189 ideas
22115 | Wise people should contemplate and discuss the truth, and fight against falsehood [Aquinas] |
22101 | Philosophy aims to know the truth about the way things are [Aquinas] |
19199 | Some say metaphysics is a highly generalised empirical study of objects [Tarski] |
19193 | Disputes that fail to use precise scientific terminology are all meaningless [Tarski] |
1848 | We are coerced into assent to a truth by reason's violence [Aquinas] |
1858 | The mind is compelled by necessary truths, but not by contingent truths [Aquinas] |
21267 | Supposing many principles is superfluous if a few will do it [Aquinas] |
22102 | Arguing with opponents uncovers truths, and restrains falsehoods [Aquinas] |
19179 | For a definition we need the words or concepts used, the rules, and the structure of the language [Tarski] |
13070 | If definitions must be general, and general terms can't individuate, then Socrates can't be defined [Aquinas, by Cover/O'Leary-Hawthorne] |
11197 | The definitions expressing identity are used to sort things [Aquinas] |
23176 | Truth is universal, but knowledge of it is not [Aquinas] |
20621 | Types of lying: Speak lies, intend lies, intend deception, aim at deceptive goal? [Aquinas, by Tuckness/Wolf] |
16295 | Tarski proved that truth cannot be defined from within a given theory [Tarski, by Halbach] |
15342 | Tarski proved that any reasonably expressive language suffers from the liar paradox [Tarski, by Horsten] |
19069 | 'True sentence' has no use consistent with logic and ordinary language, so definition seems hopeless [Tarski] |
10153 | In everyday language, truth seems indefinable, inconsistent, and illogical [Tarski] |
19178 | Definitions of truth should not introduce a new version of the concept, but capture the old one [Tarski] |
19177 | A definition of truth should be materially adequate and formally correct [Tarski] |
19186 | A rigorous definition of truth is only possible in an exactly specified language [Tarski] |
19194 | We may eventually need to split the word 'true' into several less ambiguous terms [Tarski] |
1852 | For the mind Good is one truth among many, and Truth is one good among many [Aquinas] |
21248 | If the existence of truth is denied, the 'Truth does not exist' must be true! [Aquinas] |
22104 | Truth is the conformity of being to intellect [Aquinas] |
16296 | Tarski's Theorem renders any precise version of correspondence impossible [Tarski, by Halbach] |
10672 | Tarskian semantics says that a sentence is true iff it is satisfied by every sequence [Tarski, by Hossack] |
13338 | '"It is snowing" is true if and only if it is snowing' is a partial definition of the concept of truth [Tarski] |
15339 | Tarski gave up on the essence of truth, and asked how truth is used, or how it functions [Tarski, by Horsten] |
16302 | Tarski did not just aim at a definition; he also offered an adequacy criterion for any truth definition [Tarski, by Halbach] |
19135 | Tarski enumerates cases of truth, so it can't be applied to new words or languages [Davidson on Tarski] |
19138 | Tarski define truths by giving the extension of the predicate, rather than the meaning [Davidson on Tarski] |
4699 | Tarski made truth relative, by only defining truth within some given artificial language [Tarski, by O'Grady] |
19324 | Tarski has to avoid stating how truths relate to states of affairs [Kirkham on Tarski] |
19180 | It is convenient to attach 'true' to sentences, and hence the language must be specified [Tarski] |
19181 | In the classical concept of truth, 'snow is white' is true if snow is white [Tarski] |
19196 | Scheme (T) is not a definition of truth [Tarski] |
19183 | Each interpreted T-sentence is a partial definition of truth; the whole definition is their conjunction [Tarski] |
19182 | Use 'true' so that all T-sentences can be asserted, and the definition will then be 'adequate' [Tarski] |
19198 | We don't give conditions for asserting 'snow is white'; just that assertion implies 'snow is white' is true [Tarski] |
15410 | Truth only applies to closed formulas, but we need satisfaction of open formulas to define it [Burgess on Tarski] |
18811 | Tarski uses sentential functions; truly assigning the objects to variables is what satisfies them [Tarski, by Rumfitt] |
15365 | We can define the truth predicate using 'true of' (satisfaction) for variables and some objects [Tarski, by Horsten] |
19314 | For physicalism, reduce truth to satisfaction, then define satisfaction as physical-plus-logic [Tarski, by Kirkham] |
19316 | Insight: don't use truth, use a property which can be compositional in complex quantified sentence [Tarski, by Kirkham] |
19175 | Tarski gave axioms for satisfaction, then derived its explicit definition, which led to defining truth [Tarski, by Davidson] |
19184 | The best truth definition involves other semantic notions, like satisfaction (relating terms and objects) [Tarski] |
19191 | Specify satisfaction for simple sentences, then compounds; true sentences are satisfied by all objects [Tarski] |
19188 | We can't use a semantically closed language, or ditch our logic, so a meta-language is needed [Tarski] |
19189 | The metalanguage must contain the object language, logic, and defined semantics [Tarski] |
19134 | Tarski defined truth for particular languages, but didn't define it across languages [Davidson on Tarski] |
16304 | Tarski didn't capture the notion of an adequate truth definition, as Convention T won't prove non-contradiction [Halbach on Tarski] |
2571 | Tarski says that his semantic theory of truth is completely neutral about all metaphysics [Tarski, by Haack] |
10821 | Physicalists should explain reference nonsemantically, rather than getting rid of it [Tarski, by Field,H] |
10822 | A physicalist account must add primitive reference to Tarski's theory [Field,H on Tarski] |
10824 | If listing equivalences is a reduction of truth, witchcraft is just a list of witch-victim pairs [Field,H on Tarski] |
16303 | Tarski made truth respectable, by proving that it could be defined [Tarski, by Halbach] |
10969 | Tarski had a theory of truth, and a theory of theories of truth [Tarski, by Read] |
17746 | Tarski's 'truth' is a precise relation between the language and its semantics [Tarski, by Walicki] |
10904 | Tarskian truth neglects the atomic sentences [Mulligan/Simons/Smith on Tarski] |
15322 | Tarski's had the first axiomatic theory of truth that was minimally adequate [Tarski, by Horsten] |
16306 | Tarski defined truth, but an axiomatisation can be extracted from his inductive clauses [Tarski, by Halbach] |
19141 | Tarski thought axiomatic truth was too contingent, and in danger of inconsistencies [Tarski, by Davidson] |
19190 | We need an undefined term 'true' in the meta-language, specified by axioms [Tarski] |
19197 | Truth can't be eliminated from universal claims, or from particular unspecified claims [Tarski] |
19185 | Semantics is a very modest discipline which solves no real problems [Tarski] |
19195 | Truth tables give prior conditions for logic, but are outside the system, and not definitions [Tarski] |
10152 | Set theory and logic are fairy tales, but still worth studying [Tarski] |
10048 | There is no clear boundary between the logical and the non-logical [Tarski] |
13337 | A language: primitive terms, then definition rules, then sentences, then axioms, and finally inference rules [Tarski] |
23173 | If a syllogism admits one absurdity, others must follow [Aquinas] |
18812 | Split out the logical vocabulary, make an assignment to the rest. It's logical if premises and conclusion match [Tarski, by Rumfitt] |
10694 | Logical consequence is when in any model in which the premises are true, the conclusion is true [Tarski, by Beall/Restall] |
10479 | Logical consequence: true premises give true conclusions under all interpretations [Tarski, by Hodges,W] |
13344 | X follows from sentences K iff every model of K also models X [Tarski] |
19192 | The truth definition proves semantic contradiction and excluded middle laws (not the logic laws) [Tarski] |
18759 | Identity is invariant under arbitrary permutations, so it seems to be a logical term [Tarski, by McGee] |
10823 | A name denotes an object if the object satisfies a particular sentential function [Tarski] |
18756 | Tarski built a compositional semantics for predicate logic, from dependent satisfactions [Tarski, by McGee] |
19313 | Tarksi invented the first semantics for predicate logic, using this conception of truth [Tarski, by Kirkham] |
13335 | Semantics is the concepts of connections of language to reality, such as denotation, definition and truth [Tarski] |
13336 | A language containing its own semantics is inconsistent - but we can use a second language [Tarski] |
13339 | A sentence is satisfied when we can assert the sentence when the variables are assigned [Tarski] |
13340 | Satisfaction is the easiest semantical concept to define, and the others will reduce to it [Tarski] |
16323 | The object language/ metalanguage distinction is the basis of model theory [Tarski, by Halbach] |
13343 | A 'model' is a sequence of objects which satisfies a complete set of sentential functions [Tarski] |
13341 | Using the definition of truth, we can prove theories consistent within sound logics [Tarski] |
8940 | Tarski avoids the Liar Paradox, because truth cannot be asserted within the object language [Tarski, by Fisher] |
19187 | The Liar makes us assert a false sentence, so it must be taken seriously [Tarski] |
10157 | Tarski improved Hilbert's geometry axioms, and without set-theory [Tarski, by Feferman/Feferman] |
10154 | Tarski's theory of truth shifted the approach away from syntax, to set theory and semantics [Feferman/Feferman on Tarski] |
11195 | If affirmative propositions express being, we affirm about what is absent [Aquinas] |
22103 | Being is basic to thought, and all other concepts are additions to being [Aquinas] |
15812 | Being implies distinctness, which implies division, unity, and multitude [Aquinas] |
21268 | Non-human things are explicable naturally, and voluntary things by the will, so God is not needed [Aquinas] |
16655 | Different genera are delimited by modes of predication, which rest on modes of being [Aquinas] |
16641 | Whiteness does not exist, but by it something can exist-as-white [Aquinas] |
11201 | Properties have an incomplete essence, with definitions referring to their subject [Aquinas] |
11205 | If the form of 'human' contains 'many', Socrates isn't human; if it contains 'one', Socrates is Plato [Aquinas] |
10151 | I am a deeply convinced nominalist [Tarski] |
13090 | The principle of diversity for corporeal substances is their matter [Aquinas, by Cover/O'Leary-Hawthorne] |
17555 | 'One' can mean undivided and not a multitude, or it can add measurement, giving number [Aquinas] |
16765 | Humans only have a single substantial form, which contains the others and acts for them [Aquinas] |
16766 | One thing needs a single thing to unite it; if there were two forms, something must unite them [Aquinas] |
11202 | It is by having essence that things exist [Aquinas] |
11203 | Specific individual essence is defined by material, and generic essence is defined by form [Aquinas] |
11200 | The definition of a physical object must include the material as well as the form [Aquinas] |
11196 | Essence is something in common between the natures which sort things into categories [Aquinas] |
11208 | A simple substance is its own essence [Aquinas] |
22170 | Senses grasp external properties, but the understanding grasps the essential natures of things [Aquinas] |
23175 | The conclusions of speculative reason about necessities are certain [Aquinas] |
21337 | A knowing being possesses a further reality, the 'presence' of the thing known [Aquinas] |
21249 | Some things are self-evident to us; others are only self-evident in themselves [Aquinas] |
22169 | Initial universal truths are present within us as potential, to be drawn out by reason [Aquinas] |
21250 | A proposition is self-evident if the predicate is included in the essence of the subject [Aquinas] |
22168 | Minds take in a likeness of things, which activates an awaiting potential [Aquinas] |
20224 | Sensation prepares the way for intellectual knowledge, which needs the virtues of reason [Aquinas] |
1860 | Knowledge may be based on senses, but we needn't sense all our knowledge [Aquinas] |
22109 | The fullest knowledge places a conclusion within an accurate theory [Aquinas, by Kretzmann/Stump] |
11198 | Definition of essence makes things understandable [Aquinas] |
22107 | Sensations are transmitted to 'internal senses' in the brain, chiefly to 'phantasia' and 'imagination' [Aquinas, by Kretzmann/Stump] |
9098 | Mental activity combines what we sense with imagination of what is not present [Aquinas] |
9092 | Abstracting A from B generates truth, as long as the connection is not denied [Aquinas] |
9093 | We understand the general nature of things by ignoring individual peculiarities [Aquinas] |
9097 | The mind abstracts generalities from images, but also uses images for understanding [Aquinas] |
9095 | Very general ideas (being, oneness, potentiality) can be abstracted from thought matter in general [Aquinas] |
9099 | Particular instances come first, and (pace Plato) generalisations are abstracted from them [Aquinas] |
10508 | Species are abstracted from appearances by ignoring individual conditions [Aquinas] |
22111 | Aquinas attributes freedom to decisions and judgements, and not to the will alone [Aquinas, by Kretzmann/Stump] |
1855 | If we saw something as totally and utterly good, we would be compelled to will it [Aquinas] |
1856 | Nothing can be willed except what is good, but good is very varied, and so choices are unpredictable [Aquinas] |
1862 | However habituated you are, given time to ponder you can go against a habit [Aquinas] |
1849 | Since will is a reasoning power, it can entertain opposites, so it is not compelled to embrace one of them [Aquinas] |
1861 | The will is not compelled to move, even if pleasant things are set before it [Aquinas] |
1853 | Because the will moves by examining alternatives, it doesn't compel itself to will [Aquinas] |
1854 | We must admit that when the will is not willing something, the first movement to will must come from outside the will [Aquinas] |
22105 | The human intellectual soul is an incorporeal, subsistent principle [Aquinas] |
20700 | Without God's influence every operation would stop, so God causes everything [Aquinas] |
22108 | First grasp what it is, then its essential features; judgement is their compounding and division [Aquinas] |
10503 | We abstract forms from appearances, and acquire knowledge of immaterial things [Aquinas] |
10509 | Understanding consists entirely of grasping abstracted species [Aquinas] |
10506 | Mathematics can be abstracted from sensible matter, and from individual intelligible matter [Aquinas] |
9094 | Mathematical objects abstract both from perceived matter, and from particular substance [Aquinas] |
10505 | We can just think of an apple's colour, because the apple is not part of the colour's nature [Aquinas] |
10504 | Abstracting either treats something as separate, or thinks of it separately [Aquinas] |
10507 | Numbers and shapes are abstracted by ignoring their sensible qualities [Aquinas] |
9096 | The mind must produce by its own power an image of the individual species [Aquinas] |
11206 | The mind constructs complete attributions, based on the unified elements of the real world [Aquinas] |
13345 | Sentences are 'analytical' if every sequence of objects models them [Tarski] |
1847 | The will must aim at happiness, but can choose the means [Aquinas] |
1857 | We don't have to will even perfect good, because we can choose not to think of it [Aquinas] |
1846 | The will can only want what it thinks is good [Aquinas] |
23180 | The will is the rational appetite [Aquinas] |
20407 | Taste is the capacity to judge an object or representation which is thought to be beautiful [Tarski, by Schellekens] |
1850 | Without free will not only is ethical action meaningless, but also planning, commanding, praising and blaming [Aquinas] |
22112 | For humans good is accordance with reason, and bad is contrary to reason [Aquinas] |
22494 | We must know the end, know that it is the end, and know how to attain it [Aquinas] |
1851 | Good applies to goals, just as truth applies to ideas in the mind [Aquinas] |
3031 | The greatest good is not the achievement of desire, but to desire what is proper [Menedemus, by Diog. Laertius] |
23181 | All acts of virtue relate to justice, which is directed towards the common good [Aquinas] |
8009 | Aquinas wanted, not to escape desire, but to transform it for moral ends [Aquinas, by MacIntyre] |
23182 | Legal justice is supreme, because it directs the other virtues to the common good [Aquinas] |
22399 | Temperance prevents our passions from acting against reason [Aquinas] |
23177 | Justice directs our relations with others, because it denotes a kind of equality [Aquinas] |
23179 | People differ in their social degrees, and a particular type of right applies to each [Aquinas] |
23174 | Natural law is a rational creature's participation in eternal law [Aquinas] |
22113 | Right and wrong actions pertain to natural law, as perceived by practical reason [Aquinas] |
22114 | Tyrannical laws are irrational, and so not really laws [Aquinas] |
7291 | For Aquinas a war must be in a just cause, have proper authority, and aim at good [Aquinas, by Grayling] |
5508 | Aquinas says a fertilized egg is not human, and has no immortal soul [Aquinas, by Martin/Barresi] |
16687 | Bodies are three-dimensional substances [Aquinas] |
11207 | A cause can exist without its effect, but the effect cannot exist without its cause [Aquinas] |
1859 | Even a sufficient cause doesn't compel its effect, because interference could interrupt the process [Aquinas] |
15202 | Eternity coexists with passing time, as the centre of a circle coexists with its circumference [Aquinas] |
23178 | Divine law commands some things because they are good, while others are good because commanded [Aquinas] |
21251 | We can't know God's essence, so his existence can't be self-evident for us [Aquinas] |
5614 | If you assume that there must be a necessary being, you can't say which being has this quality [Kant on Aquinas] |
21269 | Way 1: the infinite chain of potential-to-actual movement has to have a first mover [Aquinas] |
21270 | Way 2: no effect without a cause, and this cannot go back to infinity, so there is First Cause [Aquinas] |
21271 | Way 3: contingent beings eventually vanish, so continuity needs a necessary being [Aquinas] |
21272 | Way 4: the source of all qualities is their maximum, so something (God) causes all perfections [Aquinas] |
21273 | Way 5: mindless things act towards an obvious end, so there is an intelligent director [Aquinas] |
20211 | Life aims at the Beatific Vision - of perfect happiness, and revealed truth [Aquinas, by Zagzebski] |
22106 | Aquinas saw angels as separated forms, rather than as made of 'spiritual matter' [Aquinas, by Kretzmann/Stump] |
16711 | Heretics should be eradicated like wolves [Aquinas] |
23306 | Humans have a non-physical faculty of reason, so they can be immortal [Aquinas, by Sorabji] |
1863 | If the soul achieves well-being in another life, it doesn't follow that I do [Aquinas] |
4412 | Those in bliss have their happiness increased by seeing the damned punished [Aquinas] |
21266 | God does not exist, because He is infinite and good, and so no evil should be discoverable [Aquinas] |
21274 | It is part of God's supreme goodness that He brings good even out of evil [Aquinas] |