91 ideas
| 13310 | Wisdom does not lie in books, and unread people can also become wise [Seneca] |
| 13295 | Wise people escape necessity by willing it [Seneca] |
| 13317 | Philosophy aims at happiness [Seneca] |
| 13293 | What philosophy offers humanity is guidance [Seneca] |
| 13309 | That something is a necessary condition of something else doesn't mean it caused it [Seneca] |
| 13313 | Even philosophers have got bogged down in analysing tiny bits of language [Seneca] |
| 18137 | Impredicative definitions are wrong, because they change the set that is being defined? [Bostock] |
| 18122 | Classical interdefinitions of logical constants and quantifiers is impossible in intuitionism [Bostock] |
| 18114 | There is no single agreed structure for set theory [Bostock] |
| 18107 | A 'proper class' cannot be a member of anything [Bostock] |
| 18115 | We could add axioms to make sets either as small or as large as possible [Bostock] |
| 18139 | The Axiom of Choice relies on reference to sets that we are unable to describe [Bostock] |
| 18105 | Replacement enforces a 'limitation of size' test for the existence of sets [Bostock] |
| 18108 | First-order logic is not decidable: there is no test of whether any formula is valid [Bostock] |
| 18109 | The completeness of first-order logic implies its compactness [Bostock] |
| 18123 | Substitutional quantification is just standard if all objects in the domain have a name [Bostock] |
| 18120 | The Deduction Theorem is what licenses a system of natural deduction [Bostock] |
| 18125 | Berry's Paradox considers the meaning of 'The least number not named by this name' [Bostock] |
| 18101 | Each addition changes the ordinality but not the cardinality, prior to aleph-1 [Bostock] |
| 18100 | ω + 1 is a new ordinal, but its cardinality is unchanged [Bostock] |
| 18102 | A cardinal is the earliest ordinal that has that number of predecessors [Bostock] |
| 18106 | Aleph-1 is the first ordinal that exceeds aleph-0 [Bostock] |
| 18095 | Instead of by cuts or series convergence, real numbers could be defined by axioms [Bostock] |
| 18099 | The number of reals is the number of subsets of the natural numbers [Bostock] |
| 18093 | For Eudoxus cuts in rationals are unique, but not every cut makes a real number [Bostock] |
| 18110 | Infinitesimals are not actually contradictory, because they can be non-standard real numbers [Bostock] |
| 18156 | Modern axioms of geometry do not need the real numbers [Bostock] |
| 18097 | The Peano Axioms describe a unique structure [Bostock] |
| 18148 | Hume's Principle is a definition with existential claims, and won't explain numbers [Bostock] |
| 18145 | Many things will satisfy Hume's Principle, so there are many interpretations of it [Bostock] |
| 18149 | There are many criteria for the identity of numbers [Bostock] |
| 18143 | Frege makes numbers sets to solve the Caesar problem, but maybe Caesar is a set! [Bostock] |
| 18116 | Numbers can't be positions, if nothing decides what position a given number has [Bostock] |
| 18117 | Structuralism falsely assumes relations to other numbers are numbers' only properties [Bostock] |
| 18141 | Nominalism about mathematics is either reductionist, or fictionalist [Bostock] |
| 18157 | Nominalism as based on application of numbers is no good, because there are too many applications [Bostock] |
| 18150 | Actual measurement could never require the precision of the real numbers [Bostock] |
| 18158 | Ordinals are mainly used adjectively, as in 'the first', 'the second'... [Bostock] |
| 18127 | Simple type theory has 'levels', but ramified type theory has 'orders' [Bostock] |
| 18144 | Neo-logicists agree that HP introduces number, but also claim that it suffices for the job [Bostock] |
| 18147 | Neo-logicists meet the Caesar problem by saying Hume's Principle is unique to number [Bostock] |
| 18146 | If Hume's Principle is the whole story, that implies structuralism [Bostock] |
| 18129 | Many crucial logicist definitions are in fact impredicative [Bostock] |
| 18111 | Treating numbers as objects doesn't seem like logic, since arithmetic fixes their totality [Bostock] |
| 18159 | Higher cardinalities in sets are just fairy stories [Bostock] |
| 18155 | A fairy tale may give predictions, but only a true theory can give explanations [Bostock] |
| 18140 | The best version of conceptualism is predicativism [Bostock] |
| 18138 | Conceptualism fails to grasp mathematical properties, infinity, and objective truth values [Bostock] |
| 18131 | If abstracta only exist if they are expressible, there can only be denumerably many of them [Bostock] |
| 18134 | Predicativism makes theories of huge cardinals impossible [Bostock] |
| 18135 | If mathematics rests on science, predicativism may be the best approach [Bostock] |
| 18136 | If we can only think of what we can describe, predicativism may be implied [Bostock] |
| 18133 | The usual definitions of identity and of natural numbers are impredicative [Bostock] |
| 18132 | The predicativity restriction makes a difference with the real numbers [Bostock] |
| 13297 | To the four causes Plato adds a fifth, the idea which guided the event [Seneca] |
| 2181 | It is an absurd Kantian idea that at the limit rationality and freedom coincide [Williams,B] |
| 2176 | There is only a problem of free will if you think the notion of 'voluntary' can be metaphysically deepened [Williams,B] |
| 13307 | If everything can be measured, try measuring the size of a man's soul [Seneca] |
| 21399 | Referring to a person, and speaking about him, are very different [Seneca] |
| 18121 | In logic a proposition means the same when it is and when it is not asserted [Bostock] |
| 4317 | We judge weakness of will by an assessment after the event is concluded [Williams,B, by Cottingham] |
| 2174 | Responsibility involves cause, intention, state of mind, and response after the event [Williams,B] |
| 2178 | In bad actions, guilt points towards victims, and shame to the agent [Williams,B] |
| 13325 | Trouble in life comes from copying other people, which is following convention instead of reason [Seneca] |
| 22239 | Humans acquired the concept of virtue from an analogy with bodily health and strength [Seneca, by Allen] |
| 13294 | We know death, which is like before birth; ceasing to be and never beginning are the same [Seneca] |
| 13299 | Living is nothing wonderful; what matters is to die well [Seneca] |
| 13300 | It is as silly to lament ceasing to be as to lament not having lived in the remote past [Seneca] |
| 13321 | Is anything sweeter than valuing yourself more when you find you are loved? [Seneca] |
| 13292 | Selfishness does not produce happiness; to live for yourself, live for others [Seneca] |
| 13303 | A man is as unhappy as he has convinced himself he is [Seneca] |
| 13302 | Life is like a play - it is the quality that matters, not the length [Seneca] |
| 13301 | We are scared of death - except when we are immersed in pleasure! [Seneca] |
| 13323 | The whole point of pleasure-seeking is novelty, and abandoning established ways [Seneca] |
| 2169 | Greek moral progress came when 'virtue' was freed from social status [Williams,B] |
| 13318 | Nature doesn't give us virtue; we must unremittingly pursue it, as a training and an art [Seneca] |
| 13324 | Living contrary to nature is like rowing against the stream [Seneca] |
| 13305 | Character is ruined by not looking back over our pasts, since the future rests on the past [Seneca] |
| 13308 | It's no good winning lots of fights, if you are then conquered by your own temper [Seneca] |
| 13312 | Excessive curiosity is a form of intemperance [Seneca] |
| 2172 | The modern idea of duty is unknown in archaic Greece [Williams,B] |
| 2179 | If the moral self is seen as characterless, then other people have a very limited role in our moral lives [Williams,B] |
| 2180 | If reason cannot lead people to good, we must hope they have an internal voice [Williams,B] |
| 13315 | To govern used to mean to serve, not to rule; rulers did not test their powers over those who bestowed it [Seneca] |
| 13290 | One joy of learning is making teaching possible [Seneca] |
| 13322 | Both teachers and pupils should aim at one thing - the improvement of the pupil [Seneca] |
| 13298 | Suicide may be appropriate even when it is not urgent, if there are few reasons against it [Seneca] |
| 13319 | If we control our own death, no one has power over us [Seneca] |
| 13320 | Sometimes we have a duty not to commit suicide, for those we love [Seneca] |
| 13311 | Does time exist on its own? Did anything precede it? Did it pre-exist the cosmos? [Seneca] |
| 2175 | There is a problem of evil only if you expect the world to be good [Williams,B] |