96 ideas
| 18730 | The history of philosophy only matters if the subject is a choice between rival theories [Wittgenstein] |
| Full Idea: If philosophy were a matter of choice between rival theories, then it would be sound to teach it historically. But if it is not, then it is a fault to teach it historically, because it is quite unnecessary; we can tackle the subject direct. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], C V A) | |
| A reaction: Wittgenstein was a bit notorious for not knowing the history of the subject terribly well, and this explains why. Presumably our tackling the subject direct will not have the dreadful consequence of producing yet another theory. |
| 18704 | Philosophy tries to be rid of certain intellectual puzzles, irrelevant to daily life [Wittgenstein] |
| Full Idea: Philosophy is the attempt to be rid of a particular kind of puzzlement. This 'philosophical' puzzlement is one of the intellect and not of instinct. Philosophical puzzles are irrelevant to our every-day life. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], A I.1) | |
| A reaction: All enquiry begins with puzzles, and they are cured by explanations, which result in understanding. In that sense he is right. I entirely disagree that the puzzles are irrelevant to daily life. |
| 18710 | Philosophers express puzzlement, but don't clearly state the puzzle [Wittgenstein] |
| Full Idea: Philosophers as 'Why?' and 'What?' without knowing clearly what their questions are. They are expressing a feeling of mental uneasiness. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B I.1) | |
| A reaction: He suggests it is childish to express puzzlement, instead of asking for precise information. How odd. All enquiries start with vague puzzlement, which gradually comes into focus, or else is abandoned. |
| 18732 | We don't need a theory of truth, because we use the word perfectly well [Wittgenstein] |
| Full Idea: It is nonsense to try to find a theory of truth, because we can see that in everyday life we use the word quite clearly and definitely in various different senses. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], C V B) | |
| A reaction: This was a year before Tarski published his famous theory of truth for formal languages. Prior to that, most philosophers were giving up on truth. Would he say the same about 'gravity' or 'inflation'? |
| 18714 | We already know what we want to know, and analysis gives us no new facts [Wittgenstein] |
| Full Idea: In philosophy we know already all that we want to know; philosophical analysis does not give us any new facts. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B V.1) |
| 3807 | Reason is and ought to be the slave of the passions [Hume] |
| Full Idea: Reason is and ought to be the slave of the passions, and can never pretend to any other office than to serve and obey them. | |
| From: David Hume (Treatise of Human Nature [1739], II.III.3) |
| 18706 | Words of the same kind can be substituted in a proposition without producing nonsense [Wittgenstein] |
| Full Idea: 'Blue' and 'brown' are of the same kind, for the substitution of one for the other, though it may falsify the proposition, does not make nonsense of it. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], A I.4) | |
| A reaction: He chooses an easy example, because they are determinates of the determinable 'coloured'. What if I say 'the sky is blue', and then substitute 'frightening' for 'blue'? |
| 18735 | Talking nonsense is not following the rules [Wittgenstein] |
| Full Idea: Talking nonsense is not following the rules. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], C X) | |
| A reaction: He doesn't seem to distinguish between syntax and semantics, and makes it sound as if all nonsense is syntactic, which it isn't. |
| 18719 | Grammar says that saying 'sound is red' is not false, but nonsense [Wittgenstein] |
| Full Idea: If grammar says that you cannot say that a sound is red, it means not that it is false to say so but that it is nonsense - i.e. not a language at all. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B IX.6) | |
| A reaction: I am baffled as to why he thinks 'grammar' is what prohibits such a statement. Surely the world, the nature of sound and colour, is what makes the application of the predicate wrong. Sounds aren't coloured, so they can't be red. False, not nonsense. |
| 18731 | There is no theory of truth, because it isn't a concept [Wittgenstein] |
| Full Idea: It is wrong to say that there is any one theory of truth, for truth is not a concept. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], C V B) | |
| A reaction: This makes you wonder how he understood the word 'concept'. In most modern discussions truth seems to be a concept, and in Frege it can be an unsaturated predicate which is satisfied by sentences or thoughts. |
| 18707 | All thought has the logical form of reality [Wittgenstein] |
| Full Idea: Thought must have the logical form of reality if it is to be thought at all. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], A V.1) | |
| A reaction: This links nicely the idea that true thoughts somehow share the structure of what they refer to, with the idea of logical form in logic. But maybe logical form is a fiction we offer in order to obtain a spurious map of reality. |
| 18724 | In logic nothing is hidden [Wittgenstein] |
| Full Idea: In logic nothing is hidden. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B XII.3) | |
| A reaction: If so, then the essence of logic must be there for all to see. The rules of natural deduction are a good shot at showing this. |
| 18709 | Laws of logic are like laws of chess - if you change them, it's just a different game [Wittgenstein] |
| Full Idea: I might as well question the laws of logic as the laws of chess. If I change the rules it is a different game and there is an end of it. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], A XI.3) | |
| A reaction: No, that isn't the end of it, because there are meta-criteria for preferring one game to another. Why don't we just give up classical logic? It would be such fun to have a wild wacky logic. We can start with 'tonk'. |
| 18736 | Contradiction is between two rules, not between rule and reality [Wittgenstein] |
| Full Idea: Contradiction is between one rule and another, not between rule and reality. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], C XIII) | |
| A reaction: If I say 'he is sitting' and 'he is standing', it seems to be reality which produces the contradiction. What 'rule' could possibly do it? The rule which says sitting and standing are incompatible? But what makes that so? |
| 18723 | We may correctly use 'not' without making the rule explicit [Wittgenstein] |
| Full Idea: Correct use does not imply the ability to make the rules explicit. Understanding 'not' is like understanding a move in chess. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B XII.1) |
| 18718 | Saying 'and' has meaning is just saying it works in a sentence [Wittgenstein] |
| Full Idea: When we say that the word 'and' has meaning what we mean is that it works in a sentence and is not just a flourish. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B VIII.2) |
| 18727 | A person's name doesn't mean their body; bodies don't sit down, and their existence can be denied [Wittgenstein] |
| Full Idea: The meaning of the words 'Professor Moore' is not a certain human body, because we do not say that the meaning sits on the sofa, and the words occur in the proposition 'Professor Moore does not exist'. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B Easter) | |
| A reaction: Brilliant. Love it. Kripke ending up denying the existence of 'meanings'. |
| 18738 | We don't get 'nearer' to something by adding decimals to 1.1412... (root-2) [Wittgenstein] |
| Full Idea: We say we get nearer to root-2 by adding further figures after the decimal point: 1.1412.... This suggests there is something we can get nearer to, but the analogy is a false one. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], Notes) |
| 18708 | Infinity is not a number, so doesn't say how many; it is the property of a law [Wittgenstein] |
| Full Idea: 'Infinite' is not an answer to the question 'How many?', since the infinite is not a number. ...Infinity is the property of a law, not of an extension. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], A VII.2) |
| 8649 | Two numbers are equal if all of their units correspond to one another [Hume] |
| Full Idea: When two numbers are so combin'd, as that the one has always a unit answering to every unit of the other, we pronounce them equal. | |
| From: David Hume (Treatise of Human Nature [1739], I.III.1) | |
| A reaction: This became known as Hume's Principle after Frege made use of it for logicism (Foundations §63). It reduces equality to something fairly simple and visual (one-to-one correspondence). But we also say that two logicians or musicians are 'equal' in ability. |
| 21291 | There is no medium state between existence and non-existence [Hume] |
| Full Idea: Betwixt unity and number there can be no medium; no more than betwixt existence and non-existence. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.2) | |
| A reaction: Just to confirm that, as you would expect, the great empiricist has no time for 'subsistence', or shadows and holes having lower grade existece. |
| 18737 | There are no positive or negative facts; these are just the forms of propositions [Wittgenstein] |
| Full Idea: There are no positive or negative facts. 'Positive' and 'negative' refer to the form of propositions, and not to the facts which verify or falsify them. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], C XIII) | |
| A reaction: Personally I think if we are going to allow the world to be full of 'facts', then there are negative, conjunctive, disjunctive and hypothetical facts. |
| 11942 | Power is the possibility of action, as discovered by experience [Hume] |
| Full Idea: Power consists in the possibility or probability of any action, as discovered by experience and the practice of the world. | |
| From: David Hume (Treatise of Human Nature [1739], p.313), quoted by George Molnar - Powers 5 | |
| A reaction: [page in OUP edn] This strikes me as blatantly false, and typical of those who confuse epistemology with ontology. It implies that a power that takes everyone by surprise is impossible, by definition. |
| 11949 | There may well be powers in things, with which we are quite unacquainted [Hume] |
| Full Idea: I am, indeed, ready to allow, that there may be several qualities both in material and immaterial objects, with which we are utterly unacquainted; and if we please to call these powers and efficiency, 'twill be be of little consequence to the world. | |
| From: David Hume (Treatise of Human Nature [1739], p.168), quoted by George Molnar - Powers 7.2.1 | |
| A reaction: A delightful air of casual indifference. What the classic empiricists needed was a notion of 'best explanation', which would allow them to leap beyond immediate experience. They made plenty of other leaps beyond experience, though Hume hated them. |
| 11950 | We have no idea of powers, because we have no impressions of them [Hume] |
| Full Idea: We never have any impression that contains any power or efficacy. We never therefore have any idea of power. | |
| From: David Hume (Treatise of Human Nature [1739], p.161), quoted by George Molnar - Powers 7.2.1 | |
| A reaction: [page in Selby-Bigges edn] It seems to me plausible that Hume is utterly wrong, because our own mental lives are a direct and constant experience of the physical powers and efficacies of material objects. |
| 11941 | The distinction between a power and its exercise is entirely frivolous [Hume] |
| Full Idea: The distinction which we sometimes make betwixt a power and the exercise of it is entirely frivolous, and ... neither man nor any other being ought ever to be thought possesst of any ability, unless it be exerted and put into action. | |
| From: David Hume (Treatise of Human Nature [1739], p.311), quoted by George Molnar - Powers 5 | |
| A reaction: [page in OUP] Molnar says this strong intuition is shared by most of us, but I take the world to be full of people who can play the piano or speak Spanish, but never actually do it. [but see Idea 11942] Most wasps never sting anything. |
| 18715 | Using 'green' is a commitment to future usage of 'green' [Wittgenstein] |
| Full Idea: If I say this is green, I must say that other things are green too. I am committed to a future usage. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B VI.2) | |
| A reaction: This seems to suggest that the eternal verity of a universal concept is just a convention of stability in a language. |
| 11098 | Momentary impressions are wrongly identified with one another on the basis of resemblance [Hume, by Quine] |
| Full Idea: Momentary impressions, according to Hume, are wrongly identified with one another on the basis of resemblance. | |
| From: report of David Hume (Treatise of Human Nature [1739]) by Willard Quine - Identity, Ostension, and Hypostasis 3 | |
| A reaction: I don't have a Hume quotation for this yet, but Quine is plausibly claiming Hume as a resemblance nominalist, equipped with an error theory about universals. |
| 7954 | If we see a resemblance among objects, we apply the same name to them, despite their differences [Hume] |
| Full Idea: When we have found a resemblance among several objects, that often occur to us, we apply the same name to all of them, whatever differences we may observe in the degrees of their quantity and quality, and whatever other differences may appear among them. | |
| From: David Hume (Treatise of Human Nature [1739], I.I.7) | |
| A reaction: This must to some extent by right, whatever objections can be found. Russell's objection (Idea 4441) wouldn't alter the truth of Hume's observation, thought Hume is attacking universals and Russell defending them. |
| 21293 | Individuation is only seeing that a thing is stable and continuous over time [Hume] |
| Full Idea: The principle of individuation is nothing but the invariableness and uninterruptedness of any object through a supposed variation of time, by which the mind can trace it in the different periods of its existence. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.2) | |
| A reaction: Not convinced by this. I can individuate something by an almost instantaneous glimpse. I don't increasingly individuate it as time passes. Instant viewing of type and structure may be enough. |
| 12048 | The only meaning we have for substance is a collection of qualities [Hume] |
| Full Idea: We have no idea of substance, distinct from that of a collection of particular qualities, nor have we any other meaning when we either talk or reason concerning it. | |
| From: David Hume (Treatise of Human Nature [1739], I.I.6) | |
| A reaction: This is the standard empiricist view of such things, firmly stated. It is tempting to say that Hume has simply misunderstood the word, since it is precisely intended to mean not the qualities, but what underlies them, and persists. |
| 13424 | Aristotelians propose accidents supported by substance, but they don't understand either of them [Hume] |
| Full Idea: The peripatetic philosophers carry their fictions still further, and both suppose a substance supporting, which they do not understand, and an accident supported, of which they have as imperfect an idea. The whole system is entirely incomprehensible. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.3) | |
| A reaction: It seems to me that if you put it to Aristotle that he didn't understand 'substantial form', he would concede the point, but nevertheless say that it was ideal at which knowledge aimed. Locke is much more astute than Hume on this. |
| 21300 | A change more obviously destroys an identity if it is quick and observed [Hume] |
| Full Idea: A change in any considerable part of a body destroys its identity; but 'tis remarkable that where the change is produced gradually and insensibly we are less apt to ascribe to it the same effect. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: Broad spotted that landscapes change too, but so slowly that we barely admit any change at all. The type of change also matters. If my car slowly changes to chocolate the speed of change is a minor factor. |
| 21299 | Changing a part can change the whole, not absolutely, but by its proportion of the whole [Hume] |
| Full Idea: Though the change of any considerable part of a mass of matter destroys the identity of the whole, yet we must measure the greatness of the part, not absolutely, but by its proportion to the whole. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: This seems to nicely demonstrate that the wholeness is in the mind of the perceiver, and does not simply depend on objective facts. Compare the proportion needed to change my pile of mud and my pile of gold. |
| 1321 | If identity survives change or interruption, then resemblance, contiguity or causation must unite the parts of it [Hume] |
| Full Idea: The objects which are variable or interrupted, and yet are supposed to continue the same, are such only as consist of a succession of parts, connected together by resemblance, contiguity, or causation. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) |
| 1330 | If a republic can retain identity through many changes, so can an individual [Hume] |
| Full Idea: As the same individual republic may not only change its members, but also its laws and constitutions; in like manner the same person may vary his character and disposition, as well as his impressions and ideas, without losing his identity. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) |
| 21302 | If a ruined church is rebuilt, its relation to its parish makes it the same church [Hume] |
| Full Idea: If a church which was formerly of brick fell to ruin, the parish can build the same church of free-stone, with modern architecture. Neither the form nor materials are the same, but their relation to the parishioners is sufficient to say they are the same. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: The clearly invites the question of whether this is type-identity or token-identity. If the parish decided they wanted two churches they obviously wouldn't be the same (even if they then demolished the first one). |
| 21303 | We accept the identity of a river through change, because it is the river's nature [Hume] |
| Full Idea: Where the objects are in their nature changeable and inconstant, we admit of a more sudden transition. The nature of a river consists in the motion and change of parts. What is expected appears of less moment than what is unusual and extraordinary. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: Aha! Little does Hume realise how Aristotelian he is! Aristotle may have a more objective view of the 'nature' of a thing, but making inferences about identity over time from a thing's essential nature is pure Aristotle. |
| 21301 | The purpose of the ship makes it the same one through all variations [Hume] |
| Full Idea: The common end [of a ship], in which the parts conspire, is the same under all variations, and affords an easy transition of the imagination from one situation of the body to another. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: It is not true that a ship remains the same under ALL variations. Consider gradually changing a yacht into a racing powerboat. You might say the purpose is then changed, but the slight variations in a yacht can slightly change its purpose. |
| 21290 | Multiple objects cannot convey identity, because we see them as different [Hume] |
| Full Idea: A mutiplicity of objects can never convey the idea of identity. The mind always pronounces the one not to be the other. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.2) | |
| A reaction: However, if we are talking on the phone about two objects we are viewing, such as two buildings, our descriptions might lead us to conclude that our objects are identical. Thus experience might imply identity. |
| 1207 | Both number and unity are incompatible with the relation of identity [Hume] |
| Full Idea: Both number and unity are incompatible with the relation of identity. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.2) |
| 21289 | 'An object is the same with itself' is meaningless; it expresses unity, not identity [Hume] |
| Full Idea: In that proposition 'an object is the same with itself', if the idea expressed by the word 'object' were no way distinguished from that meant by 'itself', we should really mean nothing. ...One single object conveys the idea of unity, not that of identity. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.2) | |
| A reaction: As far as I can see it is mathematicians who like self-identity, to justify x=x, which they need. To say 'this vase is identical with itself' is an empty locution. It expresses either unity or stability over time. See Idea 21292. |
| 21292 | Saying an object is the same with itself is only meaningful over a period of time [Hume] |
| Full Idea: We cannot, in any propriety of speech, say that an object is the same with itself, unless we mean that the object existent at one time is the same with itself at another time. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.2) | |
| A reaction: This seems correct, but the strict language of identity is superfluous when identifying stolen goods. 'This is my watch', not 'this watch is identical with my watch'. |
| 9428 | Nothing we clearly imagine is absolutely impossible [Hume] |
| Full Idea: 'Tis an established maxim in metaphysics, that whatever the mind clearly conceives includes the idea of possible existence, or in other words, that nothing we imagine is absolutely impossible. | |
| From: David Hume (Treatise of Human Nature [1739], I.II.2) | |
| A reaction: It is important to note that this empiricist approach to what is impossible requires that we 'clearly' conceive the possibility - but how do we evaluate whether we are being clear or not? |
| 4766 | Necessity only exists in the mind, and not in objects [Hume] |
| Full Idea: Necessity …is nothing but an internal impression of the mind, or a determination to carry our thoughts from one object to another. | |
| From: David Hume (Treatise of Human Nature [1739], I.III.16) | |
| A reaction: The classic statement of the empiricist position. Personally I don't believe it. Non-mental necessities are likely to be natural, or to be features of 'Platonic' objects. A big issue… |
| 18726 | For each necessity in the world there is an arbitrary rule of language [Wittgenstein] |
| Full Idea: To a necessity in the world there corresponds an arbitrary rule in language. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B XIV.2) | |
| A reaction: This seems to be hardcore logical positivism, making all necessities arbitrary. Compare Quine on the number of planets. |
| 18712 | Understanding is translation, into action or into other symbols [Wittgenstein] |
| Full Idea: Understanding is really translation, whether into other symbols or into action. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B I.5) | |
| A reaction: The second part of this sounds like pure pragmatism. To do is to understand? I doubt it. Do animals understand anything? |
| 6526 | Hume says objects are not a construction, but an imaginative leap [Hume, by Robinson,H] |
| Full Idea: Hume's idea is that we move from private impressions to the physical world, not by an unconscious analytical construction but by a spontaneous imaginative leap. | |
| From: report of David Hume (Treatise of Human Nature [1739]) by Howard Robinson - Perception IX.6 | |
| A reaction: The idea that objects are 'constructions' seems to have originated with Russell. Hume seems closer to the actual process, which is virtually instantaneous. They both forget that you can follow up the construction or leap with a cool evaluation. |
| 18280 | We live in sense-data, but talk about physical objects [Wittgenstein] |
| Full Idea: The world we live in is the world of sense-data, but the world we talk about is the world of physical objects. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], p.82), quoted by J. Alberto Coffa - The Semantic Tradition from Kant to Carnap 13 'Verif' | |
| A reaction: I really like that one. Even animals, I surmise, think of objects quite differently from the way they immediately experience them. |
| 18729 | Part of what we mean by stating the facts is the way we tend to experience them [Wittgenstein] |
| Full Idea: There is no need of a theory to reconcile what we know about sense data and what we believe about physical objects, because part of what we mean by saying that a penny is round is that we see it as elliptical in such and such conditions. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], C III) | |
| A reaction: This is an interesting and cunning move to bridge the gap between our representations and reallity. We may surmise how a thing really is, but then be surprised by the sense-data we get from it. |
| 6489 | Associationism results from having to explain intentionality just with sense-data [Robinson,H on Hume] |
| Full Idea: The limited theories of Berkeley and Hume have to be reductive, because they have to explain intentionality in terms of some kind of relation between sense-data; this predicament gives rise to the associationist accounts of psychology and meaning. | |
| From: comment on David Hume (Treatise of Human Nature [1739]) by Howard Robinson - Perception 1.4 | |
| A reaction: An illuminating explanation. Robinson seems to be implying that we should accept something like Searle's 'intrinsic' intentionality as basic, rather than intentionality built up from smaller components as Hume and Dennett suggest. |
| 6182 | Even Hume didn't include mathematics in his empiricism [Hume, by Kant] |
| Full Idea: Even Hume did not make empiricism so universal as to include mathematics in it. | |
| From: report of David Hume (Treatise of Human Nature [1739]) by Immanuel Kant - Critique of Practical Reason Pref | |
| A reaction: Hume didn't actually exclude mathematics, and the notion of 'relations of ideas' is a pointer. Subsequent empiricist have offered promising accounts. Personally I like the idea that patterns are the key idea. |
| 18734 | If you remember wrongly, then there must be some other criterion than your remembering [Wittgenstein] |
| Full Idea: If you remember wrongly, then there must be some other criterion than your remembering. If you admit another test, then your memory itself is not the test. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], C VII) | |
| A reaction: If I fear that I am remembering some private solitary event wrongly, there is no other criterion to turn to, so I'm stuck. Sometimes dubious memories are all we have. |
| 12417 | Mathematicians only accept their own proofs when everyone confims them [Hume] |
| Full Idea: There is no Mathematician so expert as to place entire confidence in any truth upon his discovery of it. ..Every time he runs over his proofs his confidence encreases, ..and is rais'd to perfection by the applause of the learned world. | |
| From: David Hume (Treatise of Human Nature [1739], IV.1.4) | |
| A reaction: [compressed] Quoted by Kitcher, and a nice example of the social nature of 'warrants', even in mathematics. It was illustrated well in the 1990s by the story of the proof of Fermat's Last Theorem by Andrew Wiles. |
| 5548 | Hume became a total sceptic, because he believed that reason was a deception [Hume, by Kant] |
| Full Idea: David Hume gave way entirely to scepticism, since he believed himself to have discovered in what is generally held to be reason a deception of our faculty of cognition. | |
| From: report of David Hume (Treatise of Human Nature [1739]) by Immanuel Kant - Critique of Pure Reason B128 | |
| A reaction: Unfair to Hume, who was very opposed to global scepticism (see Ideas 2240 and 2241), and voted only for 'mitigated scepticism' (see Idea 2242). On the other hand, there is no greater opposition in philosophy than Kant and Hume on 'pure reason'. |
| 7446 | The idea of inductive evidence, around 1660, made Hume's problem possible [Hume, by Hacking] |
| Full Idea: Hume's sceptical problem of induction could not have arisen much before 1660, for there was no concept of inductive evidence in terms of which to raise it. | |
| From: report of David Hume (Treatise of Human Nature [1739]) by Ian Hacking - The Emergence of Probability Cont 19 | |
| A reaction: Hacking is the expert, but Ideas 1683 and 1886 suggest there was some thinking on the problem in the ancient world. The worry about whether the future would be like the past must occasionally have bothered someone. |
| 18721 | Explanation and understanding are the same [Wittgenstein] |
| Full Idea: For us explanation and understanding are the same, understanding being the correlate of explanation. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B XI.2) | |
| A reaction: I'm not convinced that they are 'the same', but they are almost interdependent ideas. Strevens has a nice paper on this. |
| 18720 | Explanation gives understanding by revealing the full multiplicity of the thing [Wittgenstein] |
| Full Idea: An explanation gives understanding, ...but it cannot teach you understanding, it cannot create understanding. It makes further distinctions i.e. it increases multiplicity. When multiplicity is complete, then there is no further misunderstanding. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B X.3) | |
| A reaction: The thought seems to resemble Aristotle's idea of definition as gradual division of the subject. To understand is the dismantle the parts and lay them out before us. Wittgenstein was very interested in explanation at this time. |
| 18716 | A machine strikes us as being a rule of movement [Wittgenstein] |
| Full Idea: We are accustomed to look on a machine as the expression of a rule of movement. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B VII.2) | |
| A reaction: What a beautiful definition of a machine! I like this because it connects the two halves of my view of the 'essence' of a thing, as derived from Aristotle, as both a causal mechanism and an underlying principle. Cf Turing machines. |
| 18713 | If an explanation is good, the symbol is used properly in the future [Wittgenstein] |
| Full Idea: The criterion of an explanation is whether the symbol explained is used properly in the future. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B II.4) | |
| A reaction: This appears to be a pragmatic criterion for the best explanation. It presumably rests on his doctrine that meaning is use, so good explanation is understanding meanings. |
| 21806 | Memory, senses and understanding are all founded on the imagination [Hume] |
| Full Idea: The memory, senses, and understanding are all of them founded on the imagination, or the vivacity of our ideas. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.7.3), quoted by Stephan Schmid - Faculties in Early Modern Philosophy 5 | |
| A reaction: He seems to have in mind his theory of associations, which are not rational. |
| 3819 | Hume's 'bundle' won't distinguish one mind with ten experiences from ten minds [Searle on Hume] |
| Full Idea: Hume's thought that each perception is separate and distinct cannot be right, because then we can't distinguish between one consciousness with ten experiences and ten different consciousnesses. | |
| From: comment on David Hume (Treatise of Human Nature [1739]) by John Searle - Rationality in Action Ch.3.VI | |
| A reaction: Why can't the only connection between them be that they all occur to the speaker who reports to them? How would I know if one of 'my' mental events actually belonged to a neighbour and had strayed. If it was coherent, I would accept it. |
| 1317 | A person is just a fast-moving bundle of perceptions [Hume] |
| Full Idea: I affirm of the rest of mankind, that they are nothing but a bundle or collection of different perceptions, which succeed each other with an inconceivable rapidity, and are in perpetual flux and movement. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: Note that Hume is not just saying what we can know of ourselves, but is asserting a view of what we actually are. The minimal objection to this is to ask how we know that a perception is a member of one big bundle rather than several small ones. |
| 1331 | The parts of a person are always linked together by causation [Hume] |
| Full Idea: Whatever changes a person endures, his several parts are still connected by the relation of causation. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: However, the opposite ends of the universe are linked together by causation, so that will not suffice for a theory of personal identity. One might try to specify a complex and tight network of causation (like a brain!) instead of just 'connection'. |
| 1388 | Hume gives us an interesting sketchy causal theory of personal identity [Perry on Hume] |
| Full Idea: I believe Hume offers an interesting if sketchy theory of personal identity, a causal theory, disguised as the revolutionary discovery that there is no such thing as personal identity | |
| From: comment on David Hume (Treatise of Human Nature [1739], I.IV.6) by John Perry - Introduction to 'Personal Identity' Intro | |
| A reaction: There is certainly a theory there, even though Hume ceased to believe in it, which is nowadays covered by the idea that personal identity is a 'fiction', an arbitrary idea that reifies the focus and direction of a bundle of mental events. |
| 21297 | A person is simply a bundle of continually fluctuating perceptions [Hume] |
| Full Idea: [People] are nothing but a bundle or collection of different perceptions, which succeed each other with an inconceivable rapidity, and are in a continual flux and movement. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: Nowadays we must say that this misses the huge non-conscious aspect of what a person is. He seems to see all mental events as equal. Isn't the experience of deciding to focus on this sentence more 'central' than awareness of your feet? |
| 1316 | Introspection always discovers perceptions, and never a Self without perceptions [Hume] |
| Full Idea: I never can catch myself at any time without a perception, and never can observe any thing but the perception. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: The first half can hardly be denied, but I think the second half is just false. What you observe is not just a raw neutral sense-datum, floating in nothing, but a sense-datum that is deeply coloured by MY interests, interpretations and values. |
| 1333 | Memory only reveals personal identity, by showing cause and effect [Hume] |
| Full Idea: Memory does not so much produce as discover personal identity, by showing us the relation of cause and effect among our different perceptions. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: This is a rather strained proposal, as the revelation of a network of cause and effect seems to have no implications for personal identity (unless only 'I' could be the cause). |
| 1332 | We use memory to infer personal actions we have since forgotten [Hume] |
| Full Idea: We can extend the chain of causes acquired from memory, and consequently the identity of our persons beyond our memory, and can comprehend times, and circumstances, and actions, which we have entirely forgot. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: If the principle is just that 'I am my consciousness' (including of my past), then why should not my consciousness of other people's pasts by included in my identity. How do I know that images in my consciousness are MY memories? |
| 21305 | Memory not only reveals identity, but creates it, by producing resemblances [Hume] |
| Full Idea: The memory not only discovers the identity [of the mind], but also contributes to its production, by producing the relation of resemblance among the perceptions | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: This is Hume battling to explain personal identity by his principles of association. He discount 'contiguity'. He doesn't explain how memory creates resemblances. Is not resemblance of idea to fact required in order to remember? |
| 21307 | Who thinks that because you have forgotten an incident you are no longer that person? [Hume] |
| Full Idea: Who will affirm, because he has entirely forgot the incidents of past days, that the present self is not the same person with the self of that time? And by that means overturn all the most established notions of personal identity? | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: This is a swipe at one of Locke's most controversial claims (especially when applied to incidents of criminal behaviour). Hume says memory constitutes this identity, but Locke's view says it merely reveals identity. |
| 21306 | Causation unites our perceptions, by producing, destroying and modifying each other [Hume] |
| Full Idea: As to causation, the true idea of the human mind is to consider it as a system of different perceptions, which are linked together by the relation of cause and effect, and mutually produce, destroy, influence and modify each other. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: He suggests that the associations of memory and causation might be sufficient to produce identity of the mind, and he gives the priority to memory. Eventually the good empiricist despairs because you cannot experience the links. |
| 21294 | A continuous lifelong self must be justified by a single sustained impression, which we don't have [Hume] |
| Full Idea: If any impression gives rise to the idea of self, that impression must continue invariably the same, through the whole course of our lives; since self is supposed to exist after that manner. But there is no impression constant and invariable. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: This is a rather dogmatic application of the requirement that all knowledge must be founded in experience. It fails to recognise that knowledge of the thing having the experiences is a rather special case. We must ask for the best explanation. |
| 21295 | When I introspect I can only observe my perceptions, and never a self which has them [Hume] |
| Full Idea: When I enter most intimately into myself I always stumble on some particular perception or other, of heat or cold, love or hatred, pain or pleasure. I never can catch myself at any time without a perception, and never observe any thing but the perception. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: It isn't like looking for your car in the car park. The prior question should be: assuming you do have a persisting self, what would you expect introspection to reveal about it? |
| 21298 | We pretend our perceptions are continuous, and imagine a self to fill the gaps [Hume] |
| Full Idea: We feign the continued existence of the perceptions of our senses, to remove their interruption; and run into the notion of a soul, and self, and substance, to disguise the variation. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: Modern neuroscience (according to Dennett) endorses this, because the brain continually fills in gaps in experience (as it fills in the blindspot during normal vision). |
| 21304 | Identity in the mind is a fiction, like that fiction that plants and animals stay the same [Hume] |
| Full Idea: The identity we ascribe to the mind is only a fictitious one, and of a like kind with that we ascribe to vegetable and animal bodies. It cannot therefore have a different origin, but must proceed from a like operation of the imagination upon like objects. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: Sustained purpose is Hume's common factor. Is the identity over time ascribed to the body of a single animal nothing more than a fiction? It is a wise ascription, compared to stupid ascriptions to gerrymandered objects. |
| 18717 | Thought is an activity which we perform by the expression of it [Wittgenstein] |
| Full Idea: Thought is an activity which we perform by the expression of it, and lasts as long as the expression. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B VIII) | |
| A reaction: I take this to be an outmoded view of thought, which modern cognitive science has undermined, by showing how little of our thinking is actually conscious. |
| 18725 | A proposition draws a line around the facts which agree with it [Wittgenstein] |
| Full Idea: A proposition gives reality a degree of freedom; it draws a line round the facts which agree with it, and distinguishes them from those which do not. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B XIII.2) | |
| A reaction: This seems to be the idea of meaning as the range of truth conditions. Propositions as sets of possible worlds extends this into possible facts which agree with the proposition. Most facts neither agree nor disagree with some proposition. |
| 18728 | The meaning of a proposition is the mode of its verification [Wittgenstein] |
| Full Idea: The meaning of a proposition is the mode of its verification (and two propositions cannot have the same verification). | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], C I) | |
| A reaction: Does this mean that if two sentences have the same mode of verification, then they must be expressing the same proposition? I guess so. |
| 18705 | Words function only in propositions, like levers in a machine [Wittgenstein] |
| Full Idea: Words function only in propositions, like the levers in a machine. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], A I.4) | |
| A reaction: Hm. Consider the word 'tree'. Did you manage to do it? Was it just a noise? |
| 18711 | A proposition is any expression which can be significantly negated [Wittgenstein] |
| Full Idea: Any affirmation can be negated: if it has sense to say p it also has sense to say ¬p. ...A proposition therefore is any expression which can be significantly negated. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], B I.2) | |
| A reaction: I'm not sure about 'therefore'. I'm thinking you would have to already grasp the proposition in order to apply his negation test. |
| 20030 | If one event causes another, the two events must be wholly distinct [Hume, by Wilson/Schpall] |
| Full Idea: Hume's maxim is that if one event cause another, then the two events must be wholly distinct. | |
| From: report of David Hume (Treatise of Human Nature [1739]) by Wilson,G/Schpall,S - Action 3 | |
| A reaction: [Anyone know the original reference?] So we are not allowed to say that one part of an event caused another. The charged caused the victory, so they are two events, but in another context the whole battle is one event. |
| 6692 | For Hume, practical reason has little force, because we can always modify our desires [Hume, by Graham] |
| Full Idea: In Hume's account of action, practical reason is not a very forceful guide to conduct, since we can escape its demands by abandoning or modifying our desires. | |
| From: report of David Hume (Treatise of Human Nature [1739]) by Gordon Graham - Eight Theories of Ethics Ch.6 | |
| A reaction: Presumably a desire can be a good reason, and we can passionately desire to be rational, etc., so this is a rather complex issue. 'Pure reason' is not 'all-or-nothing', and neither is pure desire. |
| 8257 | Reason alone can never be a motive to any action of the will [Hume] |
| Full Idea: Reason alone can never be a motive to any action of the will. | |
| From: David Hume (Treatise of Human Nature [1739], II.III.3) | |
| A reaction: This is Hume's notorious total rejection of Socratic intellectualism, a stilleto in the back of the 'age of reason'. Hume thinks desire is the motivator. He's probably right. Why should truth motivate? See Idea 4421. |
| 22374 | You can only hold people responsible for actions which arise out of their character [Hume] |
| Full Idea: Where actions proceed not from some cause in the characters and dispositions of the person who performed them, they infix not themselves upon him, and can neither redound to his honour if good, nor infamy if evil. The action in itself may be blameable. | |
| From: David Hume (Treatise of Human Nature [1739], II.III.2), quoted by Philippa Foot - Free Will as Involving Determinism p.70 | |
| A reaction: I agree with Foot that this is wrong. Uncharacteristic actions still reflect on the person. The last sentence is wrong too. If you ignore the agent of an action, it can't be distinguished from a flash of lightning. |
| 22382 | We cannot discover vice by studying a wilful murder; that only arises from our own feelings [Hume] |
| Full Idea: Examine wilful murder and see if you can find the matter of fact called vice. You only find certain passions, motives, volitions and thoughts. There is no matter of fact in the case. You can never find it till you turn your reflexion into your own breast. | |
| From: David Hume (Treatise of Human Nature [1739], III.I.2), quoted by Philippa Foot - Hume on Moral Judgement p.77 | |
| A reaction: [...In you breast you find 'disapprobation'] The question Foot asks is whether the facts of the case are relevant to the disapprobation. If they are not, as Hume implies, then it would be rational to feel the same disapprobation about drinking coffee. |
| 4008 | Modern science has destroyed the Platonic synthesis of scientific explanation and morality [Hume, by Taylor,C] |
| Full Idea: From our modern perspective, the Platonic synthesis of scientific explanation and moral insight lies irrecoverably shattered by the rise of natural science. | |
| From: report of David Hume (Treatise of Human Nature [1739]) by Charles Taylor - Sources of the Self §3.2 | |
| A reaction: Modern attempts to challenge Hume's separation of fact from value have failed, but a return to the Greek perspective presents a plausible alternative. |
| 8067 | The problem of getting to 'ought' from 'is' would also apply in getting to 'owes' or 'needs' [Anscombe on Hume] |
| Full Idea: Hume's objection to passing from 'is' to 'ought' would equally apply to passing from 'is' to 'owes' or from 'is' to 'needs'. | |
| From: comment on David Hume (Treatise of Human Nature [1739]) by G.E.M. Anscombe - Modern Moral Philosophy p.176 | |
| A reaction: Profound and important. The empirical and emotivist (nay, nihilist) clinging to the total independence of duties from facts crumbles when looking at facts of human nature or of social groups. Creatures ought to feed; societies ought to flourish. |
| 4578 | You can't move from 'is' to 'ought' without giving some explanation or reason for the deduction [Hume] |
| Full Idea: In many writers I find that instead of the usual propositions 'is' and 'is not', I then find no proposition that is not connected with an 'ought' or an 'ought not'. It is necessary that a reason be given for how one can be a deduction from the other. | |
| From: David Hume (Treatise of Human Nature [1739], III.1.1) | |
| A reaction: A huge claim, the basis of the value-free modern scientific world view. Possible escapes are Greek virtue theory, or Kantian principles, or some sort of a priori values (as in Charles Taylor). |
| 3650 | Total selfishness is not irrational [Hume] |
| Full Idea: It is not contrary to reason to prefer the destruction of the whole world to the scratching of my finger. | |
| From: David Hume (Treatise of Human Nature [1739], II.III.ii) | |
| A reaction: A famous idea, and the embodiment of moral nihilism. I say nothing could ever refute someone who held such a view. No moral theory can force someone to care, if they just don't. |
| 14301 | We have no good concept of solidity or matter, because accounts of them are all circular [Hume] |
| Full Idea: In order to form an idea of solidity, we must conceive two bodies pressing on each other without penetration. ..The ideas of secondary qualities are excluded, and the idea of motion depends on extension. This leaves us no just idea of solidity or matter. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.4), quoted by Stephen Mumford - Dispositions 02.3 | |
| A reaction: [compressed] For me these kind of strict empiricist arguments always recede when you accept the notion of an inference to be best explanation. We have some sort of notion of 'matter', but here the physicist seems to take over. |
| 8382 | For Hume a constant conjunction is both necessary and sufficient for causation [Hume, by Crane] |
| Full Idea: Hume held that constant conjunction between As and Bs is both necessary and sufficient for a causal relation. If As and Bs are conjoined that is sufficient for a causal relation; if A and B are causally related, necessarily they are constantly conjoined. | |
| From: report of David Hume (Treatise of Human Nature [1739]) by Tim Crane - Causation 1.2.2 | |
| A reaction: A helpful connection between Hume and the modern debate about conditions for causation (e.g. Mackie). It sounds as if, to spot the necessary condition, you need to independently see that A and B are causally related, which regularity does not allow. |
| 19274 | Hume seems to presuppose necessary connections between mental events [Kripke on Hume] |
| Full Idea: A well-known objection to Hume's analysis of causation is that he presupposes necessary connections between mental events in the theory. | |
| From: comment on David Hume (Treatise of Human Nature [1739]) by Saul A. Kripke - Wittgenstein on Rules and Private Language n 87 | |
| A reaction: Are these the associations that occur within the mind? I'm not clear about the objection, but record it for interest. |
| 18733 | Laws of nature are an aspect of the phenomena, and are just our mode of description [Wittgenstein] |
| Full Idea: The laws of nature are not outside phenomena. They are part of language and of our way of describing things; you cannot discuss them apart from their physical manifestation. | |
| From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], C V C) | |
| A reaction: I suppose this amounts to a Humean regularity theory - that the descriptions pick out patterns in the manifestations. I like the initial claim that they are not external to phenomena. |
| 2609 | If God's decrees are good, and this is not a mere tautology, then goodness is separate from God's decrees [Russell] |
| Full Idea: Theologians have always taught that God's decrees are good, and that this is not a mere tautology: it follows that goodness is logically independent of God's decrees. | |
| From: Bertrand Russell (Human Society in Ethics and Politics [1954], p.48) |
| 21296 | If all of my perceptions were removed by death, nothing more is needed for total annihilation [Hume] |
| Full Idea: Were all my perceptions removed by death, and I could I neither think nor feel nor see nor love nor hate, after the dissolution of my body, I should be enitrely annihilated, nor do I conceive what is further requisite to make me a perfect non-entity. | |
| From: David Hume (Treatise of Human Nature [1739], I.IV.6) | |
| A reaction: 'A perfect non-entity'. How about that for an eighteenth century rejection of immortality of the soul? In the context, his point is that the has no enduring self, apart from this range of experiences. |