97 ideas
| 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. |
| 21900 | Deleuze relies on Spinoza (immanence), Bergson (duration), and difference (Nietzsche) [May] |
| Full Idea: The three tripods on which the philosophy of Deleuze stands are immanence (Spinoza), duration (Bergson), and the affirmation of difference (Nietzsche). | |
| From: Todd May (Gilles Deleuze [2006], 2.12) | |
| A reaction: [Just to begin sketching how continental philosophy sees its tradition]. |
| 7614 | Bracketing subtracts entailments about external reality from beliefs [Husserl, by Putnam] |
| Full Idea: In effect, the device of bracketing subtracts entailments from the ordinary belief locution (the entailments that refer to what is external to the thinker's mind). | |
| From: report of Edmund Husserl (Logical Investigations [1900]) by Hilary Putnam - Reason, Truth and History Ch.2 | |
| A reaction: This seems to leave phenomenology as pure introspection, or as a phenomenalist description of sense-data. It is also a refusal to explain anything. That sounds quite appealing, like Keats's 'negative capability'. |
| 6893 | Phenomenology aims to describe experience directly, rather than by its origins or causes [Husserl, by Mautner] |
| Full Idea: Phenomenology, in Husserl, is an attempt to describe our experience directly, as it is, separately from its origins and development, independently of the causal explanations that historians, sociologists or psychologists might give. | |
| From: report of Edmund Husserl (Logical Investigations [1900]) by Thomas Mautner - Penguin Dictionary of Philosophy p.421 | |
| A reaction: In this simple definition the concept sounds very like the modern popular use of the word 'deconstruction', though that is applied more commonly to cultural artifacts than to actual sense experience. |
| 22216 | Phenomenology studies different types of correlation between consciousness and its objects [Husserl, by Bernet] |
| Full Idea: Husserl's phenomenology is the science of the intentional correlation of acts of consciousness with their objects and it studies the ways in which different kinds of objects involve different kinds of correlation with different kinds of acts. | |
| From: report of Edmund Husserl (Ideas: intro to pure phenomenology [1913]) by Rudolf Bernet - Husserl p.198 | |
| A reaction: I notice he uncritically accepts Husserl's description of it as a 'science'. My naive question is how you would distinguish one kind of 'correlation' from another. |
| 21217 | Phenomenology needs absolute reflection, without presuppositions [Husserl] |
| Full Idea: Phenomenology demands the most perfect freedom from presuppositions and, concerning itself, an absolute reflective insight. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], III.1.063), quoted by Victor Velarde-Mayol - On Husserl 3.1 | |
| A reaction: As an outsider, I would have thought that the whole weight of modern continental philosophy is entirely opposed to the aspiration to think without presuppositions. |
| 22218 | There can only be a science of fluctuating consciousness if it focuses on stable essences [Husserl, by Bernet] |
| Full Idea: How can there be a science of a Heraclitean flux of acts of consciousness? Husserl answers that this is possible only if these acts are described in respect of their invariant or essential structure. This is an 'eidetic' scence of 'pure' psychology. | |
| From: report of Edmund Husserl (Ideas: intro to pure phenomenology [1913]) by Rudolf Bernet - Husserl p.199 | |
| A reaction: This is his phenomenology in 1913, which Bernet describes as 'static'. Husserl later introduced time with his 'genetic' version of phenomenology, looking at the sources of experience (and then at history). Essentialism seems to be intuitive. |
| 22217 | Phenomenology aims to validate objects, on the basis of intentional intuitive experience [Husserl, by Bernet] |
| Full Idea: Husserl's goal is to account for the validity, the 'being-true', of objects on the basis of the way in which they are given or constituted. ...Experiences more suitable for guaranteeing objects are those which both intend and intuitively apprehend them. | |
| From: report of Edmund Husserl (Ideas: intro to pure phenomenology [1913]) by Rudolf Bernet - Husserl p.199 | |
| A reaction: [compressed] In the light of previous scepticism and idealism, the project sounds a bit optimistic. If there is a gulf between mind and world it can only be bridged by 'reaching out' from both sides. This is a mind-sided attempt. |
| 22219 | Husserl saw transcendental phenomenology as idealist, in its construction of objects [Husserl, by Bernet] |
| Full Idea: Phenomeonology is 'transcendental' in describing the correlation between phenomena and intentional objects, to show how their meaning and validity are constructed. Husserl gave this process an idealist interpretation (which Heidegger criticised). | |
| From: report of Edmund Husserl (Ideas: intro to pure phenomenology [1913]) by Rudolf Bernet - Husserl p.200 | |
| A reaction: [compressed] If the actions which produce our concepts of objects all take place 'behind' phenomenal consciousness, then it is hard to avoid sliding into some sort of idealism. It encourages direct realism about perception. |
| 22204 | Start philosophising with no preconceptions, from the intuitively non-theoretical self-given [Husserl] |
| Full Idea: Where other philosophers ...start from unclarified, ungrounded preconceptions, we start out from that which antedates all standpoints: from the totality of the intuitively self-given which is prior to any theorising reflexion. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], I.2.020) | |
| A reaction: This is the great aim of Phenomenology, which is obviously inspired by Hegel's similar desire to start from nothing. Hegel starts from a concept ('nothing'), but Husserl starts from raw experience. I suspect both approaches are idle dreams. |
| 22207 | Epoché or 'bracketing' is refraining from judgement, even when some truths are certain [Husserl] |
| Full Idea: In relation to every thesis we can use this peculiar epoché (the phenomenon of 'bracketing' or 'disconnecting'), a certain refraining from judgment which is compatible with the unshaken and unshakable because self-evidencing conviction of Truth. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], II.1.031) | |
| A reaction: This is the crucial first step of Phenomenology. It seems to me that it is best described as 'methodological scepticism'. People actually practise it all the time, while they focus on some experience, while trying to forget preconceptions. |
| 22208 | 'Bracketing' means no judgements at all about spatio-temporal existence [Husserl] |
| Full Idea: I use the 'phenomenological' epoché, which completely bars me from using any judgment that concerns spatio-temporal existence. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], II.1.032) | |
| A reaction: This makes bracketing (or epoché) into a sort of voluntary idealism. Put like that, it is hard to see what benefits it could bring. I am, you will notice, a pretty thorough sceptic about the project of phenomenology. What has it taught us? |
| 22210 | After everything is bracketed, consciousness still has a unique being of its own [Husserl] |
| Full Idea: We fix our eyes steadily upon the sphere of Consciousness and study what it is that we find immanent in it. ...Consciousness in itself has a being of its own which in its absolute uniqueness of nature remains unaffected by disconnection. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], II.2.033) | |
| A reaction: 'Disconnection' is his 'bracketing'. He makes it sound obvious, but Schopenhauer entirely disagrees with him, and I have no idea how to arbitrate. I struggle to grasp consciousness once nature has been bracketed, but have little luck. Is it Da-sein? |
| 22215 | Phenomenology describes consciousness, in the light of pure experiences [Husserl] |
| Full Idea: Phenomenology is a pure descriptive discipline which studies the whole field of pure transcendental consciousness in the light of pure intuition. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], II.4.059) | |
| A reaction: When he uses the word 'pure' three times in a sentence, each applied to a different thing, you begin to wonder precisely what it means. Strictly speaking, I would probably only apply 'pure' to abstracta, and never to experiences or reality.115 |
| 3348 | If phenomenology is deprived of the synthetic a priori, it is reduced to literature [Benardete,JA on Husserl] |
| Full Idea: Sternly envisaged by Husserl as a scientific discipline, phenomenology, on being stripped of the synthetic a priori by the logical positivists, ends up in Sartre as a largely literary undertaking. | |
| From: comment on Edmund Husserl (works [1898]) by José A. Benardete - Metaphysics: the logical approach Ch.18 |
| 15570 | Phenomenology is the science of essences - necessary universal structures for art, representation etc. [Husserl, by Polt] |
| Full Idea: For Husserl, phenomenology must seek the essential aspects of phenomena - necessary, universal structures, such as the essence of art or the essence of representation. He sought a science of these essences. | |
| From: report of Edmund Husserl (Logical Investigations [1900]) by Richard Polt - Heidegger: an introduction 2 'Dilthey' |
| 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. |
| 10882 | Predicative definitions only refer to entities outside the defined collection [Horsten] |
| Full Idea: Definitions are called 'predicative', and are considered sound, if they only refer to entities which exist independently from the defined collection. | |
| From: Leon Horsten (Philosophy of Mathematics [2007], §2.4) |
| 22201 | The use of mathematical-style definitions in philosophy is fruitless and harmful [Husserl] |
| Full Idea: Definition cannot take the same form in philosophy as it does in mathematics; the imitation of mathematical procedure is invariably in this respect not only unfruitful, but perverse and most harmful in its consequences. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], Intro) | |
| A reaction: A hundred years of analytic philosophy has entirely ignored this warning. My heart has always sunk when I read '=def...' in a philosophy article (which is usually American). The illusion of rigour. |
| 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. |
| 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? |
| 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) |
| 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. |
| 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) |
| 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. |
| 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) |
| 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) |
| 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) |
| 15350 | The Naïve Theory takes the bi-conditionals as axioms, but it is inconsistent, and allows the Liar [Horsten] |
| Full Idea: The Naïve 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). |
| 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) |
| 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) |
| 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) |
| 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. |
| 21222 | Logicians presuppose a world, and ignore logic/world connections, so their logic is impure [Husserl, by Velarde-Mayol] |
| Full Idea: Husserl maintained that because most logicians have not studied the connection between logic and the world, logic did not achieve its status of purity. Even more, their logic implicitly presupposed a world. | |
| From: report of Edmund Husserl (Formal and Transcendental Logic [1929]) by Victor Velarde-Mayol - On Husserl 4.5.1 | |
| A reaction: The point here is that the bracketing of phenomenology, to reach an understanding with no presuppositions, is impossible if you don't realise what your are presupposing. I think the logic/world relationship is badly neglected, thanks to Frege. |
| 21223 | Phenomenology grounds logic in subjective experience [Husserl, by Velarde-Mayol] |
| Full Idea: The phenomenological logic grounds logical notions in subjective acts of experience. | |
| From: report of Edmund Husserl (Formal and Transcendental Logic [1929], p.183) by Victor Velarde-Mayol - On Husserl 4.5.1 | |
| A reaction: I'll approach this with great caution, but this is a line of thought that appeals to me. The core assumptions of logic do not arise ex nihilo. |
| 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. |
| 10884 | A theory is 'categorical' if it has just one model up to isomorphism [Horsten] |
| Full Idea: If a theory has, up to isomorphism, exactly one model, then it is said to be 'categorical'. | |
| From: Leon Horsten (Philosophy of Mathematics [2007], §5.2) |
| 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? |
| 9837 | 0 is not a number, as it answers 'how many?' negatively [Husserl, by Dummett] |
| Full Idea: Husserl contends that 0 is not a number, on the grounds that 'nought' is a negative answer to the question 'how many?'. | |
| From: report of Edmund Husserl (Philosophy of Arithmetic [1894], p.144) by Michael Dummett - Frege philosophy of mathematics Ch.8 | |
| A reaction: I seem to be in a tiny minority in thinking that Husserl may have a good point. One apple is different from one orange, but no apples are the same as no oranges. That makes 0 a very peculiar number. See Idea 9838. |
| 9576 | Multiplicity in general is just one and one and one, etc. [Husserl] |
| Full Idea: Multiplicity in general is no more than something and something and something, etc.; ..or more briefly, one and one and one, etc. | |
| From: Edmund Husserl (Philosophy of Arithmetic [1894], p.85), quoted by Gottlob Frege - Review of Husserl's 'Phil of Arithmetic' | |
| A reaction: Frege goes on to attack this idea fairly convincingly. It seems obvious that it is hard to say that you have seventeen items, if the only numberical concept in your possession is 'one'. How would you distinguish 17 from 16? What makes the ones 'multiple'? |
| 17444 | Husserl said counting is more basic than Frege's one-one correspondence [Husserl, by Heck] |
| Full Idea: Husserl famously argued that one should not explain number in terms of equinumerosity (or one-one correspondence), but should explain equinumerosity in terms of sameness of number, which should be characterised in terms of counting. | |
| From: report of Edmund Husserl (Philosophy of Arithmetic [1894]) by Richard G. Heck - Cardinality, Counting and Equinumerosity 3 | |
| A reaction: [Heck admits he hasn't read the Husserl] I'm very sympathetic to Husserl, though nearly all modern thinking favours Frege. Counting connects numbers to their roots in the world. Mathematicians seem oblivious of such things. |
| 21224 | Pure mathematics is the relations between all possible objects, and is thus formal ontology [Husserl, by Velarde-Mayol] |
| Full Idea: Pure mathematics is the science of the relations between any object whatever (relation of whole to part, relation of equality, property, unity etc.). In this sense, pure mathematics is seen by Husserl as formal ontology. | |
| From: report of Edmund Husserl (Formal and Transcendental Logic [1929]) by Victor Velarde-Mayol - On Husserl 4.5.2 | |
| A reaction: I would expect most modern analytic philosophers to agree with this. Modern mathematics (e.g. category theory) seems to have moved beyond this stage, but I still like this idea. |
| 10885 | Computer proofs don't provide explanations [Horsten] |
| Full Idea: Mathematicians are uncomfortable with computerised proofs because a 'good' proof should do more than convince us that a certain statement is true. It should also explain why the statement in question holds. | |
| From: Leon Horsten (Philosophy of Mathematics [2007], §5.3) |
| 10881 | The concept of 'ordinal number' is set-theoretic, not arithmetical [Horsten] |
| Full Idea: The notion of an ordinal number is a set-theoretic, and hence non-arithmetical, concept. | |
| From: Leon Horsten (Philosophy of Mathematics [2007], §2.3) |
| 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. |
| 22209 | Our goal is to reveal a new hidden region of Being [Husserl] |
| Full Idea: We could refer to our goal as the winning of a new region of Being, the distinctive character of which has not yet been defined. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], II.2.033) | |
| A reaction: The obvious fruit of this idea, I would think, is Heidegger's concept of Da-sein, which claims to be a distinctively human region of Being. I'm not sure I can cope with the claim that Being itself (a very broad-brush term) has hidden regions. |
| 22211 | As a thing and its perception are separated, two modes of Being emerge [Husserl] |
| Full Idea: We are left with the transcendence of the thing over against the perception of it, ...and thus a basic and essential difference arises between Being as Experience and Being as Thing. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], II.2.042) | |
| A reaction: I'm thinking that this is not just the germ of Heidegger's concept of Da-sein, but it actually IS his concept, without the label. Husserl had said that he hoped to reveal a new region of Being. |
| 21226 | Husserl sees the ego as a monad, unifying presence, sense and intentional acts [Husserl, by Velarde-Mayol] |
| Full Idea: Husserl's notion of monad expresses a complete inegration of every intentional presence into its sense, and every sense into the intentional acts, ....and finally every intentional act is integrated into the ego. | |
| From: report of Edmund Husserl (Cartesian Meditations [1931]) by Victor Velarde-Mayol - On Husserl 4.6.2 | |
| A reaction: No, I don't understand that either, but it makes good sense to employ the concept of a 'monad' into the concept of the ego, if you think it embodies perfect unity. That was a main motivation for Leibniz to employ the word. |
| 22202 | The World is all experiencable objects [Husserl] |
| Full Idea: The World is the totality of objects that can be known through experience. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], I.1.001) | |
| A reaction: I think this is the 'Nature' which has to be 'bracketed', when pursuing Phenomenology. It sounds like anti-realist empiricism, which has no place for unobservables. |
| 22213 | Absolute reality is an absurdity [Husserl] |
| Full Idea: An absolute reality is just as valid as a round square. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], II.3.055) | |
| A reaction: Husserl distances himself from 'Berkeleyian' idealism, but his discussion keeps flirting with, perhaps in some sort of have-your-cake-and-eat-it Hegelian way. Perhaps it is close to Dummett's Anti-Realism. |
| 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. |
| 21218 | The sense of anything contingent has a purely apprehensible essence or Eidos [Husserl] |
| Full Idea: It belongs to the sense of anything contingent to have an essence and therefore an Eidos which can be apprehended purely. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], I.1.002), quoted by Victor Velarde-Mayol - On Husserl 3.2.2 | |
| A reaction: This is the quirky idea that we can know necessary categorial essences a priori, even if the category is currently empty. Crops us in Lowe. Husserl says grasping the corresponding individuals must be possible. Third Man question. |
| 19263 | Imagine an object's properties varying; the ones that won't vary are the essential ones [Husserl, by Vaidya] |
| Full Idea: Husserl's 'eidetic variation' implies that we can judge the essential properties of an object by varying the properties of the object in imagination, and seeing which vary and which do not. | |
| From: report of Edmund Husserl (Ideas: intro to pure phenomenology [1913]) by Anand Vaidya - Understanding and Essence 'Knowledge' | |
| A reaction: The problem with this is that there are trivial or highly general necessary properties which are obviously not essential to the thing. Vaidya says [822] you can't perform the experiment without prior knowledge of the essence. |
| 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) |
| 21220 | The physical given, unlike the mental given, could be non-existing [Husserl] |
| Full Idea: Anything physical which is given in person can be non-existing, no mental process which is given in person can be non-existing. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], II.2.046), quoted by Victor Velarde-Mayol - On Husserl 3.3.5 | |
| A reaction: This endorsement of Descartes shows how strong the influence of the Cogito remained in later continental philosophy. Phenomenology is a footnote to Descartes. |
| 21216 | Husserl says we have intellectual intuitions (of categories), as well as of the senses [Husserl, by Velarde-Mayol] |
| Full Idea: The novelty of Husserl is to describe that we have intellectual intuitions, intuitions of categories as we have intuitions of sense objects. | |
| From: report of Edmund Husserl (Logical Investigations [1900], II.VI.24) by Victor Velarde-Mayol - On Husserl 2.4.4 | |
| A reaction: This is 'intuitions' in Kant's sense, of something like direct apprehensions. This idea is an axiom of phenomenology, because all mental life must be bracketed, and not just the sense experience part. |
| 22205 | Feelings of self-evidence (and necessity) are just the inventions of theory [Husserl] |
| Full Idea: So-called feelings of self-evidence, of intellectual necessity, and however they may otherwise be called, are just theoretically invented feelings. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], I.2.021) | |
| A reaction: This seems to be a dismissal of the a priori necessary on the grounds that it is 'theory-laden' - which is why it has to be bracketed in order to do phenomenology. |
| 21221 | Direct 'seeing' by consciousness is the ultimate rational legitimation [Husserl] |
| Full Idea: Immediate 'seeing', not merely sensuous, experiential seeing, but seeing in the universal sense as an originally presenting consciousness of any kind whatsoever, is the ultimate legitimising source of all rational assertions. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], I.2.019), quoted by Victor Velarde-Mayol - On Husserl 3.3.5 | |
| A reaction: Husserl is (I gather from this) a classic rationalist. Just like Descartes' judgement of the molten wax. |
| 22220 | The phenomena of memory are given in the present, but as being past [Husserl, by Bernet] |
| Full Idea: In Husserl's phenomenology, the intentional object of a memory is the object of a past experience, which is intuitively given to me in the present, not, however, as being present but as being past. | |
| From: report of Edmund Husserl (Ideas: intro to pure phenomenology [1913]) by Rudolf Bernet - Husserl p.203 | |
| A reaction: I certainly don't have to assess my mental events, and judge which are past, which are now, and which are future imaginings. I suppose Fodor would say they are memories because we find them in the memory-box. How else could it work? |
| 22206 | Natural science has become great by just ignoring ancient scepticism [Husserl] |
| Full Idea: Natural science has grown to greatness by pushing ruthlessly aside the rank growth of ancient skepticism and renouncing the attempt to conquer it. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], I.2.026) | |
| A reaction: This may be because scepticism is boring, or it may be because science 'brackets' scepticism, leaving philosophers to worry about it. |
| 22221 | We know another's mind via bodily expression, while also knowing it is inaccessible [Husserl, by Bernet] |
| Full Idea: Another person's consciousness is given to me through the expressive stratum of her body, which gives me access to her experience while making me realise that it is inaccessible to me. Empathy is a presentation of what is absent. | |
| From: report of Edmund Husserl (Ideas: intro to pure phenomenology [1913]) by Rudolf Bernet - Husserl p.203 | |
| A reaction: This is the phenomenological approach to the problem of other minds, by examining the raw experience of encountering another person. It is true that we seem to both know and not know another person's mind when we encounter them. |
| 21228 | Husserl's monads (egos) communicate, through acts of empathy. [Husserl, by Velarde-Mayol] |
| Full Idea: For Husserl monads have windows because they communicate with each other. The windows of the monads are the acts of empathy. | |
| From: report of Edmund Husserl (Cartesian Meditations [1931]) by Victor Velarde-Mayol - On Husserl 4.7.5 | |
| A reaction: Leibniz said his monads (which include minds) have 'no windows'. The mere existence of empathy (or mirror neurons, as we would say) is hardly sufficient to defeat solipsism. |
| 22212 | Pure consciousness is a sealed off system of actual Being [Husserl] |
| Full Idea: Consciousness, considered in its 'purity', must be reckoned as a self-contained system of Being, a system of actual Being, into which nothing can penetrate, and from which nothing can escape. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], II.3.049) | |
| A reaction: Recorded without comment, to show that among phenomenologists there is a way of thinking about consciousness which is a long way from analytic discussions of the topic. |
| 9575 | Husserl identifies a positive mental act of unification, and a negative mental act for differences [Husserl, by Frege] |
| Full Idea: Husserl identifies a 'unitary mental act' where several contents are connected or related to one another, and also a difference-relation where two contents are related to one another by a negative judgement. | |
| From: report of Edmund Husserl (Philosophy of Arithmetic [1894], p.73-74) by Gottlob Frege - Review of Husserl's 'Phil of Arithmetic' p.322 | |
| A reaction: Frege is setting this up ready for a fairly vicious attack. Where Hume has a faculty for spotting resemblances, it is not implausible that we should also be hard-wired to spot differences. 'You look different; have you changed your hair style?' |
| 21225 | The psychological ego is worldly, and the pure ego follows transcendental reduction [Husserl, by Velarde-Mayol] |
| Full Idea: Husserl distinguishes two sorts of egos or subjects of experience, the psychological ego and the pure ego. The psychological ego is a reality of the world, and the pure ego is a result of transcendental reduction. | |
| From: report of Edmund Husserl (Cartesian Meditations [1931]) by Victor Velarde-Mayol - On Husserl 4.6.1 | |
| A reaction: The sounds like embracing both the Cartesian and the Kantian egos. This is obviously the source of Sartre's interesting early book on the self. 'Transcendental reduction' is his bracketing or epoché. |
| 22214 | We never meet the Ego, as part of experience, or as left over from experience [Husserl] |
| Full Idea: We never stumble across the pure Ego as an experience within the flux of manifold experiences which survives as transcendental residuum; nor do we meet it as a constitutive bit of experience appearing with the experience of which it is an integral part. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], II.4.057) | |
| A reaction: It seems that he agrees with David Hume. Sartre's 'Transcendence of the Ego' follows up this idea. However, Husserl goes on to assert the 'necessity' of the permanent Ego, which sounds like Kant's view. |
| 21214 | We clarify concepts (e.g. numbers) by determining their psychological origin [Husserl, by Velarde-Mayol] |
| Full Idea: Husserl said that the clarification of any concept is made by determining its psychological origin. He is concerned with the psychological origins of the operation of calculating cardinal numbers. | |
| From: report of Edmund Husserl (Philosophy of Arithmetic [1894]) by Victor Velarde-Mayol - On Husserl 2.2 | |
| A reaction: This may not be the same as the 'psychologism' that Frege so despised, because Husserl is offering a clarification, rather than the intrinsic nature of number concepts. It is not a theory of the origin of numbers. |
| 9819 | Psychologism blunders in focusing on concept-formation instead of delineating the concepts [Dummett on Husserl] |
| Full Idea: Husserl substitutes his account of the process of concept-formation for a delineation of the concept. It is above all in making this substitution that psychologism is objectionable (and Frege opposed it so vehemently). | |
| From: comment on Edmund Husserl (Philosophy of Arithmetic [1894]) by Michael Dummett - Frege philosophy of mathematics Ch.2 | |
| A reaction: While this is a powerful point which is a modern orthodoxy, it hardly excludes a study of concept-formation from being of great interest for other reasons. It may not appeal to logicians, but it is crucial part of the metaphysics of nature. |
| 9851 | Husserl wanted to keep a shadowy remnant of abstracted objects, to correlate them [Dummett on Husserl] |
| Full Idea: Husserl saw that abstracted units, though featureless, must in some way retain their distinctness, some shadowy remnant of their objects. So he wanted to correlate like-numbered sets, not just register their identity, but then abstractionism fails. | |
| From: comment on Edmund Husserl (Philosophy of Arithmetic [1894]) by Michael Dummett - Frege philosophy of mathematics Ch.12 | |
| A reaction: Abstractionism is held to be between the devil and the deep blue sea, of depending on units which are identifiable, when they are defined as devoid of all individuality. We seem forced to say that the only distinction between them is countability. |
| 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... |
| 22203 | Only facts follow from facts [Husserl] |
| Full Idea: From facts follow always nothing but facts. | |
| From: Edmund Husserl (Ideas: intro to pure phenomenology [1913], I.1.008) | |
| A reaction: I presume objective possibilities follow from facts, so this doesn't sound strictly correct. I sounds like a nice slogan for those desiring to keep facts separate from values. [on p.53 he comments on fact/value] |
| 21898 | For existentialists the present is empty without the pull of the future and weight of the past [May] |
| Full Idea: For the existential view of lived time, the present would be empty if it were not for the pull of the future and the weight of the past that give it its character. | |
| From: Todd May (Gilles Deleuze [2006], 2.05) | |
| A reaction: Bergson seems to be important in developing this idea, though I suspect that Kierkegaard is a source. |
| 21905 | Liberal theory starts from the governed, not from the governor [May] |
| Full Idea: For liberal theory, it is the individual to be governed, not the governor, who is the starting point. | |
| From: Todd May (Gilles Deleuze [2006], 4.02) | |
| A reaction: I'm inclined to see this as the single-handed achievement of Thomas Hobbes, who starts from the need of citizens to secure their contracts. Plato's society starts from entrepreneurs, but their need for a ruler seems a priori. |