161 ideas
| 13466 | We are all post-Kantians, because he set the current agenda for philosophy [Hart,WD] |
| 13477 | The problems are the monuments of philosophy [Hart,WD] |
| 16395 | Kripke separated semantics from metaphysics, rather than linking them, making the latter independent [Kripke, by Stalnaker] |
| 17034 | Analyses of concepts using entirely different terms are very inclined to fail [Kripke] |
| 13515 | To study abstract problems, some knowledge of set theory is essential [Hart,WD] |
| 4955 | Some definitions aim to fix a reference rather than give a meaning [Kripke] |
| 13469 | Tarski showed how we could have a correspondence theory of truth, without using 'facts' [Hart,WD] |
| 13504 | Truth for sentences is satisfaction of formulae; for sentences, either all sequences satisfy it (true) or none do [Hart,WD] |
| 13503 | A first-order language has an infinity of T-sentences, which cannot add up to a definition of truth [Hart,WD] |
| 13500 | Conditional Proof: infer a conditional, if the consequent can be deduced from the antecedent [Hart,WD] |
| 13502 | ∃y... is read as 'There exists an individual, call it y, such that...', and not 'There exists a y such that...' [Hart,WD] |
| 10559 | Kripke's modal semantics presupposes certain facts about possible worlds [Kripke, by Zalta] |
| 13456 | Set theory articulates the concept of order (through relations) [Hart,WD] |
| 13497 | Nowadays ZFC and NBG are the set theories; types are dead, and NF is only useful for the whole universe [Hart,WD] |
| 13443 | ∈ relates across layers, while ⊆ relates within layers [Hart,WD] |
| 13442 | Without the empty set we could not form a∩b without checking that a and b meet [Hart,WD] |
| 13493 | In the modern view, foundation is the heart of the way to do set theory [Hart,WD] |
| 13495 | Foundation Axiom: an nonempty set has a member disjoint from it [Hart,WD] |
| 13462 | With the Axiom of Choice every set can be well-ordered [Hart,WD] |
| 13461 | We can choose from finite and evident sets, but not from infinite opaque ones [Hart,WD] |
| 13516 | If we accept that V=L, it seems to settle all the open questions of set theory [Hart,WD] |
| 13441 | Naïve set theory has trouble with comprehension, the claim that every predicate has an extension [Hart,WD] |
| 13494 | The iterative conception may not be necessary, and may have fixed points or infinitely descending chains [Hart,WD] |
| 13460 | 'Well-ordering' must have a least member, so it does the natural numbers but not the integers [Hart,WD] |
| 13458 | A partial ordering becomes 'total' if any two members of its field are comparable [Hart,WD] |
| 13457 | A 'partial ordering' is irreflexive and transitive; the sets are ordered, but not the subsets [Hart,WD] |
| 13490 | Von Neumann defines α<β as α∈β [Hart,WD] |
| 13481 | Maybe sets should be rethought in terms of the even more basic categories [Hart,WD] |
| 10437 | Names are rigid, making them unlike definite descriptions [Kripke, by Sainsbury] |
| 4949 | Names are rigid designators, which designate the same object in all possible worlds [Kripke] |
| 4951 | A bundle of qualities is a collection of abstractions, so it can't be a particular [Kripke] |
| 17031 | A name can still refer even if it satisfies none of its well-known descriptions [Kripke] |
| 8957 | Some references, such as 'Neptune', have to be fixed by description rather than baptism [Kripke, by Szabó] |
| 10428 | Proper names must have referents, because they are not descriptive [Kripke, by Sainsbury] |
| 4959 | A name's reference is not fixed by any marks or properties of the referent [Kripke] |
| 13506 | The universal quantifier can't really mean 'all', because there is no universal set [Hart,WD] |
| 13513 | Models are ways the world might be from a first-order point of view [Hart,WD] |
| 13505 | Model theory studies how set theory can model sets of sentences [Hart,WD] |
| 13511 | Model theory is mostly confined to first-order theories [Hart,WD] |
| 13512 | Modern model theory begins with the proof of Los's Conjecture in 1962 [Hart,WD] |
| 13496 | First-order logic is 'compact': consequences of a set are consequences of a finite subset [Hart,WD] |
| 13484 | Berry's Paradox: we succeed in referring to a number, with a term which says we can't do that [Hart,WD] |
| 13482 | The Burali-Forti paradox is a crisis for Cantor's ordinals [Hart,WD] |
| 13507 | The machinery used to solve the Liar can be rejigged to produce a new Liar [Hart,WD] |
| 13459 | The less-than relation < well-orders, and partially orders, and totally orders the ordinal numbers [Hart,WD] |
| 13463 | There are at least as many infinite cardinals as transfinite ordinals (because they will map) [Hart,WD] |
| 13491 | The axiom of infinity with separation gives a least limit ordinal ω [Hart,WD] |
| 13492 | Von Neumann's ordinals generalise into the transfinite better, because Zermelo's ω is a singleton [Hart,WD] |
| 13446 | 19th century arithmetization of analysis isolated the real numbers from geometry [Hart,WD] |
| 13509 | We can establish truths about infinite numbers by means of induction [Hart,WD] |
| 13474 | Euclid has a unique parallel, spherical geometry has none, and saddle geometry has several [Hart,WD] |
| 13471 | Mathematics makes existence claims, but philosophers usually say those are never analytic [Hart,WD] |
| 13488 | Mass words do not have plurals, or numerical adjectives, or use 'fewer' [Hart,WD] |
| 14896 | Kripke's metaphysics (essences, kinds, rigidity) blocks the slide into sociology [Kripke, by Ladyman/Ross] |
| 6504 | For physicalists, the only relations are spatial, temporal and causal [Robinson,H] |
| 6520 | If reality just has relational properties, what are its substantial ontological features? [Robinson,H] |
| 17647 | Kripke individuates objects by essential modal properties (and presupposes essentialism) [Kripke, by Putnam] |
| 16995 | Given that a table is made of molecules, could it not be molecular and still be this table? [Kripke] |
| 17047 | If we imagine this table made of ice or different wood, we are imagining a different table [Kripke] |
| 5450 | For Kripke, essence is origin; for Putnam, essence is properties; for Wiggins, essence is membership of a kind [Kripke, by Mautner] |
| 17055 | Atomic number 79 is part of the nature of the gold we know [Kripke] |
| 16997 | An essential property is true of an object in any case where it would have existed [Kripke] |
| 17045 | De re modality is an object having essential properties [Kripke] |
| 17030 | Important properties of an object need not be essential to it [Kripke] |
| 16955 | Kripke says internal structure fixes species; I say it is genetic affinity and a common descent [Kripke, by Dummett] |
| 16996 | Given that Nixon is indeed a human being, that he might not have been does not concern knowledge [Kripke] |
| 13971 | Kripke claims that some properties, only knowable posteriori, are known a priori to be essential [Kripke, by Soames] |
| 12100 | An essence is the necessary properties, derived from an intuitive identity, in origin, type and material [Kripke, by Witt] |
| 16991 | No one seems to know the identity conditions for a material object (or for people) over time [Kripke] |
| 11867 | If we lose track of origin, how do we show we are maintaining a reference? [Kripke, by Wiggins] |
| 12018 | Kripke argues, of the Queen, that parents of an organism are essentially so [Kripke, by Forbes,G] |
| 17046 | Could the actual Queen have been born of different parents? [Kripke] |
| 8274 | Socrates can't have a necessary origin, because he might have had no 'origin' [Lowe on Kripke] |
| 17036 | Identity statements can be contingent if they rely on descriptions [Kripke] |
| 17038 | If Hesperus and Phosophorus are the same, they can't possibly be different [Kripke] |
| 11880 | Kripke says his necessary a posteriori examples are known a priori to be necessary [Kripke, by Mackie,P] |
| 4797 | Instead of being regularities, maybe natural laws are the weak a posteriori necessities of Kripke [Kripke, by Psillos] |
| 17037 | Physical necessity may be necessity in the highest degree [Kripke] |
| 4728 | Kripke separates necessary and a priori, proposing necessary a posteriori and contingent a priori examples [Kripke, by O'Grady] |
| 16990 | A priori = Necessary because we imagine all worlds, and we know without looking at actuality? [Kripke] |
| 9386 | The meter is defined necessarily, but the stick being one meter long is contingent a priori [Kripke] |
| 2408 | Kripke has demonstrated that some necessary truths are only knowable a posteriori [Kripke, by Chalmers] |
| 4960 | "'Hesperus' is 'Phosphorus'" is necessarily true, if it is true, but not known a priori [Kripke] |
| 4966 | Theoretical identities are between rigid designators, and so are necessary a posteriori [Kripke] |
| 13967 | Kripke's essentialist necessary a posteriori opened the gap between conceivable and really possible [Soames on Kripke] |
| 13970 | Kripke gets to the necessary a posteriori by only allowing conceivability when combined with actuality [Kripke, by Soames] |
| 16992 | Possible worlds aren't puzzling places to learn about, but places we ourselves describe [Kripke] |
| 16993 | If we discuss what might have happened to Nixon, we stipulate that it is about Nixon [Kripke] |
| 16998 | Transworld identification is unproblematic, because we stipulate that we rigidly refer to something [Kripke] |
| 17001 | A table in some possible world should not even be identified by its essential properties [Kripke] |
| 4952 | Identification across possible worlds does not need properties, even essential ones [Kripke] |
| 7761 | Test for rigidity by inserting into the sentence 'N might not have been N' [Kripke, by Lycan] |
| 7693 | Kripke avoids difficulties of transworld identity by saying it is a decision, not a discovery [Kripke, by Jacquette] |
| 5821 | Saying that natural kinds are 'rigid designators' is the same as saying they are 'indexical' [Kripke, by Putnam] |
| 14068 | If Kripke names must still denote a thing in a non-actual situation, the statue isn't its clay [Gibbard on Kripke] |
| 10436 | A rigid expression may refer at a world to an object not existing in that world [Kripke, by Sainsbury] |
| 4953 | We do not begin with possible worlds and place objects in them; we begin with objects in the real world [Kripke] |
| 4961 | It is a necessary truth that Elizabeth II was the child of two particular parents [Kripke] |
| 16986 | That there might have been unicorns is false; we don't know the circumstances for unicorns [Kripke] |
| 6485 | When a red object is viewed, the air in between does not become red [Robinson,H] |
| 6521 | Representative realists believe that laws of phenomena will apply to the physical world [Robinson,H] |
| 6509 | Representative realists believe some properties of sense-data are shared by the objects themselves [Robinson,H] |
| 6522 | Phenomenalism can be theistic (Berkeley), or sceptical (Hume), or analytic (20th century) [Robinson,H] |
| 8259 | Kripke has breathed new life into the a priori/a posteriori distinction [Kripke, by Lowe] |
| 16989 | Rather than 'a priori truth', it is best to stick to whether some person knows it on a priori evidence [Kripke] |
| 4947 | A priori truths can be known independently of experience - but they don't have to be [Kripke] |
| 13480 | Fregean self-evidence is an intrinsic property of basic truths, rules and definitions [Hart,WD] |
| 13975 | Kripke was more successful in illuminating necessity than a priority (and their relations to analyticity) [Kripke, by Soames] |
| 17048 | Analytic judgements are a priori, even when their content is empirical [Kripke] |
| 13476 | The failure of key assumptions in geometry, mereology and set theory throw doubt on the a priori [Hart,WD] |
| 6502 | Can we reduce perception to acquisition of information, which is reduced to causation or disposition? [Robinson,H] |
| 6513 | Would someone who recovered their sight recognise felt shapes just by looking? [Robinson,H] |
| 6512 | Secondary qualities have one sensory mode, but primary qualities can have more [Robinson,H] |
| 6497 | We say objects possess no intrinsic secondary qualities because physicists don't need them [Robinson,H] |
| 6494 | If objects are not coloured, and neither are sense-contents, we are left saying that nothing is coloured [Robinson,H] |
| 6499 | Shape can be experienced in different ways, but colour and sound only one way [Robinson,H] |
| 6500 | If secondary qualities match senses, would new senses create new qualities? [Robinson,H] |
| 6484 | Most moderate empiricists adopt Locke's representative theory of perception [Robinson,H] |
| 6508 | Sense-data leads to either representative realism or phenomenalism or idealism [Robinson,H] |
| 6480 | Sense-data do not have any intrinsic intentionality [Robinson,H] |
| 6482 | For idealists and phenomenalists sense-data are in objects; representative realists say they resemble objects [Robinson,H] |
| 6505 | Sense-data are rejected because they are a veil between us and reality, leading to scepticism [Robinson,H] |
| 6506 | 'Sense redly' sounds peculiar, but 'senses redly-squarely tablely' sounds far worse [Robinson,H] |
| 6507 | Adverbialism sees the contents of sense-experience as modes, not objects [Robinson,H] |
| 6511 | If there are only 'modes' of sensing, then an object can no more be red or square than it can be proud or lazy. [Robinson,H] |
| 4948 | Intuition is the strongest possible evidence one can have about anything [Kripke] |
| 4958 | Identities like 'heat is molecule motion' are necessary (in the highest degree), not contingent [Kripke] |
| 6515 | An explanation presupposes something that is improbable unless it is explained [Robinson,H] |
| 6517 | If all possibilities are equal, order seems (a priori) to need an explanation - or does it? [Robinson,H] |
| 6481 | If intentional states are intrinsically about other things, what are their own properties? [Robinson,H] |
| 4967 | It seems logically possible to have the pain brain state without the actual pain [Kripke] |
| 7430 | Kripke assumes that mind-brain identity designates rigidly, which it doesn't [Armstrong on Kripke] |
| 6503 | Physicalism cannot allow internal intentional objects, as brain states can't be 'about' anything [Robinson,H] |
| 7867 | If consciousness could separate from brain, then it cannot be identical with brain [Kripke, by Papineau] |
| 3228 | Kripke says pain is necessarily pain, but a brain state isn't necessarily painful [Kripke, by Rey] |
| 5832 | Identity must be necessary, but pain isn't necessarily a brain state, so they aren't identical [Kripke, by Schwartz,SP] |
| 4968 | Identity theorists seem committed to no-brain-event-no-pain, and vice versa, which seems wrong [Kripke] |
| 13475 | The Fregean concept of GREEN is a function assigning true to green things, and false to the rest [Hart,WD] |
| 16394 | Kripke derives accounts of reference and proper names from assumptions about worlds and essences [Stalnaker on Kripke] |
| 17874 | Kripke has a definitional account of kinds, but not of naming [Almog on Kripke] |
| 5822 | The important cause is not between dubbing and current use, but between the item and the speaker's information [Evans on Kripke] |
| 17033 | We may refer through a causal chain, but still change what is referred to [Kripke] |
| 4689 | Kripke makes reference a largely social matter, external to the mind of the speaker [Kripke, by McGinn] |
| 17504 | Kripke's theory is important because it gives a collective account of reference [Kripke, by Putnam] |
| 17035 | We refer through the community, going back to the original referent [Kripke] |
| 16988 | Descriptive reference shows how to refer, how to identify two things, and how to challenge existence [Kripke, by PG] |
| 17029 | It can't be necessary that Aristotle had the properties commonly attributed to him [Kripke] |
| 14893 | Rigid designation creates a puzzle - why do some necessary truths appear to be contingent? [Kripke, by Macià/Garcia-Carpentiro] |
| 6519 | Locke's solidity is not matter, because that is impenetrability and hardness combined [Robinson,H] |
| 4963 | The properties that fix reference are contingent, the properties involving meaning are necessary [Kripke] |
| 17056 | Terms for natural kinds are very close to proper names [Kripke] |
| 17053 | Gold's atomic number might not be 79, but if it is, could non-79 stuff be gold? [Kripke] |
| 4964 | 'Cats are animals' has turned out to be a necessary truth [Kripke] |
| 6765 | Nominal essence may well be neither necessary nor sufficient for a natural kind [Kripke, by Bird] |
| 9387 | The scientific discovery (if correct) that gold has atomic number 79 is a necessary truth [Kripke] |
| 17054 | Scientific discoveries about gold are necessary truths [Kripke] |
| 17057 | Once we've found that heat is molecular motion, then that's what it is, in all possible worlds [Kripke] |
| 4965 | Science searches basic structures in search of essences [Kripke] |
| 17050 | Tigers may lack all the properties we originally used to identify them [Kripke] |
| 17049 | 'Tiger' designates a species, and merely looking like the species is not enough [Kripke] |
| 17051 | The original concept of 'cat' comes from paradigmatic instances [Kripke] |