103 ideas
| 9641 | Definitions should be replaceable by primitives, and should not be creative [Brown,JR] |
| 10170 | While true-in-a-model seems relative, true-in-all-models seems not to be [Reck/Price] |
| 9634 | Set theory says that natural numbers are an actual infinity (to accommodate their powerset) [Brown,JR] |
| 10166 | ZFC set theory has only 'pure' sets, without 'urelements' [Reck/Price] |
| 9613 | Naïve set theory assumed that there is a set for every condition [Brown,JR] |
| 9615 | Nowadays conditions are only defined on existing sets [Brown,JR] |
| 9617 | The 'iterative' view says sets start with the empty set and build up [Brown,JR] |
| 9642 | A flock of birds is not a set, because a set cannot go anywhere [Brown,JR] |
| 9605 | If a proposition is false, then its negation is true [Brown,JR] |
| 10175 | Three types of variable in second-order logic, for objects, functions, and predicates/sets [Reck/Price] |
| 9649 | Axioms are either self-evident, or stipulations, or fallible attempts [Brown,JR] |
| 9638 | Berry's Paradox finds a contradiction in the naming of huge numbers [Brown,JR] |
| 9604 | Mathematics is the only place where we are sure we are right [Brown,JR] |
| 9622 | 'There are two apples' can be expressed logically, with no mention of numbers [Brown,JR] |
| 10165 | 'Analysis' is the theory of the real numbers [Reck/Price] |
| 9648 | π is a 'transcendental' number, because it is not the solution of an equation [Brown,JR] |
| 9621 | Mathematics represents the world through structurally similar models. [Brown,JR] |
| 9646 | There is no limit to how many ways something can be proved in mathematics [Brown,JR] |
| 9647 | Computers played an essential role in proving the four-colour theorem of maps [Brown,JR] |
| 10174 | Mereological arithmetic needs infinite objects, and function definitions [Reck/Price] |
| 10164 | Peano Arithmetic can have three second-order axioms, plus '1' and 'successor' [Reck/Price] |
| 10172 | Set-theory gives a unified and an explicit basis for mathematics [Reck/Price] |
| 9643 | Set theory may represent all of mathematics, without actually being mathematics [Brown,JR] |
| 9644 | When graphs are defined set-theoretically, that won't cover unlabelled graphs [Brown,JR] |
| 10167 | Structuralism emerged from abstract algebra, axioms, and set theory and its structures [Reck/Price] |
| 10169 | Relativist Structuralism just stipulates one successful model as its arithmetic [Reck/Price] |
| 10179 | There are 'particular' structures, and 'universal' structures (what the former have in common) [Reck/Price] |
| 10181 | Pattern Structuralism studies what isomorphic arithmetic models have in common [Reck/Price] |
| 10182 | There are Formalist, Relativist, Universalist and Pattern structuralism [Reck/Price] |
| 10168 | Formalist Structuralism says the ontology is vacuous, or formal, or inference relations [Reck/Price] |
| 10178 | Maybe we should talk of an infinity of 'possible' objects, to avoid arithmetic being vacuous [Reck/Price] |
| 9625 | To see a structure in something, we must already have the idea of the structure [Brown,JR] |
| 10176 | Universalist Structuralism is based on generalised if-then claims, not one particular model [Reck/Price] |
| 10177 | Universalist Structuralism eliminates the base element, as a variable, which is then quantified out [Reck/Price] |
| 9628 | Sets seem basic to mathematics, but they don't suit structuralism [Brown,JR] |
| 10171 | The existence of an infinite set is assumed by Relativist Structuralism [Reck/Price] |
| 9606 | The irrationality of root-2 was achieved by intellect, not experience [Brown,JR] |
| 9612 | There is an infinity of mathematical objects, so they can't be physical [Brown,JR] |
| 9610 | Numbers are not abstracted from particulars, because each number is a particular [Brown,JR] |
| 9620 | Empiricists base numbers on objects, Platonists base them on properties [Brown,JR] |
| 9639 | Does some mathematics depend entirely on notation? [Brown,JR] |
| 9629 | For nomalists there are no numbers, only numerals [Brown,JR] |
| 9630 | The most brilliant formalist was Hilbert [Brown,JR] |
| 9608 | There are no constructions for many highly desirable results in mathematics [Brown,JR] |
| 9645 | Constructivists say p has no value, if the value depends on Goldbach's Conjecture [Brown,JR] |
| 2392 | Properties supervene if you can't have one without the other [Chalmers] |
| 2393 | Logical supervenience is when one set of properties must be accompanied by another set [Chalmers] |
| 2394 | Natural supervenience is when one set of properties is always accompanied by another set [Chalmers] |
| 2398 | Reduction requires logical supervenience [Chalmers] |
| 9619 | David's 'Napoleon' is about something concrete and something abstract [Brown,JR] |
| 16048 | Physicalism says in any two physically indiscernible worlds the positive facts are the same [Chalmers, by Bennett,K] |
| 2401 | All facts are either physical, experiential, laws of nature, second-order final facts, or indexical facts about me [Chalmers] |
| 10173 | A nominalist might avoid abstract objects by just appealing to mereological sums [Reck/Price] |
| 16424 | Strong metaphysical necessity allows fewer possible worlds than logical necessity [Chalmers] |
| 16425 | Metaphysical necessity is a bizarre, brute and inexplicable constraint on possibilities [Chalmers] |
| 16426 | How can we know the metaphysical impossibilities; the a posteriori only concerns this world [Chalmers] |
| 13956 | Kripke is often taken to be challenging a priori insights into necessity [Chalmers] |
| 13963 | Maybe logical possibility does imply conceivability - by an ideal mind [Chalmers] |
| 2407 | One can wrongly imagine two things being non-identical even though they are the same (morning/evening star) [Chalmers] |
| 2390 | We attribute beliefs to people in order to explain their behaviour [Chalmers] |
| 2397 | 'Perception' means either an action or a mental state [Chalmers] |
| 2422 | The structure of the retina has already simplified the colour information which hits it [Chalmers] |
| 2396 | Reductive explanation is not the be-all and the end-all of explanation [Chalmers] |
| 2426 | Why are minds homogeneous and brains fine-grained? [Chalmers] |
| 2391 | Can we be aware but not conscious? [Chalmers] |
| 2412 | Can we explain behaviour without consciousness? [Chalmers] |
| 2386 | Hard Problem: why brains experience things [Chalmers] |
| 2416 | What turns awareness into consciousness? [Chalmers] |
| 2423 | Going down the scale, where would consciousness vanish? [Chalmers] |
| 2403 | Nothing in physics even suggests consciousness [Chalmers] |
| 2400 | Is intentionality just causal connections? [Chalmers] |
| 2389 | Sometimes we don't notice our pains [Chalmers] |
| 2419 | Why should qualia fade during silicon replacement? [Chalmers] |
| 2402 | It seems possible to invert qualia [Chalmers] |
| 2415 | In blindsight both qualia and intentionality are missing [Chalmers] |
| 2414 | When distracted we can totally misjudge our own experiences [Chalmers] |
| 2409 | Maybe dualist interaction is possible at the quantum level? [Chalmers] |
| 2411 | Supervenience makes interaction laws possible [Chalmers] |
| 2424 | It is odd if experience is a very recent development [Chalmers] |
| 2413 | If I can have a zombie twin, my own behaviour doesn't need consciousness [Chalmers] |
| 2417 | Does consciousness arise from fine-grained non-reductive functional organisation? [Chalmers] |
| 2428 | Maybe the whole Chinese Room understands Chinese, though the person doesn't [Chalmers] |
| 2418 | The Chinese Mind doesn't seem conscious, but then nor do brains from outside [Chalmers] |
| 2406 | H2O causes liquidity, but no one is a dualist about that [Chalmers] |
| 2405 | Perhaps consciousness is physically based, but not logically required by that base [Chalmers] |
| 2395 | Zombies imply natural but not logical supervenience [Chalmers] |
| 9318 | Phenomenal consciousness is fundamental, with no possible nonphenomenal explanation [Chalmers, by Kriegel/Williford] |
| 2404 | Nothing external shows whether a mouse is conscious [Chalmers] |
| 2429 | Temperature (etc.) is agreed to be reducible, but it is multiply realisable [Chalmers] |
| 18403 | Indexicals may not be objective, but they are a fact about the world as I see it [Chalmers] |
| 9611 | 'Abstract' nowadays means outside space and time, not concrete, not physical [Brown,JR] |
| 9609 | The older sense of 'abstract' is where 'redness' or 'group' is abstracted from particulars [Brown,JR] |
| 9640 | A term can have not only a sense and a reference, but also a 'computational role' [Brown,JR] |
| 14708 | Rationalist 2D semantics posits necessary relations between meaning, apriority, and possibility [Chalmers, by Schroeter] |
| 13958 | The 'primary intension' is non-empirical, and fixes extensions based on the actual-world reference [Chalmers] |
| 2399 | Meaning has split into primary ("watery stuff"), and secondary counterfactual meaning ("H2O") [Chalmers] |
| 13959 | The 'secondary intension' is determined by rigidifying (as H2O) the 'water' picked out in the actual world [Chalmers] |
| 13957 | Primary and secondary intensions are the a priori (actual) and a posteriori (counterfactual) aspects of meaning [Chalmers] |
| 13961 | We have 'primary' truth-conditions for the actual world, and derived 'secondary' ones for counterfactual worlds [Chalmers] |
| 13962 | Two-dimensional semantics gives a 'primary' and 'secondary' proposition for each statement [Chalmers] |
| 13960 | In two-dimensional semantics we have two aspects to truth in virtue of meaning [Chalmers] |
| 9635 | Given atomism at one end, and a finite universe at the other, there are no physical infinities [Brown,JR] |
| 16427 | Presumably God can do anything which is logically possible [Chalmers] |