121 ideas
14857 | The highest wisdom has the guise of simplicity [Nietzsche] |
14854 | Deep thinkers know that they are always wrong [Nietzsche] |
14833 | Comedy is a transition from fear to exuberance [Nietzsche] |
6267 | A culture needs to admit that knowledge is more extensive than just 'science' [Putnam] |
6272 | 'True' and 'refers' cannot be made scientically precise, but are fundamental to science [Putnam] |
6276 | 'The rug is green' might be warrantedly assertible even though the rug is not green [Putnam] |
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] |
6266 | We need the correspondence theory of truth to understand language and science [Putnam] |
6277 | Correspondence between concepts and unconceptualised reality is impossible [Putnam] |
6264 | In Tarski's definition, you understand 'true' if you accept the notions of the object language [Putnam] |
6265 | Tarski has given a correct account of the formal logic of 'true', but there is more to the concept [Putnam] |
6269 | Only Tarski has found a way to define 'true' [Putnam] |
9738 | Each line of a truth table is a model [Fitting/Mendelsohn] |
9727 | Modal logic adds □ (necessarily) and ◊ (possibly) to classical logic [Fitting/Mendelsohn] |
9726 | We let 'R' be the accessibility relation: xRy is read 'y is accessible from x' [Fitting/Mendelsohn] |
9737 | The symbol ||- is the 'forcing' relation; 'Γ ||- P' means that P is true in world Γ [Fitting/Mendelsohn] |
13136 | The prefix σ names a possible world, and σ.n names a world accessible from that one [Fitting/Mendelsohn] |
13727 | A 'constant' domain is the same for all worlds; 'varying' domains can be entirely separate [Fitting/Mendelsohn] |
9734 | Modern modal logic introduces 'accessibility', saying xRy means 'y is accessible from x' [Fitting/Mendelsohn] |
9736 | A 'model' is a frame plus specification of propositions true at worlds, written < G,R,||- > [Fitting/Mendelsohn] |
9735 | A 'frame' is a set G of possible worlds, with an accessibility relation R, written < G,R > [Fitting/Mendelsohn] |
9741 | Accessibility relations can be 'reflexive' (self-referring), 'transitive' (carries over), or 'symmetric' (mutual) [Fitting/Mendelsohn] |
13149 | S5: a) if n ◊X then kX b) if n ¬□X then k ¬X c) if n □X then k X d) if n ¬◊X then k ¬X [Fitting/Mendelsohn] |
9740 | If a proposition is possibly true in a world, it is true in some world accessible from that world [Fitting/Mendelsohn] |
9739 | If a proposition is necessarily true in a world, it is true in all worlds accessible from that world [Fitting/Mendelsohn] |
13137 | Conj: a) if σ X∧Y then σ X and σ Y b) if σ ¬(X∧Y) then σ ¬X or σ ¬Y [Fitting/Mendelsohn] |
13140 | Bicon: a)if σ(X↔Y) then σ(X→Y) and σ(Y→X) b) [not biconditional, one or other fails] [Fitting/Mendelsohn] |
13139 | Implic: a) if σ ¬(X→Y) then σ X and σ ¬Y b) if σ X→Y then σ ¬X or σ Y [Fitting/Mendelsohn] |
13143 | Universal: a) if σ ¬◊X then σ.m ¬X b) if σ □X then σ.m X [m exists] [Fitting/Mendelsohn] |
13141 | Negation: if σ ¬¬X then σ X [Fitting/Mendelsohn] |
13138 | Disj: a) if σ ¬(X∨Y) then σ ¬X and σ ¬Y b) if σ X∨Y then σ X or σ Y [Fitting/Mendelsohn] |
13142 | Existential: a) if σ ◊X then σ.n X b) if σ ¬□X then σ.n ¬X [n is new] [Fitting/Mendelsohn] |
13144 | T reflexive: a) if σ □X then σ X b) if σ ¬◊X then σ ¬X [Fitting/Mendelsohn] |
13145 | D serial: a) if σ □X then σ ◊X b) if σ ¬◊X then σ ¬□X [Fitting/Mendelsohn] |
13146 | B symmetric: a) if σ.n □X then σ X b) if σ.n ¬◊X then σ ¬X [n occurs] [Fitting/Mendelsohn] |
13147 | 4 transitive: a) if σ □X then σ.n □X b) if σ ¬◊X then σ.n ¬◊X [n occurs] [Fitting/Mendelsohn] |
13148 | 4r rev-trans: a) if σ.n □X then σ □X b) if σ.n ¬◊X then σ ¬◊X [n occurs] [Fitting/Mendelsohn] |
9742 | The system K has no accessibility conditions [Fitting/Mendelsohn] |
13114 | □P → P is not valid in D (Deontic Logic), since an obligatory action may be not performed [Fitting/Mendelsohn] |
9743 | The system D has the 'serial' conditon imposed on its accessibility relation [Fitting/Mendelsohn] |
9744 | The system T has the 'reflexive' conditon imposed on its accessibility relation [Fitting/Mendelsohn] |
9746 | The system K4 has the 'transitive' condition on its accessibility relation [Fitting/Mendelsohn] |
9745 | The system B has the 'reflexive' and 'symmetric' conditions on its accessibility relation [Fitting/Mendelsohn] |
9747 | The system S4 has the 'reflexive' and 'transitive' conditions on its accessibility relation [Fitting/Mendelsohn] |
9748 | System S5 has the 'reflexive', 'symmetric' and 'transitive' conditions on its accessibility relation [Fitting/Mendelsohn] |
9404 | Modality affects content, because P→◊P is valid, but ◊P→P isn't [Fitting/Mendelsohn] |
13112 | In epistemic logic knowers are logically omniscient, so they know that they know [Fitting/Mendelsohn] |
13111 | Read epistemic box as 'a knows/believes P' and diamond as 'for all a knows/believes, P' [Fitting/Mendelsohn] |
13113 | F: will sometime, P: was sometime, G: will always, H: was always [Fitting/Mendelsohn] |
13728 | The Barcan says nothing comes into existence; the Converse says nothing ceases; the pair imply stability [Fitting/Mendelsohn] |
13729 | The Barcan corresponds to anti-monotonicity, and the Converse to monotonicity [Fitting/Mendelsohn] |
9725 | 'Predicate abstraction' abstracts predicates from formulae, giving scope for constants and functions [Fitting/Mendelsohn] |
6280 | Realism is a theory, which explains the convergence of science and the success of language [Putnam] |
13730 | The Indiscernibility of Identicals has been a big problem for modal logic [Fitting/Mendelsohn] |
13725 | □ must be sensitive as to whether it picks out an object by essential or by contingent properties [Fitting/Mendelsohn] |
13731 | Objects retain their possible properties across worlds, so a bundle theory of them seems best [Fitting/Mendelsohn] |
13726 | Counterpart relations are neither symmetric nor transitive, so there is no logic of equality for them [Fitting/Mendelsohn] |
14858 | Being certain presumes that there are absolute truths, and means of arriving at them [Nietzsche] |
6284 | If a tautology is immune from revision, why would that make it true? [Putnam] |
14830 | Intuition only recognises what is possible, not what exists or is certain [Nietzsche] |
6273 | Knowledge depends on believing others, which must be innate, as inferences are not strong enough [Putnam] |
6274 | Empathy may not give knowledge, but it can give plausibility or right opinion [Putnam] |
17084 | You can't decide which explanations are good if you don't attend to the interest-relative aspects [Putnam] |
20378 | Just as skin hides the horrors of the body, vanity conceals the passions of the soul [Nietzsche] |
6282 | Theory of meaning presupposes theory of understanding and reference [Putnam] |
6281 | Truth conditions can't explain understanding a sentence, because that in turn needs explanation [Putnam] |
6278 | We should reject the view that truth is prior to meaning [Putnam] |
6271 | How reference is specified is not what reference is [Putnam] |
6268 | The claim that scientific terms are incommensurable can be blocked if scientific terms are not descriptions [Putnam] |
6279 | A private language could work with reference and beliefs, and wouldn't need meaning [Putnam] |
6270 | The correct translation is the one that explains the speaker's behaviour [Putnam] |
6283 | Language maps the world in many ways (because it maps onto other languages in many ways) [Putnam] |
6275 | You can't say 'most speaker's beliefs are true'; in some areas this is not so, and you can't count beliefs [Putnam] |
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] |
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] |