81 ideas
3240 | There is more insight in fundamental perplexity about problems than in their supposed solutions [Nagel] |
3269 | If your life is to be meaningful as part of some large thing, the large thing must be meaningful [Nagel] |
3242 | Philosophy is the childhood of the intellect, and a culture can't skip it [Nagel] |
3241 | It seems mad, but the aim of philosophy is to climb outside of our own minds [Nagel] |
1489 | Modern philosophy tends to be a theory-constructing extension of science, but there is also problem-solving [Nagel] |
20989 | Views are objective if they don't rely on a person's character, social position or species [Nagel] |
22354 | Things cause perceptions, properties have other effects, hence we reach a 'view from nowhere' [Nagel, by Reiss/Sprenger] |
3248 | Realism invites scepticism because it claims to be objective [Nagel] |
13913 | The four 'perfect syllogisms' are called Barbara, Celarent, Darii and Ferio [Engelbretsen/Sayward] |
13914 | Syllogistic logic has one rule: what is affirmed/denied of wholes is affirmed/denied of their parts [Engelbretsen/Sayward] |
13915 | Syllogistic can't handle sentences with singular terms, or relational terms, or compound sentences [Engelbretsen/Sayward] |
13916 | Term logic uses expression letters and brackets, and '-' for negative terms, and '+' for compound terms [Engelbretsen/Sayward] |
13850 | In modern logic all formal validity can be characterised syntactically [Engelbretsen/Sayward] |
13849 | Classical logic rests on truth and models, where constructivist logic rests on defence and refutation [Engelbretsen/Sayward] |
10757 | Henkin semantics has a second domain of predicates and relations (in upper case) [Rossberg] |
10751 | Second-order logic needs the sets, and its consequence has epistemological problems [Rossberg] |
10759 | There are at least seven possible systems of semantics for second-order logic [Rossberg] |
10753 | Logical consequence is intuitively semantic, and captured by model theory [Rossberg] |
10752 | Γ |- S says S can be deduced from Γ; Γ |= S says a good model for Γ makes S true [Rossberg] |
13851 | Unlike most other signs, = cannot be eliminated [Engelbretsen/Sayward] |
10754 | In proof-theory, logical form is shown by the logical constants [Rossberg] |
10756 | A model is a domain, and an interpretation assigning objects, predicates, relations etc. [Rossberg] |
10758 | If models of a mathematical theory are all isomorphic, it is 'categorical', with essentially one model [Rossberg] |
10761 | Completeness can always be achieved by cunning model-design [Rossberg] |
10755 | A deductive system is only incomplete with respect to a formal semantics [Rossberg] |
13852 | Axioms are ω-incomplete if the instances are all derivable, but the universal quantification isn't [Engelbretsen/Sayward] |
4242 | Pure supervenience explains nothing, and is a sign of something fundamental we don't know [Nagel] |
3291 | Emergent properties appear at high levels of complexity, but aren't explainable by the lower levels [Nagel] |
3249 | Modern science depends on the distinction between primary and secondary qualities [Nagel] |
22429 | We achieve objectivity by dropping secondary qualities, to focus on structural primary qualities [Nagel] |
3296 | Sense-data are a false objectification of what is essentially subjective [Nagel] |
3247 | Epistemology is centrally about what we should believe, not the definition of knowledge [Nagel] |
3271 | We can't control our own beliefs [Nagel] |
3270 | Justifications come to an end when we want them to [Nagel] |
3252 | Scepticism is based on ideas which scepticism makes impossible [Nagel] |
1490 | You would have to be very morally lazy to ignore criticisms of your own culture [Nagel] |
3251 | Observed regularities are only predictable if we assume hidden necessity [Nagel] |
3295 | Inner v outer brings astonishment that we are a particular person [Nagel] |
2957 | Brain bisection suggests unity of mind isn't all-or-nothing [Nagel, by Lockwood] |
3286 | An organism is conscious if and only if there is something it is like to be that organism [Nagel] |
3285 | We may be unable to abandon personal identity, even when split-brains have undermined it [Nagel] |
3293 | If you assert that we have an ego, you can still ask if that future ego will be me [Nagel] |
3244 | Personal identity cannot be fully known a priori [Nagel] |
3245 | The question of whether a future experience will be mine presupposes personal identity [Nagel] |
3246 | I can't even conceive of my brain being split in two [Nagel] |
3292 | The most difficult problem of free will is saying what the problem is [Nagel] |
3288 | Can we describe our experiences to zombies? [Nagel] |
4883 | Nagel's title creates an impenetrable mystery, by ignoring a bat's ways that may not be "like" anything [Dennett on Nagel] |
3287 | We can't be objective about experience [Nagel] |
4989 | Physicalism should explain how subjective experience is possible, but not 'what it is like' [Kirk,R on Nagel] |
4001 | The meaning of a word contains all its possible uses as well as its actual ones [Nagel] |
6479 | Noninterference requires justification as much as interference does [Nagel] |
6450 | Morality must be motivating, and not because of pre-moral motives [Nagel] |
3284 | There is no one theory of how to act (or what to believe) [Nagel] |
3257 | Total objectivity can't see value, but it sees many people with values [Nagel] |
3265 | We don't worry about the time before we were born the way we worry about death [Nagel] |
3263 | If our own life lacks meaning, devotion to others won't give it meaning [Nagel] |
3256 | Pain doesn't have a further property of badness; it gives a reason for its avoidance [Nagel] |
3272 | Moral luck can arise in character, preconditions, actual circumstances, and outcome [Nagel] |
6447 | Game theory misses out the motivation arising from the impersonal standpoint [Nagel] |
3261 | Something may be 'rational' either because it is required or because it is acceptable [Nagel] |
3258 | If cockroaches can't think about their actions, they have no duties [Nagel] |
3282 | The general form of moral reasoning is putting yourself in other people's shoes [Nagel] |
3294 | As far as possible we should become instruments to realise what is best from an eternal point of view [Nagel] |
3254 | If we can decide how to live after stepping outside of ourselves, we have the basis of a moral theory [Nagel] |
6446 | In ethics we abstract from our identity, but not from our humanity [Nagel] |
3264 | We should see others' viewpoints, but not lose touch with our own values [Nagel] |
6477 | I can only universalise a maxim if everyone else could also universalise it [Nagel] |
3255 | We find new motives by discovering reasons for action different from our preexisting motives [Nagel] |
3262 | Utilitarianism is too demanding [Nagel] |
3268 | If a small brief life is absurd, then so is a long and large one [Nagel] |
3278 | An egalitarian system must give priority to those with the worst prospects in life [Nagel] |
6448 | A legitimate system is one accepted as both impartial and reasonably partial [Nagel] |
3275 | Equality was once opposed to aristocracy, but now it opposes public utility and individual rights [Nagel] |
3277 | In judging disputes, should we use one standard, or those of each individual? [Nagel] |
3281 | The ideal of acceptability to each individual underlies the appeal to equality [Nagel] |
3273 | Equality nowadays is seen as political, social, legal and economic [Nagel] |
3274 | Equality can either be defended as good for society, or as good for individual rights [Nagel] |
6478 | Democracy is opposed to equality, if the poor are not a majority [Nagel] |
3276 | A morality of rights is very minimal, leaving a lot of human life without restrictions or duties [Nagel] |
3290 | Given the nature of heat and of water, it is literally impossible for water not to boil at the right heat [Nagel] |