17 ideas
| 17596 | Coherence problems have positive and negative restraints; solutions maximise constraint satisfaction [Thagard] |
| Full Idea: A coherence problem is a set of elements connected by positive and negative restraints, and a solution consists of partitioning the elements into two sets (accepted and rejected) in a way that maximises satisfaction of the constraints. | |
| From: Paul Thagard (Coherence: The Price is Right [2012], p.42) | |
| A reaction: I'm enthusiastic about this, as it begins to clarify the central activity of epistemology, which is the quest for best explanations. |
| 17597 | Coherence is explanatory, deductive, conceptual, analogical, perceptual, and deliberative [Thagard] |
| Full Idea: I propose that there are six main kinds of coherence: explanatory, deductive, conceptual, analogical, perceptual, and deliberative. ...Epistemic coherence is a combination of the first five kinds, and ethics adds the sixth. | |
| From: Paul Thagard (Coherence: The Price is Right [2012], p.43) | |
| A reaction: Wonderful. Someone is getting to grips with the concept of coherence, instead of just whingeing about how vague it is. |
| 17598 | Explanatory coherence needs symmetry,explanation,analogy,data priority, contradiction,competition,acceptance [Thagard] |
| Full Idea: Informally, a theory of explanatory coherence has the principles of symmetry, explanation, analogy, data priority, contradiction, competition and acceptance. | |
| From: Paul Thagard (Coherence: The Price is Right [2012], p.44) | |
| A reaction: [Thagard give a concise summary of his theory here] Again Thagard makes a wonderful contribution in an area where most thinkers are pessimistic about making any progress. His principles are very plausible. |
| 17602 | Verisimilitude comes from including more phenomena, and revealing what underlies [Thagard] |
| Full Idea: A scientific theory is progressively approximating the truth if it increases its explanatory coherence by broadening to more phenomena and deepening by investigating layers of mechanisms. | |
| From: Paul Thagard (Coherence: The Price is Right [2012], p.46) |
| 10928 | Maybe we can quantify modally if the objects are intensional, but it seems unlikely [Quine] |
| Full Idea: Perhaps there is no objection to quantifying into modal contexts as long as the values of any variables thus quantified are limited to intensional objects, but they also lead to disturbing examples. | |
| From: Willard Quine (Reference and Modality [1953], §3) | |
| A reaction: [Quine goes on to give his examples] I take it that possibilities are features of actual reality, not merely objects of thought. The problem is that they are harder to know than actual objects. |
| 10925 | Failure of substitutivity shows that a personal name is not purely referential [Quine] |
| Full Idea: Failure of substitutivity shows that the occurrence of a personal name is not purely referential. | |
| From: Willard Quine (Reference and Modality [1953], §1) | |
| A reaction: I don't think I understand the notion of a name being 'purely' referential, as if it somehow ceased to be a word, and was completely transparent to the named object. |
| 10926 | Quantifying into referentially opaque contexts often produces nonsense [Quine] |
| Full Idea: If to a referentially opaque context of a variable we apply a quantifier, with the intention that it govern that variable from outside the referentially opaque context, then what we commonly end up with is unintended sense or nonsense. | |
| From: Willard Quine (Reference and Modality [1953], §2) |
| 10930 | Quantification into modal contexts requires objects to have an essence [Quine] |
| Full Idea: A reversion to Aristotelian essentialism is required if quantification into modal contexts is to be insisted on. An object must be seen as having some of its traits necessarily. | |
| From: Willard Quine (Reference and Modality [1953], §3) | |
| A reaction: This thought leads directly to Kripke's proposal of rigid designation of objects (and Lewis response of counterparts), which really gets modal logic off the ground. Quine's challenge remains - the modal logic entails a huge metaphysical commitment. |
| 14645 | To be necessarily greater than 7 is not a trait of 7, but depends on how 7 is referred to [Quine] |
| Full Idea: To be necessarily greater than 7 is not a trait of a number, but depends on the manner of referring to the number. | |
| From: Willard Quine (Reference and Modality [1953], §2) | |
| A reaction: The most concise quotation of Quine's objection to 'de re' modality. The point is whether the number might have been referred to as 'the number of planets'. So many of these problems are solved by fixing unambiguous propositions first. |
| 9201 | Whether 9 is necessarily greater than 7 depends on how '9' is described [Quine, by Fine,K] |
| Full Idea: Quine's metaphysical argument is that if 9 is 7+2 the number 9 will be necessarily greater than 7, but when 9 is described as the number of planets, the number will not be necessarily greater than 7. The necessity depends on how it is described. | |
| From: report of Willard Quine (Reference and Modality [1953]) by Kit Fine - Intro to 'Modality and Tense' p. 3 | |
| A reaction: Thus necessity would be entirely 'de dicto' and not 'de re'. It sounds like a feeble argument. If I describe the law of identity (a=a) as 'my least favourite logical principle', that won't make it contingent. Describe 9, or refer to it? See Idea 9203. |
| 10927 | Necessity only applies to objects if they are distinctively specified [Quine] |
| Full Idea: Necessity does not properly apply to the fulfilment of conditions by objects (such as the number which numbers the planets), apart from special ways of specifying them. | |
| From: Willard Quine (Reference and Modality [1953], §3) | |
| A reaction: This appears to say that the only necessity is 'de dicto', and that there is no such thing as 'de re' necessity (of the thing in itself). How can Quine deny that there might be de re necessities? His point is epistemological - how can we know them? |
| 9203 | We can't quantify in modal contexts, because the modality depends on descriptions, not objects [Quine, by Fine,K] |
| Full Idea: 'Necessarily 9>7' may be true while the sentence 'necessarily the number of planets < 7' is false, even though it is obtained by substituting a coreferential term. So quantification in these contexts is unintelligible, without a clear object. | |
| From: report of Willard Quine (Reference and Modality [1953]) by Kit Fine - Intro to 'Modality and Tense' p. 4 | |
| A reaction: This is Quine's second argument against modality. See Idea 9201 for his first. Fine attempts to refute it. The standard reply seems to be to insist that 9 must therefore be an object, which pushes materialist philosophers into reluctant platonism. |
| 17601 | Neither a priori rationalism nor sense data empiricism account for scientific knowledge [Thagard] |
| Full Idea: Both rationalists (who start with a priori truths and make deductions) and empiricists (starting with indubitable sense data and what follows) would guarantee truth, but neither even begins to account for scientific knowledge. | |
| From: Paul Thagard (Coherence: The Price is Right [2012], p.46) | |
| A reaction: Thagard's answer, and mine, is inference to the best explanation, but goes beyond both the a priori truths and the perceptions. |
| 17600 | Bayesian inference is forced to rely on approximations [Thagard] |
| Full Idea: It is well known that the general problem with Bayesian inference is that it is computationally intractable, so the algorithms used for computing posterior probabilities have to be approximations. | |
| From: Paul Thagard (Coherence: The Price is Right [2012], p.45) | |
| A reaction: Thagard makes this sound devastating, but then concedes that all theories have to rely on approximations, so I haven't quite grasped this idea. He gives references. |
| 17599 | The best theory has the highest subjective (Bayesian) probability? [Thagard] |
| Full Idea: On the Bayesian view, the best theory is the one with the highest subjective probability, given the evidence as calculated by Bayes's theorem. | |
| From: Paul Thagard (Coherence: The Price is Right [2012], p.45) |
| 17722 | The concept 'red' is tied to what actually individuates red things [Peacocke] |
| Full Idea: The possession conditions for the concept 'red' of the colour red are tied to those very conditions which individuate the colour red. | |
| From: Christopher Peacocke (Explaining the A Priori [2000], p.267), quoted by Carrie Jenkins - Grounding Concepts 2.5 | |
| A reaction: Jenkins reports that he therefore argues that we can learn something about the word 'red' from thinking about the concept 'red', which is his new theory of the a priori. I find 'possession conditions' and 'individuation' to be very woolly concepts. |
| 10931 | We can't say 'necessarily if x is in water then x dissolves' if we can't quantify modally [Quine] |
| Full Idea: To say an object is soluble in water is to say that it would dissolve if it were in water,..which implies that 'necessarily if x is in water then x dissolves'. Yet we do not know if there is a suitable sense of 'necessarily' into which we can so quantify. | |
| From: Willard Quine (Reference and Modality [1953], §4) | |
| A reaction: This is why there has been a huge revival of scientific essentialism - because Krike seems to offer exacty the account which Quine said was missing. So can you have modal logic without rigid designation? |