70 ideas
1798 | He studied philosophy by suspending his judgement on everything [Pyrrho, by Diog. Laertius] |
Full Idea: He studied philosophy on the principle of suspending his judgement on all points. | |
From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.3 | |
A reaction: In what sense was Pyrrho a philosopher, then? He must have asserted SOME generalised judgments. |
15357 | Philosophy is the most general intellectual discipline [Horsten] |
Full Idea: Philosophy is the most general intellectual discipline. | |
From: Leon Horsten (The Tarskian Turn [2011], 05.1) | |
A reaction: Very simple, but exactly how I see the subject. It is continuous with the sciences, and tries to give an account of nature, but operating at an extreme level of generality. It must respect the findings of science, but offer bold interpretations. |
1800 | Sceptics say reason is only an instrument, because reason can only be attacked with reason [Pyrrho, by Diog. Laertius] |
Full Idea: The Sceptics say that they only employ reason as an instrument, because it is impossible to overturn the authority of reason, without employing reason. | |
From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.8 |
15352 | A definition should allow the defined term to be eliminated [Horsten] |
Full Idea: A definition allows a defined term to be eliminated in every context in which it appears. | |
From: Leon Horsten (The Tarskian Turn [2011], 04.2) | |
A reaction: To do that, a definition had better be incredibly comprehensive, so that no nice nuance of the original term is thrown out. |
15323 | Truth is a property, because the truth predicate has an extension [Horsten] |
Full Idea: I take truth to be a property because the truth predicate has an extension - the collection of all true sentences - and this collection does not (unlike the 'extension' of 'exists') consist of everything, or even of all sentences. | |
From: Leon Horsten (The Tarskian Turn [2011], 01.1) | |
A reaction: He concedes that it may be an 'uninteresting' property. My problem is always that I am unconvinced that truth is tied to sentences. I can make perfect sense of animal thoughts being right or wrong. Extension of mental propositions? |
15324 | Semantic theories of truth seek models; axiomatic (syntactic) theories seek logical principles [Horsten] |
Full Idea: There are semantical theories of truth, concerned with models for languages containing the truth predicate, and axiomatic (or syntactic) theories, interested in basic logical principles governing the concept of truth. | |
From: Leon Horsten (The Tarskian Turn [2011], 01.1) | |
A reaction: This is the map of contemporary debates, which seem now to have given up talking about 'correspondence', 'coherence' etc. |
15374 | Truth has no 'nature', but we should try to describe its behaviour in inferences [Horsten] |
Full Idea: We should not aim at describing the nature of truth because there is no such thing. Rather, we should aim at describing the inferential behaviour of truth. | |
From: Leon Horsten (The Tarskian Turn [2011], 10.2.3) |
22462 | We should speak the truth, but also preserve and pursue it [Foot] |
Full Idea: There belongs to truthfulness not only the avoidance of lying but also that other kind of attachment to truth which has to do with its preservation and pursuit. | |
From: Philippa Foot (Utilitarianism and the Virtues [1985], p.74) | |
A reaction: This is truth as a value, rather than as a mere phenomenon of accurate thought and speech. The importance of 'preserving' the truth is the less common part of this idea. |
15348 | Propositions have sentence-like structures, so it matters little which bears the truth [Horsten] |
Full Idea: It makes little difference, at least in extensional contexts, whether the truth bearers are propositions or sentences (or assertions). Even if the bearers are propositions rather than sentences, propositions are structured rather like sentences. | |
From: Leon Horsten (The Tarskian Turn [2011], 02.4) | |
A reaction: The 'extensional' context means you are only talking about the things that are referred to, and not about the way this is expressed. I prefer propositions, but this is an interesting point. |
15333 | Modern correspondence is said to be with the facts, not with true propositions [Horsten] |
Full Idea: Modern correspondence theorists no longer take things to correspond to true propositions; they consider facts to be the truthmakers of propositions. | |
From: Leon Horsten (The Tarskian Turn [2011], 02.1) | |
A reaction: If we then define facts as the way certain things are, independently from our thinking about it, at least we seem to be avoiding circularity. Not much point in correspondence accounts if you are not a robust realist (like me). [14,000th idea, 23/4/12!] |
15337 | The correspondence 'theory' is too vague - about both 'correspondence' and 'facts' [Horsten] |
Full Idea: The principle difficulty of the correspondence theory of truth is its vagueness. It is too vague to be called a theory until more information is given about what is meant by the terms 'correspondence' and 'fact'. Facts can involve a heavy ontology. | |
From: Leon Horsten (The Tarskian Turn [2011], 02.1) | |
A reaction: I see nothing here to make me give up my commitment to the correspondence view of truth, though it sounds as if I will have to give up the word 'theory' in that context. Truth is so obviously about thought fitting reality that there is nothing to discuss. |
15334 | The coherence theory allows multiple coherent wholes, which could contradict one another [Horsten] |
Full Idea: The coherence theory seems too liberal. It seems there can be more than one systematic whole which, while being internally coherent, contradict each other, and thus cannot all be true. Coherence is a necessary but not sufficient condition for truth. | |
From: Leon Horsten (The Tarskian Turn [2011], 02.1) | |
A reaction: This is a modern post-Tarski axiomatic truth theorist making very short work indeed of the coherence theory of truth. I take Horsten to be correct. |
15336 | The pragmatic theory of truth is relative; useful for group A can be useless for group B [Horsten] |
Full Idea: The pragmatic theory is unsatisfactory because usefulness is a relative notion. One theory can be useful to group A while being thoroughly impractical for group B. This would make the theory both truth and false. | |
From: Leon Horsten (The Tarskian Turn [2011], 02.1) | |
A reaction: This objection, along with the obvious fact that certain falsehoods can be very useful, would seem to rule pragmatism out as a theory of truth. It is, in fact, an abandonment of truth. |
15354 | Tarski's hierarchy lacks uniform truth, and depends on contingent factors [Horsten] |
Full Idea: According to the Tarskian hierarchical conception, truth is not a uniform notion. ...Also Kripke has emphasised that the level of a token of the truth predicate can depend on contingent factors, such as what else has been said by a speaker. | |
From: Leon Horsten (The Tarskian Turn [2011], 04.5) |
15340 | Tarski Bi-conditional: if you'll assert φ you'll assert φ-is-true - and also vice versa [Horsten] |
Full Idea: The axiom schema 'Sentence "phi;" is true iff φ' is the (unrestricted) Tarski-Biconditional, and is motivated by the thought that if you are willing to assume or outright assert that φ, you will assert that φ is true - and also vice versa. | |
From: Leon Horsten (The Tarskian Turn [2011], 02.2) | |
A reaction: Very helpful! Most people are just bewildered by the Tarski bi-conditional ('"Snow is white"...), but this formulation nicely shows its minimal character while showing that it really does say something. It says what truths and truth-claims commit you to. |
15345 | Semantic theories have a regress problem in describing truth in the languages for the models [Horsten] |
Full Idea: Semantic theories give a class of models with a truth predicate, ...but Tarski taught us that this needs a more encompassing framework than its language...so how is the semantics of the framework expressed? The model route has a regress. | |
From: Leon Horsten (The Tarskian Turn [2011], 02.3) | |
A reaction: [compressed] So this regress problem, of endless theories of truth going up the hierarchy, is Horsten's main reason for opting for axiomatic theories, which he then tries to strengthen, so that they are not quite so deflated. |
15332 | 'Reflexive' truth theories allow iterations (it is T that it is T that p) [Horsten] |
Full Idea: A theory of truth is 'reflexive' if it allows us to prove truth-iterations ("It is true that it is true that so-and-so"). | |
From: Leon Horsten (The Tarskian Turn [2011], 01.4) |
15346 | Axiomatic approaches to truth avoid the regress problem of semantic theories [Horsten] |
Full Idea: The axiomatic approach to truth does not suffer from the regress problem. | |
From: Leon Horsten (The Tarskian Turn [2011], 02.3) | |
A reaction: See Idea 15345 for the regress problem. The difficulty then seems to be that axiomatic approaches lack expressive power, so the hunt is on for a set of axioms which will do a decent job. Fun work, if you can cope with it. |
15361 | A good theory of truth must be compositional (as well as deriving biconditionals) [Horsten] |
Full Idea: Deriving many Tarski-biconditionals is not a sufficient condition for being a good theory of truth. A good theory of truth must in addition do justice to the compositional nature of truth. | |
From: Leon Horsten (The Tarskian Turn [2011], 06.1) |
15371 | An axiomatic theory needs to be of maximal strength, while being natural and sound [Horsten] |
Full Idea: The challenge is to find the arithmetically strongest axiomatical truth theory that is both natural and truth-theoretically sound. | |
From: Leon Horsten (The Tarskian Turn [2011], 07.7) |
15350 | The Naďve Theory takes the bi-conditionals as axioms, but it is inconsistent, and allows the Liar [Horsten] |
Full Idea: The Naďve Theory of Truth collects all the Tarski bi-conditionals of a language and takes them as axioms. But no consistent theory extending Peano arithmetic can prove all of them. It is inconsistent, and even formalises the liar paradox. | |
From: Leon Horsten (The Tarskian Turn [2011], 03.5.2) | |
A reaction: [compressed] This looks to me like the account of truth that Davidson was working with, since he just seemed to be compiling bi-conditionals for tricky cases. (Wrong! He championed the Compositional Theory, Horsten p.71) |
15351 | Axiomatic theories take truth as primitive, and propose some laws of truth as axioms [Horsten] |
Full Idea: In the axiomatic approach we take the truth predicate to express an irreducible, primitive notion. The meaning of the truth predicate is partially explicated by proposing certain laws of truth as basic principles, as axioms. | |
From: Leon Horsten (The Tarskian Turn [2011], 04.2) | |
A reaction: Judging by Horsten's book, this is a rather fruitful line of enquiry, but it still seems like a bit of a defeat to take truth as 'primitive'. Presumably you could add some vague notion of correspondence as the background picture. |
15367 | By adding truth to Peano Arithmetic we increase its power, so truth has mathematical content! [Horsten] |
Full Idea: It is surprising that just by adding to Peano Arithmetic principles concerning the notion of truth, we increase the mathematical strength of PA. So, contrary to expectations, the 'philosophical' notion of truth has real mathematical content. | |
From: Leon Horsten (The Tarskian Turn [2011], 06.4) | |
A reaction: Horsten invites us to be really boggled by this. All of this is in the Compositional Theory TC. It enables a proof of the consistency of arithmetic (but still won't escape Gödel's Second). |
15373 | Axiomatic approaches avoid limiting definitions to avoid the truth predicate, and limited sizes of models [Horsten] |
Full Idea: An adequate definition of truth can only be given for the fragment of our language that does not contain the truth predicate. A model can never encompass the whole of the domain of discourse of our language. The axiomatic approach avoids these problems. | |
From: Leon Horsten (The Tarskian Turn [2011], 10.1) |
15330 | Friedman-Sheard theory keeps classical logic and aims for maximum strength [Horsten] |
Full Idea: The Friedman-Sheard theory of truth holds onto classical logic and tries to construct a theory that is as strong as possible. | |
From: Leon Horsten (The Tarskian Turn [2011], 01.4) |
15331 | Kripke-Feferman has truth gaps, instead of classical logic, and aims for maximum strength [Horsten] |
Full Idea: If we abandon classical logic in favour of truth-value gaps and try to strengthen the theory, this leads to the Kripke-Feferman theory of truth, and variants of it. | |
From: Leon Horsten (The Tarskian Turn [2011], 01.4) |
15325 | Inferential deflationism says truth has no essence because no unrestricted logic governs the concept [Horsten] |
Full Idea: According to 'inferential deflationism', truth is a concept without a nature or an essence. This is betrayed by the fact that there are no unrestricted logical laws that govern the concept of truth. | |
From: Leon Horsten (The Tarskian Turn [2011], 01.1) |
15356 | Deflationism concerns the nature and role of truth, but not its laws [Horsten] |
Full Idea: Deflationism is not a theory of the laws of truth. It is a view on the nature and role of the concept of truth. | |
From: Leon Horsten (The Tarskian Turn [2011], 05 Intro) |
15344 | Deflationism skips definitions and models, and offers just accounts of basic laws of truth [Horsten] |
Full Idea: Contemporary deflationism about truth does not attempt to define truth, and does not rely on models containing the truth predicate. Instead they are interpretations of axiomatic theories of truth, containing only basic laws of truth. | |
From: Leon Horsten (The Tarskian Turn [2011], 02.3) |
15368 | This deflationary account says truth has a role in generality, and in inference [Horsten] |
Full Idea: On the conception of deflationism developed in this book, the prime positive role of the truth predicate is to serve as a device for expressing generalities, and an inferential tool. | |
From: Leon Horsten (The Tarskian Turn [2011], 07.5) |
15358 | Deflationism says truth isn't a topic on its own - it just concerns what is true [Horsten] |
Full Idea: Deflationism says the theory of truth does not have a substantial domain of its own. The domain of the theory of truth consists of the bearers of truth. | |
From: Leon Horsten (The Tarskian Turn [2011], 05.1) | |
A reaction: The immediate thought is that truth also concerns falsehoods, which would be inexplicable without it. If physics just concerns the physical, does that mean that physics lacks its own 'domain'? Generalising about the truths is a topic. |
15359 | Deflation: instead of asserting a sentence, we can treat it as an object with the truth-property [Horsten] |
Full Idea: The Deflationary view just says that instead of asserting a sentence, we can turn the sentence into an object and assert that this object has the property of truth. | |
From: Leon Horsten (The Tarskian Turn [2011], 05.2.2) | |
A reaction: That seems to leave a big question hanging, which concerns the nature of the property that is being attributed to this object. Quine 1970:10-13 says it is just a 'device'. Surely you can rest content with that as an account of truth? |
15329 | Nonclassical may accept T/F but deny applicability, or it may deny just T or F as well [Horsten] |
Full Idea: Some nonclassical logic stays close to classical, assuming two mutually exclusive truth values T and F, but some sentences fail to have one. Others have further truth values such as 'half truth', or dialethists allow some T and F at the same time. | |
From: Leon Horsten (The Tarskian Turn [2011], 01.2) | |
A reaction: I take that to say that the first lot accept bivalence but reject excluded middle (allowing 'truth value gaps'), while the second lot reject both. Bivalence gives the values available, and excluded middle says what has them. |
15326 | Doubt is thrown on classical logic by the way it so easily produces the liar paradox [Horsten] |
Full Idea: Aside from logic, so little is needed to generate the liar paradox that one wonders whether the laws of classical logic are unrestrictedly valid after all. (Many theories of truth have therefore been formulated in nonclassical logic.) | |
From: Leon Horsten (The Tarskian Turn [2011], 01.2) | |
A reaction: Kripke uses Strong Kleene logic for his theory. The implication is that debates discussed by Horsten actually have the status of classical logic at stake, as well as the nature of truth. |
15341 | Deduction Theorem: ψ only derivable from φ iff φ→ψ are axioms [Horsten] |
Full Idea: The Deduction Theorem says ψ is derivable in classical predicate logic from ψ iff the sentence φ→ψ is a theorem of classical logic. Hence inferring φ to ψ is truth-preserving iff the axiom scheme φ→ψ is provable. | |
From: Leon Horsten (The Tarskian Turn [2011], 02.2) | |
A reaction: Horsten offers this to show that the Tarski bi-conditionals can themselves be justified, and not just the rule of inference involved. Apparently you can only derive something if you first announce that you have the ability to derive it. Odd. |
15328 | A theory is 'non-conservative' if it facilitates new mathematical proofs [Horsten] |
Full Idea: A theory is 'non-conservative' if it allows us to prove mathematical facts that go beyond what the background mathematical theory can prove on its own. | |
From: Leon Horsten (The Tarskian Turn [2011], 01.4) | |
A reaction: This is an instance of the relationship with mathematics being used as the test case for explorations of logic. It is a standard research method, because it is so precise, but should not be mistaken for the last word about a theory. |
15349 | It is easier to imagine truth-value gaps (for the Liar, say) than for truth-value gluts (both T and F) [Horsten] |
Full Idea: It is easier to imagine what it is like for a sentence to lack a truth value than what it is like for a sentence to be both truth and false. So I am grudgingly willing to entertain the possibility that certain sentences (like the Liar) lack a truth value. | |
From: Leon Horsten (The Tarskian Turn [2011], 02.5) | |
A reaction: Fans of truth value gluts are dialethists like Graham Priest. I'm with Horsten on this one. But in what way can a sentence be meaningful if it lacks a truth-value? He mentions unfulfilled presuppositions and indicative conditionals as gappy. |
15366 | Satisfaction is a primitive notion, and very liable to semantical paradoxes [Horsten] |
Full Idea: Satisfaction is a more primitive notion than truth, and it is even more susceptible to semantical paradoxes than the truth predicate. | |
From: Leon Horsten (The Tarskian Turn [2011], 06.3) | |
A reaction: The Liar is the best known paradox here. Tarski bases his account of truth on this primitive notion, so Horsten is pointing out the difficulties. |
15353 | The first incompleteness theorem means that consistency does not entail soundness [Horsten] |
Full Idea: It is a lesson of the first incompleteness theorem that consistency does not entail soundness. If we add the negation of the gödel sentence for PA as an extra axiom to PA, the result is consistent. This negation is false, so the theory is unsound. | |
From: Leon Horsten (The Tarskian Turn [2011], 04.3) |
15355 | Strengthened Liar: 'this sentence is not true in any context' - in no context can this be evaluated [Horsten] |
Full Idea: The Strengthened Liar sentence says 'this sentence is not true in any context'. It is not hard to figure out that there is no context in which the sentence can be coherently evaluated. | |
From: Leon Horsten (The Tarskian Turn [2011], 04.6) |
15364 | English expressions are denumerably infinite, but reals are nondenumerable, so many are unnameable [Horsten] |
Full Idea: The number of English expressions is denumerably infinite. But Cantor's theorem can be used to show that there are nondenumerably many real numbers. So not every real number has a (simple or complex name in English). | |
From: Leon Horsten (The Tarskian Turn [2011], 06.3) | |
A reaction: This really bothers me. Are we supposed to be committed to the existence of entities which are beyond our powers of naming? How precise must naming be? If I say 'pick a random real number', might that potentially name all of them? |
15360 | ZFC showed that the concept of set is mathematical, not logical, because of its existence claims [Horsten] |
Full Idea: One of the strengths of ZFC is that it shows that the concept of set is a mathematical concept. Many originally took it to be a logical concept. But ZFC makes mind-boggling existence claims, which should not follow if it was a logical concept. | |
From: Leon Horsten (The Tarskian Turn [2011], 05.2.3) | |
A reaction: This suggests that set theory is not just a way of expressing mathematics (see Benacerraf 1965), but that some aspect of mathematics has been revealed by it - maybe even its essential nature. |
15369 | Set theory is substantial over first-order arithmetic, because it enables new proofs [Horsten] |
Full Idea: The nonconservativeness of set theory over first-order arithmetic has done much to establish set theory as a substantial theory indeed. | |
From: Leon Horsten (The Tarskian Turn [2011], 07.5) | |
A reaction: Horsten goes on to point out the price paid, which is the whole new ontology which has to be added to the arithmetic. Who cares? It's all fictions anyway! |
15370 | Predicativism says mathematical definitions must not include the thing being defined [Horsten] |
Full Idea: Predicativism has it that a mathematical object (such as a set of numbers) cannot be defined by quantifying over a collection that includes that same mathematical object. To do so would be a violation of the vicious circle principle. | |
From: Leon Horsten (The Tarskian Turn [2011], 07.7) | |
A reaction: In other words, when you define an object you are obliged to predicate something new, and not just recycle the stuff you already have. |
15338 | We may believe in atomic facts, but surely not complex disjunctive ones? [Horsten] |
Full Idea: While positive and perhaps even negative atomic facts may be unproblematic, it seems excessive to commit oneself to the existence of logically complex facts such as disjunctive facts. | |
From: Leon Horsten (The Tarskian Turn [2011], 02.1) | |
A reaction: Presumably it is hard to deny that very complex statements involving massive disjunctions can be true or false. But why does commitment to real facts have to involve a huge ontology? The ontology is just the ingredients of the fact, isn't it? |
15363 | In the supervaluationist account, disjunctions are not determined by their disjuncts [Horsten] |
Full Idea: If 'Britain is large' and 'Italy is large' lack truth values, then so must 'Britain or Italy is large' - so on the supervaluationist account the truth value of a disjunction is not determined by the truth values of its disjuncts. | |
From: Leon Horsten (The Tarskian Turn [2011], 06.2) | |
A reaction: Compare Idea 15362 to get the full picture here. |
15362 | If 'Italy is large' lacks truth, so must 'Italy is not large'; but classical logic says it's large or it isn't [Horsten] |
Full Idea: If 'Italy is a large country' lacks a truth value, then so too, presumably, does 'Italy is not a large country'. But 'Italy is or is not a large country' is true, on the supervaluationist account, because it is a truth of classical propositional logic. | |
From: Leon Horsten (The Tarskian Turn [2011], 06.2) | |
A reaction: See also Idea 15363. He cites Fine 1975. |
15372 | Some claim that indicative conditionals are believed by people, even though they are not actually held true [Horsten] |
Full Idea: In the debate about doxastic attitudes towards indicative conditional sentences, one finds philosophers who claim that conditionals can be believed even though they have no truth value (and thus are not true). | |
From: Leon Horsten (The Tarskian Turn [2011], 09.3) |
6595 | If we need a criterion of truth, we need to know whether it is the correct criterion [Pyrrho, by Fogelin] |
Full Idea: Against the Stoics, the Pyrrhonians argued that if someone presents a criterion of truth, then it will be important to determine whether it is the correct criterion. | |
From: report of Pyrrho (reports [c.325 BCE]) by Robert Fogelin - Walking the Tightrope of Reason Ch.4 | |
A reaction: Hence Davidson says that attempts to define truth are 'folly'. If something has to be taken as basic, then truth seems a good candidate (since, for example, logical operators could not otherwise be defined by means of 'truth' tables). |
6593 | The Pyrrhonians attacked the dogmas of professors, not ordinary people [Pyrrho, by Fogelin] |
Full Idea: The attacks of the Pyrrhonian sceptics are directed against the dogmas of the 'professors', not against the beliefs of the common people pursuing the business of daily life. | |
From: report of Pyrrho (reports [c.325 BCE]) by Robert Fogelin - Walking the Tightrope of Reason Ch.4 | |
A reaction: This may be because they thought that ordinary people were too confused to be worth attacking, rather than because they lived in a state of beautifully appropriate beliefs. Naďve realism is certainly worth attacking. |
6592 | Academics said that Pyrrhonians were guilty of 'negative dogmatism' [Pyrrho, by Fogelin] |
Full Idea: The ancient Academic sceptics charged the Pyrrhonian sceptics with 'negative dogmatism' when they claimed that a certain kind of knowledge is impossible. | |
From: report of Pyrrho (reports [c.325 BCE]) by Robert Fogelin - Walking the Tightrope of Reason Ch.4 | |
A reaction: It is this kind of point which should push us towards some sort of rationalism, because certain a priori 'dogmas' seem to be indispensable to get any sort of discussion off the ground. The only safe person is Cratylus (see Idea 578). |
1801 | Animals vary in their feelings and judgements (Mode 1) [Pyrrho, by Diog. Laertius] |
Full Idea: First mode: animals vary in their feelings and judgements (of food, for example). | |
From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
1803 | Objects vary according to which sense perceives them (Mode 3) [Pyrrho, by Diog. Laertius] |
Full Idea: Third mode: things like an apple vary according to which sense perceives them (yellow, sweet, and fragrant). | |
From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
1809 | Perception is affected by expectations (Mode 9) [Pyrrho, by Diog. Laertius] |
Full Idea: Ninth mode: we perceive things according to what we expect (earthquakes and sunshine). | |
From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
1805 | Judgements vary according to local culture and law (Mode 5) [Pyrrho, by Diog. Laertius] |
Full Idea: Fifth mode: judgements vary according to local custom, law and culture (Persians marry their daughters). | |
From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
1808 | Perception of things depends on their size or quantity (Mode 8) [Pyrrho, by Diog. Laertius] |
Full Idea: Eighth mode: perceptions of things depend on their magnitude or quantity (food and wine). | |
From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
1804 | Perception varies with madness or disease (Mode 4) [Pyrrho, by Diog. Laertius] |
Full Idea: Fourth mode: perceivers vary in their mental and physical state (such as the mad and the sick). | |
From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
1806 | Perception of objects depends on surrounding conditions (Mode 6) [Pyrrho, by Diog. Laertius] |
Full Idea: Sixth mode: the perception of an object depends on surrounding conditions (sunlight and lamplight). | |
From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
1802 | Individuals vary in responses and feelings (Mode 2) [Pyrrho, by Diog. Laertius] |
Full Idea: Second mode: individual men vary in responses and feelings (heat and cold, for example). | |
From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
1807 | Perception varies with viewing distance and angle (Mode 7) [Pyrrho, by Diog. Laertius] |
Full Idea: Seventh mode: perception varies according to viewing distance and angle (the sun, and a dove's neck). | |
From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
1810 | Perception and judgement depend on comparison (Mode 10) [Pyrrho, by Diog. Laertius] |
Full Idea: Tenth mode: perceptions and judgements depend on comparison (light/heavy, above/below). | |
From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9 |
15347 | A theory of syntax can be based on Peano arithmetic, thanks to the translation by Gödel coding [Horsten] |
Full Idea: A notion of formal provability can be articulated in Peano arithmetic. ..This is surprisingly 'linguistic' rather than mathematical, but the key is in the Gödel coding. ..Hence we use Peano arithmetic as a theory of syntax. | |
From: Leon Horsten (The Tarskian Turn [2011], 02.4) | |
A reaction: This is the explanation of why issues in formal semantics end up being studied in systems based on formal arithmetic. And I had thought it was just because they were geeks who dream in numbers, and can't speak language properly... |
22458 | Consequentialists can hurt the innocent in order to prevent further wickedness [Foot] |
Full Idea: For consequentialists there will be nothing that it will not be right to do to a perfectly innocent individual, if that is the only way of preventing another agent from doing more things of the same kind. | |
From: Philippa Foot (Utilitarianism and the Virtues [1985], p.61) | |
A reaction: This is her generalised version that Williams dramatised as Jim and the Indians. Roughly, if you achieve a good outcome, it matters little how it is achieved. Foot sees consequentialism as the main problem with utilitarianism. |
22460 | Why might we think that a state of affairs can be morally good or bad? [Foot] |
Full Idea: We should ask why we think that it makes sense to talk about morally good and bad states of affairs. | |
From: Philippa Foot (Utilitarianism and the Virtues [1985], p.68) | |
A reaction: This is the key question in her attack on consequentialism. There is nothing 'morally' good about my football team winning a great victory. |
22461 | Good outcomes are not external guides to morality, but a part of virtuous actions [Foot] |
Full Idea: It is not that maximum welfare or 'the best outcome' stands outside morality as it foundation and arbiter, but rather that it appears within morality as the end of one of the virtues. | |
From: Philippa Foot (Utilitarianism and the Virtues [1985], p.73) | |
A reaction: She cites justice and benevolence as aiming at different (and even conflicting) outcomes. I'm not sure about her distinction between 'outside' and 'within' morality. I suppose a virtuously created end is a moral end, unlike mere good states of affairs. |
22464 | The idea of a good state of affairs has no role in the thought of Aristotle, Rawls or Scanlon [Foot] |
Full Idea: The idea of the goodness of total states of affairs played no part in Aristotle's moral philosophy, and in modern times plays not part either in Rawls's account of justice or in the theories of more thoroughgoing contractualists such as Scanlon. | |
From: Philippa Foot (Utilitarianism and the Virtues [1985], p.76) | |
A reaction: We can add Kant to that. But if the supremely good state of affairs were permanently achieved, would that make morality irrelevant? A community of the exceptionally virtuous would not need the veil of ignorance, or contracts. |
22463 | Morality is seen as tacit legislation by the community [Foot] |
Full Idea: Morality is thought of as a kind of tacit legislation by the community. | |
From: Philippa Foot (Utilitarianism and the Virtues [1985], p.75) | |
A reaction: Foot presents this as a utilitarian doctrine, because the tacit legislation is felt to produce the best outcomes. This is Nietzsche's good and evil, beyond which he wished to go (presumably following other values). |
22459 | For consequentialism, it is irrational to follow a rule which in this instance ends badly [Foot] |
Full Idea: It would be irrational to obey even the most useful rule if in a particular instance we clearly see that such obedience will not have the best results. | |
From: Philippa Foot (Utilitarianism and the Virtues [1985], p.62) | |
A reaction: This is the simple reason why attempts at rule utilitarianism always lead back to act utilitarianism. Another way of putting it is that a good rule can only be assessed by the outcomes of individual acts that follow it. |
3062 | There are no causes, because they are relative, and alike things can't cause one another [Pyrrho, by Diog. Laertius] |
Full Idea: The idea of cause is relative to that of which it is the cause, and so has no real existence. …Also cause must either be body causing body, or incorporeal causing incorporeal, and neither of these is possible. | |
From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.11.11 |
3063 | Motion can't move where it is, and can't move where it isn't, so it can't exist [Pyrrho, by Diog. Laertius] |
Full Idea: Motion is not moved in the place in which it is is, and it is impossible that it should be moved in the place in which it is not, so there is no such thing as motion. | |
From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.11.11 |