105 ideas
| 14857 | The highest wisdom has the guise of simplicity [Nietzsche] |
| 13466 | We are all post-Kantians, because he set the current agenda for philosophy [Hart,WD] |
| 9777 | Kant was the first philosopher [Zizek] |
| 9778 | There is no dialogue in philosophy [Zizek] |
| 9779 | Philosophy is transcendental questioning (not supporting science or constructing ontology) [Zizek] |
| 13477 | The problems are the monuments of philosophy [Hart,WD] |
| 14854 | Deep thinkers know that they are always wrong [Nietzsche] |
| 14833 | Comedy is a transition from fear to exuberance [Nietzsche] |
| 13515 | To study abstract problems, some knowledge of set theory is essential [Hart,WD] |
| 14853 | Truth finds fewest champions not when it is dangerous, but when it is boring [Nietzsche] |
| 24075 | Convictions, more than lies, are the great enemy of truth [Nietzsche] |
| 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] |
| 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] |
| 13461 | We can choose from finite and evident sets, but not from infinite opaque ones [Hart,WD] |
| 13462 | With the Axiom of Choice every set can be well-ordered [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] |
| 13457 | A 'partial ordering' is irreflexive and transitive; the sets are ordered, but not the subsets [Hart,WD] |
| 13458 | A partial ordering becomes 'total' if any two members of its field are comparable [Hart,WD] |
| 13460 | 'Well-ordering' must have a least member, so it does the natural numbers but not the integers [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] |
| 13506 | The universal quantifier can't really mean 'all', because there is no universal set [Hart,WD] |
| 13512 | Modern model theory begins with the proof of Los's Conjecture in 1962 [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] |
| 13513 | Models are ways the world might be from a first-order point of view [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] |
| 13491 | The axiom of infinity with separation gives a least limit ordinal ω [Hart,WD] |
| 13463 | There are at least as many infinite cardinals as transfinite ordinals (because they will map) [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] |
| 14858 | Being certain presumes that there are absolute truths, and means of arriving at them [Nietzsche] |
| 13480 | Fregean self-evidence is an intrinsic property of basic truths, rules and definitions [Hart,WD] |
| 13476 | The failure of key assumptions in geometry, mereology and set theory throw doubt on the a priori [Hart,WD] |
| 14830 | Intuition only recognises what is possible, not what exists or is certain [Nietzsche] |
| 9780 | Consciousness is a malfunction of evolution [Zizek] |
| 20378 | Just as skin hides the horrors of the body, vanity conceals the passions of the soul [Nietzsche] |
| 13475 | The Fregean concept of GREEN is a function assigning true to green things, and false to the rest [Hart,WD] |
| 14820 | People always do what they think is right, according to the degree of their intellect [Nietzsche] |
| 14856 | Our judgment seems to cause our nature, but actually judgment arises from our nature [Nietzsche] |
| 14842 | Why are the strong tastes of other people so contagious? [Nietzsche] |
| 14835 | Artists are not especially passionate, but they pretend to be [Nietzsche] |
| 22473 | Nietzsche said the will doesn't exist, so it can't ground moral responsibility [Nietzsche, by Foot] |
| 14807 | The history of morality rests on an error called 'responsibility', which rests on an error called 'free will' [Nietzsche] |
| 14823 | Ceasing to believe in human responsibility is bitter, if you had based the nobility of humanity on it [Nietzsche] |
| 14824 | It is absurd to blame nature and necessity; we should no more praise actions than we praise plants or artworks [Nietzsche] |
| 14812 | Intellect is tied to morality, because it requires good memory and powerful imagination [Nietzsche] |
| 14810 | Originally it was the rulers who requited good for good and evil for evil who were called 'good' [Nietzsche] |
| 9781 | Tolerance and love are strategies to avoid encountering our neighbours [Zizek] |
| 14831 | No one has ever done anything that was entirely for other people [Nietzsche] |
| 14855 | Simultaneous love and respect are impossible; love has no separation or rank, but respect admits power [Nietzsche] |
| 14815 | We get enormous pleasure from tales of noble actions [Nietzsche] |
| 14849 | We can only achieve happy moments, not happy eras [Nietzsche] |
| 14818 | First morality is force, then custom, then acceptance, then instinct, then a pleasure - and finally 'virtue' [Nietzsche] |
| 20103 | You are mastered by your own virtues, but you must master them, and turn them into tools [Nietzsche] |
| 14817 | The 'good' man does the moral thing as if by nature, easily and gladly, after a long inheritance [Nietzsche] |
| 14809 | All societies of good men give a priority to gratitude [Nietzsche] |
| 14816 | Justice (fairness) originates among roughly equal powers (as the Melian dialogues show) [Nietzsche] |
| 20112 | Pity consoles those who suffer, because they see that they still have the power to hurt [Nietzsche] |
| 14821 | Apart from philosophers, most people rightly have a low estimate of pity [Nietzsche] |
| 14841 | Many people are better at having good friends than being a good friend [Nietzsche] |
| 14843 | Women can be friends with men, but only some physical antipathy will maintain it [Nietzsche] |
| 14811 | In Homer it is the contemptible person, not the harmful person, who is bad [Nietzsche] |
| 20111 | We could live more naturally, relishing the spectacle, and not thinking we are special [Nietzsche] |
| 14844 | People do not experience boredom if they have never learned to work properly [Nietzsche] |
| 14808 | Over huge periods of time human character would change endlessly [Nietzsche] |
| 14822 | If self-defence is moral, then so are most expressions of 'immoral' egoism [Nietzsche] |
| 14838 | The state aims to protect individuals from one another [Nietzsche] |
| 14852 | Culture cannot do without passions and vices [Nietzsche] |
| 14846 | If we want the good life for the greatest number, we must let them decide on the good life [Nietzsche] |
| 14819 | Slavery cannot be judged by our standards, because the sense of justice was then less developed [Nietzsche] |
| 14847 | Laws that are well thought out, or laws that are easy to understand? [Nietzsche] |
| 14814 | Execution is worse than murder, because we are using the victim, and really we are the guilty [Nietzsche] |
| 14836 | People will enthusiastically pursue an unwanted war, once sacrifices have been made [Nietzsche] |
| 14845 | Don't crush girls with dull Gymnasium education, the way we have crushed boys! [Nietzsche] |
| 14848 | Education in large states is mediocre, like cooking in large kitchens [Nietzsche] |
| 14839 | Interest in education gains strength when we lose interest in God [Nietzsche] |
| 14834 | Teachers only gather knowledge for their pupils, and can't be serious about themselves [Nietzsche] |
| 14825 | In religious thought nature is a complex of arbitrary acts by conscious beings [Nietzsche] |
| 14826 | Modern man wants laws of nature in order to submit to them [Nietzsche] |
| 14827 | The Greeks saw the gods not as their masters, but as idealised versions of themselves [Nietzsche] |
| 14813 | Science rejecting the teaching of Christianity in favour of Epicurus shows the superiority of the latter [Nietzsche] |
| 14832 | The Sermon on the Mount is vanity - praying to one part of oneself, and demonising the rest [Nietzsche] |
| 14850 | Christ was the noblest human being [Nietzsche] |
| 14837 | Christ seems warm hearted, and suppressed intellect in favour of the intellectually weak [Nietzsche] |
| 14828 | Religion is tempting if your life is boring, but you can't therefore impose it on the busy people [Nietzsche] |