147 ideas
21916 | Philosophers can't be religious, and don't need to be; philosophy is perilous but free [Schopenhauer] |
4171 | Philosophy considers only the universal, in nature as everywhere else [Schopenhauer] |
4186 | Everyone is conscious of all philosophical truths, but philosophers bring them to conceptual awareness [Schopenhauer] |
12171 | Absurdity is incongruity between correct and false points of view [Schopenhauer] |
21366 | Metaphysics must understand the world thoroughly, as a principal source of knowledge [Schopenhauer] |
21474 | Metaphysics studies the inexplicable ends of explanation [Schopenhauer] |
16325 | Analysis rests on natural language, but its ideal is a framework which revises language [Halbach] |
21918 | Sufficient Reason can't be proved, because all proof presupposes it [Schopenhauer, by Lewis,PB] |
4187 | 'There is nothing without a reason why it should be rather than not be' (a generalisation of 'Why?') [Schopenhauer] |
16292 | An explicit definition enables the elimination of what is defined [Halbach] |
16307 | Don't trust analogies; they are no more than a guideline [Halbach] |
16330 | Truth-value 'gluts' allow two truth values together; 'gaps' give a partial conception of truth [Halbach] |
16339 | Truth axioms prove objects exist, so truth doesn't seem to be a logical notion [Halbach] |
16324 | Any definition of truth requires a metalanguage [Halbach] |
15647 | Truth definitions don't produce a good theory, because they go beyond your current language [Halbach] |
16293 | Traditional definitions of truth often make it more obscure, rather than less [Halbach] |
16301 | If people have big doubts about truth, a definition might give it more credibility [Halbach] |
15649 | In semantic theories of truth, the predicate is in an object-language, and the definition in a metalanguage [Halbach] |
16297 | Semantic theories avoid Tarski's Theorem by sticking to a sublanguage [Halbach] |
16337 | Disquotational truth theories are short of deductive power [Halbach] |
15650 | Axiomatic theories of truth need a weak logical framework, and not a strong metatheory [Halbach] |
16322 | CT proves PA consistent, which PA can't do on its own, so CT is not conservative over PA [Halbach] |
15654 | If truth is defined it can be eliminated, whereas axiomatic truth has various commitments [Halbach] |
16294 | Axiomatic truth doesn't presuppose a truth-definition, though it could admit it at a later stage [Halbach] |
16326 | The main semantic theories of truth are Kripke's theory, and revisions semantics [Halbach] |
16311 | To axiomatise Tarski's truth definition, we need a binary predicate for his 'satisfaction' [Halbach] |
16318 | Compositional Truth CT has the truth of a sentence depending of the semantic values of its constituents [Halbach] |
16299 | Gödel numbering means a theory of truth can use Peano Arithmetic as its base theory [Halbach] |
16340 | Truth axioms need a base theory, because that is where truth issues arise [Halbach] |
16305 | We know a complete axiomatisation of truth is not feasible [Halbach] |
16313 | A theory is 'conservative' if it adds no new theorems to its base theory [Halbach, by PG] |
16315 | The Tarski Biconditional theory TB is Peano Arithmetic, plus truth, plus all Tarski bi-conditionals [Halbach] |
16314 | Theories of truth are 'typed' (truth can't apply to sentences containing 'true'), or 'type-free' [Halbach] |
15655 | Should axiomatic truth be 'conservative' - not proving anything apart from implications of the axioms? [Halbach] |
15648 | Instead of a truth definition, add a primitive truth predicate, and axioms for how it works [Halbach] |
16327 | Friedman-Sheard is type-free Compositional Truth, with two inference rules for truth [Halbach] |
16329 | Kripke-Feferman theory KF axiomatises Kripke fixed-points, with Strong Kleene logic with gluts [Halbach] |
16332 | The KF theory is useful, but it is not a theory containing its own truth predicate [Halbach] |
16331 | The KF is much stronger deductively than FS, which relies on classical truth [Halbach] |
16319 | Compositional Truth CT proves generalisations, so is preferred in discussions of deflationism [Halbach] |
16320 | Some say deflationism is axioms which are conservative over the base theory [Halbach] |
15656 | Deflationists say truth merely serves to express infinite conjunctions [Halbach] |
16338 | Deflationism says truth is a disquotation device to express generalisations, adding no new knowledge [Halbach] |
16317 | The main problem for deflationists is they can express generalisations, but not prove them [Halbach] |
16316 | Deflationists say truth is just for expressing infinite conjunctions or generalisations [Halbach] |
16335 | In Strong Kleene logic a disjunction just needs one disjunct to be true [Halbach] |
16334 | In Weak Kleene logic there are 'gaps', neither true nor false if one component lacks a truth value [Halbach] |
15657 | To prove the consistency of set theory, we must go beyond set theory [Halbach] |
16309 | Every attempt at formal rigour uses some set theory [Halbach] |
16333 | The underestimated costs of giving up classical logic are found in mathematical reasoning [Halbach] |
15652 | We can use truth instead of ontologically loaded second-order comprehension assumptions about properties [Halbach] |
15651 | Instead of saying x has a property, we can say a formula is true of x - as long as we have 'true' [Halbach] |
16310 | A theory is some formulae and all of their consequences [Halbach] |
16342 | You cannot just say all of Peano arithmetic is true, as 'true' isn't part of the system [Halbach] |
16341 | Normally we only endorse a theory if we believe it to be sound [Halbach] |
16344 | Soundness must involve truth; the soundness of PA certainly needs it [Halbach] |
16347 | Many new paradoxes may await us when we study interactions between frameworks [Halbach] |
16336 | The liar paradox applies truth to a negated truth (but the conditional will serve equally) [Halbach] |
16321 | The compactness theorem can prove nonstandard models of PA [Halbach] |
16343 | The global reflection principle seems to express the soundness of Peano Arithmetic [Halbach] |
16312 | To reduce PA to ZF, we represent the non-negative integers with von Neumann ordinals [Halbach] |
16308 | Set theory was liberated early from types, and recent truth-theories are exploring type-free [Halbach] |
4168 | Matter and intellect are inseparable correlatives which only exist relatively, and for each other [Schopenhauer] |
16345 | That Peano arithmetic is interpretable in ZF set theory is taken by philosophers as a reduction [Halbach] |
21470 | For me the objective thing-in-itself is the will [Schopenhauer] |
21926 | Schopenhauer, unlike other idealists, says reality is irrational [Schopenhauer, by Lewis,PB] |
4167 | The knowing subject and the crude matter of the world are both in themselves unknowable [Schopenhauer] |
21920 | No need for a priori categories, since sufficient reason shows the interrelations [Schopenhauer, by Lewis,PB] |
16346 | Maybe necessity is a predicate, not the usual operator, to make it more like truth [Halbach] |
21362 | Necessity is physical, logical, mathematical or moral [Schopenhauer, by Janaway] |
4192 | All necessity arises from causation, which is conditioned; there is no absolute or unconditioned necessity [Schopenhauer] |
4190 | All understanding is an immediate apprehension of the causal relation [Schopenhauer] |
21479 | Knowledge is not power! Ignorant people possess supreme authority [Schopenhauer] |
4165 | Descartes found the true beginning of philosophy with the Cogito, in the consciousness of the individual [Schopenhauer] |
21361 | For Schopenhauer, material things would not exist without the mind [Schopenhauer, by Janaway] |
21923 | Schopenhauer can't use force/energy instead of 'will', because he is not a materialist [Lewis,PB on Schopenhauer] |
4162 | The world only exists in relation to something else, as an idea of the one who conceives it [Schopenhauer] |
21922 | We know reality because we know our own bodies and actions [Schopenhauer] |
21913 | Kant rightly separates appearance and thing-in-itself [Schopenhauer] |
21919 | Object for a subject and representation are the same thing [Schopenhauer] |
21476 | A priori propositions are those we could never be seriously motivated to challenge [Schopenhauer] |
4164 | Direct feeling of the senses are merely data; perception of the world comes with understanding causes [Schopenhauer] |
4163 | All perception is intellectual [Schopenhauer] |
21473 | All knowledge and explanation rests on the inexplicable [Schopenhauer] |
21917 | The four explanations: objects by causes, concepts by ground, maths by spacetime, ethics by motive [Schopenhauer, by Lewis,PB] |
4166 | A consciousness without an object is no consciousness [Schopenhauer] |
21369 | We have hidden and unadmitted desires and fears, suppressed because of vanity [Schopenhauer] |
21478 | Half our thinking is unconscious, and we reach conclusions while unaware of premises [Schopenhauer] |
4191 | What we know in ourselves is not a knower but a will [Schopenhauer] |
21367 | I know both aspects of my body, as representation, and as will [Schopenhauer] |
21368 | The knot of the world is the use of 'I' to refer to both willing and knowing [Schopenhauer] |
4175 | It is as perverse to resent our individuality being replaced by others, as to resent the body renewing itself [Schopenhauer] |
4176 | We all regard ourselves a priori as free, but see from experience that character and motive compel us [Schopenhauer] |
21477 | We don't control our own thinking [Schopenhauer] |
4170 | Man's actions are not free, because they follow strictly from impact of motive on character [Schopenhauer] |
21921 | Concepts are abstracted from perceptions [Schopenhauer, by Lewis,PB] |
21475 | All of our concepts are borrowed from perceptual knowledge [Schopenhauer] |
16298 | We need propositions to ascribe the same beliefs to people with different languages [Halbach] |
4169 | Every true act of will is also at once and without exception a movement of the body [Schopenhauer] |
7187 | Schopenhauer was caught in Christian ideals, because he didn't deify his 'will' [Nietzsche on Schopenhauer] |
21365 | Only the will is thing-in-itself, seen both in blind nature and in human action [Schopenhauer] |
21924 | As the subject of willing I am wretched, but absorption in knowledge is bliss [Schopenhauer] |
4173 | If we were essentially intellect rather than will, our moral worth would depend on imagined motives [Schopenhauer] |
21363 | Motivation is causality seen from within [Schopenhauer] |
21372 | Aesthetics concerns how we can take pleasure in an object, with no reference to the will [Schopenhauer] |
21370 | Schopenhauer is a chief proponent of aesthetic experience as 'disinterested' [Schopenhauer, by Janaway] |
4182 | A principal pleasure of the beautiful is that it momentarily silences the will [Schopenhauer] |
21488 | The beautiful is a perception of Plato's Forms, which eliminates the will [Schopenhauer] |
21928 | The Sublime fights for will-less knowing, when faced with a beautiful threat to humanity [Schopenhauer, by Lewis,PB] |
21927 | Schopenhauer emphasises Ideas in art, unlike most romantics [Schopenhauer, by Lewis,PB] |
8116 | The will-less contemplation of art brings a liberation from selfhood [Schopenhauer, by Gardner] |
4174 | Man is more beautiful than anything else, and the loftiest purpose of art is to reveal his nature [Schopenhauer] |
21380 | The only aim of our existence is to grasp that non-existence would be better [Schopenhauer] |
21374 | We should no more expect ethical theory to produce good people than aesthetics to produce artists [Schopenhauer] |
21378 | We clearly feel responsible for our deeds, because we are quite certain that we did them [Schopenhauer] |
21375 | Reason can be vicious, and great crimes have to be rational [Schopenhauer] |
21915 | To deduce morality from reason is blasphemy, because it is holy, and far above reason [Schopenhauer] |
21483 | Man is essentially a dreadful wild animal [Schopenhauer] |
21379 | Man's three basic ethical incentives are egoism, malice and compassion [Schopenhauer] |
4181 | Every good is essentially relative, for it has its essential nature only in its relation to a desiring will [Schopenhauer] |
5649 | Will casts aside each of its temporary fulfilments, so human life has no ultimate aim [Schopenhauer, by Scruton] |
4177 | Most people would probably choose non-existence at the end of their life, rather than relive the whole thing [Schopenhauer] |
4185 | Altruistic people make less distinction than usual between themselves and others [Schopenhauer] |
4183 | Only self-love can motivate morality, but that also makes it worthless [Schopenhauer] |
4172 | Happiness is the swift movement from desire to satisfaction, and then again on to desire [Schopenhauer] |
21371 | We can never attain happiness while our will is pursuing desires [Schopenhauer] |
21466 | Pleasure is weaker, and pain stronger, than we expect [Schopenhauer] |
4184 | Virtue must spring from an intuitive recognition that other people are essentially like us [Schopenhauer] |
21484 | A man's character can be learned from a single characteristic action [Schopenhauer] |
21482 | The five Chinese virtues: pity, justice, politeness, wisdom, honesty [Schopenhauer] |
21481 | Buddhists wisely start with the cardinal vices [Schopenhauer] |
21480 | Boredom is only felt by those clever enough to need activity [Schopenhauer] |
21469 | Human life is a mistake, shown by boredom, which is direct awareness of the fact [Schopenhauer] |
21485 | The state only exists to defend citizens, from exterior threats, and from one another [Schopenhauer] |
21486 | Poverty and slavery are virtually two words for the same thing [Schopenhauer] |
21487 | The freedom of the press to sell poison outweighs its usefulness [Schopenhauer] |
21471 | If suicide was quick and easy, most people would have done it by now [Schopenhauer] |
21467 | Would humanity still exist if sex wasn't both desired and pleasurable? [Schopenhauer] |
21376 | Philosophy treats animals as exploitable things, ignoring the significance of their lives [Schopenhauer] |
1868 | The world was made as much for animals as for man [Celsus] |
4179 | The essence of nature is the will to life itself [Schopenhauer] |
4189 | Time may be defined as the possibility of mutually exclusive conditions of the same thing [Schopenhauer] |
4178 | Christianity is a pessimistic religion, in which the world is equated with evil [Schopenhauer] |
1867 | Christians presented Jesus as a new kind of logos to oppose that of the philosophers [Celsus] |
4180 | Religion is the mythical clothing of the truth which is inaccessible to the crude human intellect [Schopenhauer] |
21472 | Only religion introduces serious issues to uneducated people [Schopenhauer] |
21468 | The Creator created the possibilities for worlds, so should have made a better one than this possible [Schopenhauer] |