial: a) if σ □X then σ ◊X b) if σ ¬◊X then σ ¬□X [Fitting/Mendelsohn] |
| 13146 | B symmetric: a) if σ.n □X then σ X b) if σ.n ¬◊X then σ ¬X [n occurs] [Fitting/Mendelsohn] |
| 13147 | 4 transitive: a) if σ □X then σ.n □X b) if σ ¬◊X then σ.n ¬◊X [n occurs] [Fitting/Mendelsohn] |
| 13148 | 4r rev-trans: a) if σ.n □X then σ □X b) if σ.n ¬◊X then σ ¬◊X [n occurs] [Fitting/Mendelsohn] |
| 9740 | If a proposition is possibly true in a world, it is true in some world accessible from that world [Fitting/Mendelsohn] |
| 9739 | If a proposition is necessarily true in a world, it is true in all worlds accessible from that world [Fitting/Mendelsohn] |
| 13137 | Conj: a) if σ X∧Y then σ X and σ Y b) if σ ¬(X∧Y) then σ ¬X or σ ¬Y [Fitting/Mendelsohn] |
| 13140 | Bicon: a)if σ(X↔Y) then σ(X→Y) and σ(Y→X) b) [not biconditional, one or other fails] [Fitting/Mendelsohn] |
| 13139 | Implic: a) if σ ¬(X→Y) then σ X and σ ¬Y b) if σ X→Y then σ ¬X or σ Y [Fitting/Mendelsohn] |
| 13143 | Universal: a) if σ ¬◊X then σ.m ¬X b) if σ □X then σ.m X [m exists] [Fitting/Mendelsohn] |
| 9742 | The system K has no accessibility conditions [Fitting/Mendelsohn] |
| 13114 | □P → P is not valid in D (Deontic Logic), since an obligatory action may be not performed [Fitting/Mendelsohn] |
| 9743 | The system D has the 'serial' conditon imposed on its accessibility relation [Fitting/Mendelsohn] |
| 9744 | The system T has the 'reflexive' conditon imposed on its accessibility relation [Fitting/Mendelsohn] |
| 9746 | The system K4 has the 'transitive' condition on its accessibility relation [Fitting/Mendelsohn] |
| 9745 | The system B has the 'reflexive' and 'symmetric' conditions on its accessibility relation [Fitting/Mendelsohn] |
| 9747 | The system S4 has the 'reflexive' and 'transitive' conditions on its accessibility relation [Fitting/Mendelsohn] |
| 9748 | System S5 has the 'reflexive', 'symmetric' and 'transitive' conditions on its accessibility relation [Fitting/Mendelsohn] |
| 9404 | Modality affects content, because P→◊P is valid, but ◊P→P isn't [Fitting/Mendelsohn] |
| 13112 | In epistemic logic knowers are logically omniscient, so they know that they know [Fitting/Mendelsohn] |
| 13111 | Read epistemic box as 'a knows/believes P' and diamond as 'for all a knows/believes, P' [Fitting/Mendelsohn] |
| 13113 | F: will sometime, P: was sometime, G: will always, H: was always [Fitting/Mendelsohn] |
| 13728 | The Barcan says nothing comes into existence; the Converse says nothing ceases; the pair imply stability [Fitting/Mendelsohn] |
| 13729 | The Barcan corresponds to anti-monotonicity, and the Converse to monotonicity [Fitting/Mendelsohn] |
| 9725 | 'Predicate abstraction' abstracts predicates from formulae, giving scope for constants and functions [Fitting/Mendelsohn] |
| 2469 | The world is full of messy small things producing stable large-scale properties (e.g. mountains) [Fodor] |
| 2475 | Don't define something by a good instance of it; a good example is a special case of the ordinary example [Fodor] |
| 13730 | The Indiscernibility of Identicals has been a big problem for modal logic [Fitting/Mendelsohn] |
| 13725 | □ must be sensitive as to whether it picks out an object by essential or by contingent properties [Fitting/Mendelsohn] |
| 13731 | Objects retain their possible properties across worlds, so a bundle theory of them seems best [Fitting/Mendelsohn] |
| 13726 | Counterpart relations are neither symmetric nor transitive, so there is no logic of equality for them [Fitting/Mendelsohn] |
| 2502 | How do you count beliefs? [Fodor] |
| 21958 | Appearances are nothing beyond representations, which is transcendental ideality [Moore,AW] |
| 2501 | Berkeley seems to have mistakenly thought that chairs are the same as after-images [Fodor] |
| 2465 | Maybe explaining the mechanics of perception will explain the concepts involved [Fodor] |
| 2504 | Rationalism can be based on an evolved computational brain with innate structure [Fodor] |
| 2493 | According to empiricists abstraction is the fundamental mental process [Fodor] |
| 2494 | Rationalists say there is more to a concept than the experience that prompts it [Fodor] |
| 2503 | Empirical approaches see mind connections as mirrors/maps of reality [Fodor] |
| 2508 | The function of a mind is obvious [Fodor] |
| 2485 | Do intentional states explain our behaviour? [Fodor] |
| 2506 | If I have a set of mental modules, someone had better be in charge of them! [Fodor] |
| 2467 | Functionalists see pains as properties involving relations and causation [Fodor] |
| 2489 | Why bother with neurons? You don't explain bird flight by examining feathers [Fodor] |
| 2468 | Type physicalism is a stronger claim than token physicalism [Fodor] |
| 2490 | Modern connectionism is just Hume's theory of the 'association' of 'ideas' [Fodor] |
| 2476 | The goal of thought is to understand the world, not instantly sort it into conceptual categories [Fodor] |
| 2499 | Modules analyse stimuli, they don't tell you what to do [Fodor] |
| 2496 | Blindness doesn't destroy spatial concepts [Fodor] |
| 2497 | Something must take an overview of the modules [Fodor] |
| 2509 | Modules have in-built specialist information [Fodor] |
| 2491 | Modules have encapsulation, inaccessibility, private concepts, innateness [Fodor] |
| 2495 | Obvious modules are language and commonsense explanation [Fodor] |
| 2498 | Modules make the world manageable [Fodor] |
| 2500 | Babies talk in consistent patterns [Fodor] |
| 2507 | Rationality rises above modules [Fodor] |
| 2480 | Language is ambiguous, but thought isn't [Fodor] |
| 2487 | Mentalese may also incorporate some natural language [Fodor] |
| 2483 | Mentalese doesn't require a theory of meaning [Fodor] |
| 2486 | Content can't be causal role, because causal role is decided by content [Fodor] |
| 2492 | Experience can't explain itself; the concepts needed must originate outside experience [Fodor] |
| 2471 | Are concepts best seen as capacities? [Fodor] |
| 2472 | For Pragmatists having a concept means being able to do something [Fodor] |
| 2482 | It seems unlikely that meaning can be reduced to communicative intentions, or any mental states [Fodor] |
| 2477 | If to understand "fish" you must know facts about them, where does that end? [Fodor] |
| 2473 | Analysis is impossible without the analytic/synthetic distinction [Fodor] |
| 2484 | The theory of the content of thought as 'Mentalese' explains why the Private Language Argument doesn't work [Fodor] |