23 ideas
| 18543 | Do aesthetic reasons count as reasons, if they are rejectable without contradiction? [Scruton] |
| Full Idea: The judgement of beauty makes a claim about its object, and can be supported by reasons. But the reasons do not compel the judgement and can be rejected without contradiction. So are they reasons or aren't they? | |
| From: Roger Scruton (Beauty: a very short introduction [2011], 1) | |
| A reaction: I suspect that what he is really referring to is evidence rather than reasons. |
| 13838 | A decent modern definition should always imply a semantics [Hacking] |
| Full Idea: Today we expect that anything worth calling a definition should imply a semantics. | |
| From: Ian Hacking (What is Logic? [1979], §10) | |
| A reaction: He compares this with Gentzen 1935, who was attempting purely syntactic definitions of the logical connectives. |
| 18542 | Defining truth presupposes that there can be a true definition [Scruton] |
| Full Idea: How can you define truth, without already assuming the distinction between a true definition and a false one? | |
| From: Roger Scruton (Beauty: a very short introduction [2011], 1) | |
| A reaction: Don't say we have to accept truth as yet another primitive! Philosophers are out of business if all the basic concepts are primitive. The axiomatic approach to truth is an alternative - by specifying how the primitive should be used. |
| 13833 | 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking] |
| Full Idea: 'Dilution' (or 'Thinning') provides an essential contrast between deductive and inductive reasoning; for the introduction of new premises may spoil an inductive inference. | |
| From: Ian Hacking (What is Logic? [1979], §06.2) | |
| A reaction: That is, inductive logic (if there is such a thing) is clearly non-monotonic, whereas classical inductive logic is monotonic. |
| 13834 | Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking] |
| Full Idea: If A |- B and B |- C, then A |- C. This generalises to: If Γ|-A,Θ and Γ,A |- Θ, then Γ |- Θ. Gentzen called this 'cut'. It is the transitivity of a deduction. | |
| From: Ian Hacking (What is Logic? [1979], §06.3) | |
| A reaction: I read the generalisation as 'If A can be either a premise or a conclusion, you can bypass it'. The first version is just transitivity (which by-passes the middle step). |
| 13835 | Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking] |
| Full Idea: Only the cut rule can have a conclusion that is less complex than its premises. Hence when cut is not used, a derivation is quite literally constructive, building up from components. Any theorem obtained by cut can be obtained without it. | |
| From: Ian Hacking (What is Logic? [1979], §08) |
| 13845 | The various logics are abstractions made from terms like 'if...then' in English [Hacking] |
| Full Idea: I don't believe English is by nature classical or intuitionistic etc. These are abstractions made by logicians. Logicians attend to numerous different objects that might be served by 'If...then', like material conditional, strict or relevant implication. | |
| From: Ian Hacking (What is Logic? [1979], §15) | |
| A reaction: The idea that they are 'abstractions' is close to my heart. Abstractions from what? Surely 'if...then' has a standard character when employed in normal conversation? |
| 13840 | First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking] |
| Full Idea: First-order logic is the strongest complete compact theory with a Löwenheim-Skolem theorem. | |
| From: Ian Hacking (What is Logic? [1979], §13) |
| 13844 | A limitation of first-order logic is that it cannot handle branching quantifiers [Hacking] |
| Full Idea: Henkin proved that there is no first-order treatment of branching quantifiers, which do not seem to involve any idea that is fundamentally different from ordinary quantification. | |
| From: Ian Hacking (What is Logic? [1979], §13) | |
| A reaction: See Hacking for an example of branching quantifiers. Hacking is impressed by this as a real limitation of the first-order logic which he generally favours. |
| 13842 | Second-order completeness seems to need intensional entities and possible worlds [Hacking] |
| Full Idea: Second-order logic has no chance of a completeness theorem unless one ventures into intensional entities and possible worlds. | |
| From: Ian Hacking (What is Logic? [1979], §13) |
| 13837 | With a pure notion of truth and consequence, the meanings of connectives are fixed syntactically [Hacking] |
| Full Idea: My doctrine is that the peculiarity of the logical constants resides precisely in that given a certain pure notion of truth and consequence, all the desirable semantic properties of the constants are determined by their syntactic properties. | |
| From: Ian Hacking (What is Logic? [1979], §09) | |
| A reaction: He opposes this to Peacocke 1976, who claims that the logical connectives are essentially semantic in character, concerned with the preservation of truth. |
| 13839 | Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking] |
| Full Idea: For some purposes the variables of first-order logic can be regarded as prepositions and place-holders that could in principle be dispensed with, say by a system of arrows indicating what places fall in the scope of which quantifier. | |
| From: Ian Hacking (What is Logic? [1979], §11) | |
| A reaction: I tend to think of variables as either pronouns, or as definite descriptions, or as temporary names, but not as prepositions. Must address this new idea... |
| 13843 | If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking] |
| Full Idea: A Löwenheim-Skolem theorem holds for anything which, on my delineation, is a logic. | |
| From: Ian Hacking (What is Logic? [1979], §13) | |
| A reaction: I take this to be an unusually conservative view. Shapiro is the chap who can give you an alternative view of these things, or Boolos. |
| 7006 | Observing irrelevant items supports both 'all x are y' and 'all x are non-y', revealing its absurdity [Schofield,J] |
| Full Idea: Although Hempel's raven paradox produces an absurdity of irrelevant observations, we can ignore it because (unlike good observations) observing a white handbag supports the contradictions of 'ravens are black' and 'ravens are non-black'. | |
| From: Jonathan Schofield (talk [2005]), quoted by PG - Db (ideas) | |
| A reaction: The idea of 'eliminating it from our enquiries' cannot be totally irrational (e.g. in detective work), but it is only seriously sensible in a restricted domain (such as a country house) |
| 18546 | The pleasure taken in beauty also aims at understanding and valuing [Scruton] |
| Full Idea: Like the pleasure in friendship, the pleasure in beauty is curious: it aims to understand its object, and to value what it finds. | |
| From: Roger Scruton (Beauty: a very short introduction [2011], 1) | |
| A reaction: At least he is trying to pin down the way in which aesthetic pleasure is phenomenologically different from other kinds of pleasure. |
| 18550 | Art gives us imaginary worlds which we can view impartially [Scruton] |
| Full Idea: One aim of art is to present imaginary worlds, towards which we can adopt, as part of the integral aesthetic attitude, a posture of impartial concern. | |
| From: Roger Scruton (Beauty: a very short introduction [2011], 5) | |
| A reaction: It connects to the pleasure of watching people when they don't know they are being watched (such as watching the street from a restaurant window). Scruton's suggestion makes art resemble examples in philosophy. Cf the Frege-Geach problem in ethics. |
| 18544 | Maybe 'beauty' is too loaded, and we should talk of fittingness or harmony [Scruton] |
| Full Idea: Maybe we can understand the 'beauty' of a building better if we describe it in another and less loaded way, as a form of fittingness or harmony. | |
| From: Roger Scruton (Beauty: a very short introduction [2011], 1) | |
| A reaction: Almost everyone accepts the word 'beauty' for some things, such as a beautiful face, or goal, or steak. I remember a female interviewer writing that, reluctantly, the only appropriate word she could find for Nureyev's face was 'beautiful'. |
| 18553 | Beauty shows us what we should want in order to achieve human fulfilment [Scruton] |
| Full Idea: Beauty speaks to us of human fulfilment: not of things that we want, but of things that we ought to want, because human nature requires them. Such, at least, is my belief. | |
| From: Roger Scruton (Beauty: a very short introduction [2011], 7) | |
| A reaction: I'm not sure how this works with a beautiful natural landscape. And what should I see that I ought to desire after viewing a great Rembrandt self-portrait? That I don't want to end up looking as bleak as that? Hm. Lofty words. |
| 18556 | Beauty is rationally founded, inviting meaning, comparison and self-reflection [Scruton] |
| Full Idea: Beauty is rationally founded; it challenges us to find meaning in its object, to make critical comparisons, and to examine our own lives and emotions in the light of what we find. | |
| From: Roger Scruton (Beauty: a very short introduction [2011], 9) | |
| A reaction: This is the Kantian tradition, and I'm not finding it very persuasive. It seems to place the value of beauty in what we do with it afterwards, and he seems to make beauty a necessary stepping stone to virtue. I see beauty as more sui generis. |
| 18548 | Natural beauty reassures us that the world is where we belong [Scruton] |
| Full Idea: The experience of natural beauty is not a sense of 'how nice!' or 'how pleasant!' It contains a reassurance that this world is a right and fitting place to be - a home in which our human powers and prospects find confirmation. | |
| From: Roger Scruton (Beauty: a very short introduction [2011], 2) | |
| A reaction: To call it a 'reassurance' and 'confirmation' sounds like theism, anthropomorphism, or the pathetic fallacy. That said, this is certainly a heart-warming idea, and hence must contain a grain of truth. |
| 18551 | Croce says art makes inarticulate intuitions conscious; rival views say the audience is the main concern [Scruton] |
| Full Idea: The Croce model is of an inarticulate inner state (an 'intuition') becoming articulate and conscious through artistic expression. The rival model is fitting thing together so as to create links which resonate in the audience's feelings. | |
| From: Roger Scruton (Beauty: a very short introduction [2011], 5) | |
| A reaction: The first model tells you nothing about how the artist imagines the audience reacting. The second model tells you nothing about what matters personally to the artist. A good theory must do both! |
| 18541 | Beauty (unlike truth and goodness) is questionable as an ultimate value [Scruton] |
| Full Idea: The status of beauty as an ultimate value is questionable, in the way that the status of truth and goodness are not. | |
| From: Roger Scruton (Beauty: a very short introduction [2011], 1) | |
| A reaction: We suspect that a love of beauty may be a bit parochial, where it is hard to conceive of living creatures anywhere in the cosmos who don't value the other two. |
| 18554 | Prostitution is wrong because it hardens the soul, since soul and body are one [Scruton] |
| Full Idea: The condemnation of prostitution was not just puritan bigotry; it was a recognition of a profound truth, that you and your body are not two things but one, and by selling the body you harden your soul. | |
| From: Roger Scruton (Beauty: a very short introduction [2011], 7) | |
| A reaction: No one, I imagine, who condones or even enthuses about prostitution would hope that their own daughter followed the profession, so there is something wrong with it. But must an enthusiastic and cheerful prostitute necessarily have a hard soul? |