30 ideas
| 16943 | Philosophy is continuous with science, and has no external vantage point [Quine] |
| Full Idea: I see philosophy not as an a priori propaedeutic or groundwork for science, but as continuous with science. I see philosophy and science as in the same boat. …There is no external vantage point, no first philosophy. | |
| From: Willard Quine (Natural Kinds [1969], p.126) | |
| A reaction: Philosophy is generalisation. Science holds the upper hand, because it settles the subject-matter to be generalised. |
| 6950 | You can be rational with undetected or minor inconsistencies [Harman] |
| Full Idea: Rationality doesn't require consistency, because you can be rational despite undetected inconsistencies in beliefs, and it isn't always rational to respond to a discovery of inconsistency by dropping everything in favour of eliminating that inconsistency. | |
| From: Gilbert Harman (Rationality [1995], 1.2) | |
| A reaction: This strikes me as being correct, and is (I am beginning to realise) a vital contribution made to our understanding by pragmatism. European thinking has been too keen on logic as the model of good reasoning. |
| 6954 | A coherent conceptual scheme contains best explanations of most of your beliefs [Harman] |
| Full Idea: A set of unrelated beliefs seems less coherent than a tightly organized conceptual scheme that contains explanatory principles that make sense of most of your beliefs; this is why inference to the best explanation is an attractive pattern of inference. | |
| From: Gilbert Harman (Rationality [1995], 1.5.2) | |
| A reaction: I find this a very appealing proposal. The central aim of rational thought seems to me to be best explanation, and I increasingly think that most of my beliefs rest on their apparent coherence, rather than their foundations. |
| 16949 | Klein summarised geometry as grouped together by transformations [Quine] |
| Full Idea: Felix Klein's so-called 'Erlangerprogramm' in geometry involved characterizing the various branches of geometry by what transformations were irrelevant to each. | |
| From: Willard Quine (Natural Kinds [1969], p.137) |
| 13949 | All models of Peano axioms are isomorphic, so the models all seem equally good for natural numbers [Cartwright,R on Peano] |
| Full Idea: Peano's axioms are categorical (any two models are isomorphic). Some conclude that the concept of natural number is adequately represented by them, but we cannot identify natural numbers with one rather than another of the isomorphic models. | |
| From: comment on Giuseppe Peano (Principles of Arithmetic, by a new method [1889], 11) by Richard Cartwright - Propositions 11 | |
| A reaction: This is a striking anticipation of Benacerraf's famous point about different set theory accounts of numbers, where all models seem to work equally well. Cartwright is saying that others have pointed this out. |
| 18113 | PA concerns any entities which satisfy the axioms [Peano, by Bostock] |
| Full Idea: Peano Arithmetic is about any system of entities that satisfies the Peano axioms. | |
| From: report of Giuseppe Peano (Principles of Arithmetic, by a new method [1889], 6.3) by David Bostock - Philosophy of Mathematics 6.3 | |
| A reaction: This doesn't sound like numbers in the fullest sense, since those should facilitate counting objects. '3' should mean that number of rose petals, and not just a position in a well-ordered series. |
| 17634 | Peano axioms not only support arithmetic, but are also fairly obvious [Peano, by Russell] |
| Full Idea: Peano's premises are recommended not only by the fact that arithmetic follows from them, but also by their inherent obviousness. | |
| From: report of Giuseppe Peano (Principles of Arithmetic, by a new method [1889], p.276) by Bertrand Russell - Regressive Method for Premises in Mathematics p.276 |
| 15653 | We can add Reflexion Principles to Peano Arithmetic, which assert its consistency or soundness [Halbach on Peano] |
| Full Idea: Peano Arithmetic cannot derive its own consistency from within itself. But it can be strengthened by adding this consistency statement or by stronger axioms (particularly ones partially expressing soundness). These are known as Reflexion Principles. | |
| From: comment on Giuseppe Peano (Principles of Arithmetic, by a new method [1889], 1.2) by Volker Halbach - Axiomatic Theories of Truth (2005 ver) 1.2 |
| 17635 | Arithmetic can have even simpler logical premises than the Peano Axioms [Russell on Peano] |
| Full Idea: Peano's premises are not the ultimate logical premises of arithmetic. Simpler premises and simpler primitive ideas are to be had by carrying our analysis on into symbolic logic. | |
| From: comment on Giuseppe Peano (Principles of Arithmetic, by a new method [1889], p.276) by Bertrand Russell - Regressive Method for Premises in Mathematics p.276 |
| 16939 | Mass terms just concern spread, but other terms involve both spread and individuation [Quine] |
| Full Idea: 'Yellow' and 'water' are mass terms, concerned only with spread; 'apple' and 'square' are terms of divided reference, concerned with both spread and individuation. | |
| From: Willard Quine (Natural Kinds [1969], p.124) | |
| A reaction: Would you like some apple? Pass me that water. It is helpful to see that it is a requirement of 'individuation' that is missing from terms for stuff. |
| 16948 | Once we know the mechanism of a disposition, we can eliminate 'similarity' [Quine] |
| Full Idea: Once we can legitimize a disposition term by defining the relevant similarity standard, we are apt to know the mechanism of the disposition, and so by-pass the similarity. | |
| From: Willard Quine (Natural Kinds [1969], p.135) | |
| A reaction: I love mechanisms, but can we characterise mechanisms without mentioning powers and dispositions? Quine's dream is to eliminate 'similarity'. |
| 16945 | We judge things to be soluble if they are the same kind as, or similar to, things that do dissolve [Quine] |
| Full Idea: Intuitively, what qualifies a thing as soluble though it never gets into water is that it is of the same kind as the things that actually did or will dissolve; it is similar to them. | |
| From: Willard Quine (Natural Kinds [1969], p.130) | |
| A reaction: If you can judge that the similar things 'will' dissolve, you can cut to the chase and judge that this thing will dissolve. |
| 16944 | Science is common sense, with a sophisticated method [Quine] |
| Full Idea: Sciences differ from common sense only in the degree of methodological sophistication. | |
| From: Willard Quine (Natural Kinds [1969], p.129) | |
| A reaction: Science is normal thinking about the world, but it is teamwork, with the bar set very high. |
| 6955 | Enumerative induction is inference to the best explanation [Harman] |
| Full Idea: We might think of enumerative induction as inference to the best explanation, taking the generalization to explain its instances. | |
| From: Gilbert Harman (Rationality [1995], 1.5.2) | |
| A reaction: This is a helpful connection. The best explanation of these swans being white is that all swans are white; it ceased to be the best explanation when black swans turned up. In the ultimate case, a law of nature is the explanation. |
| 16941 | Induction relies on similar effects following from each cause [Quine] |
| Full Idea: Induction expresses our hopes that similar causes will have similar effects. | |
| From: Willard Quine (Natural Kinds [1969], p.125) | |
| A reaction: Some top philosophers are also top teachers, and Quine was one of them, in his writings. He boils it down for the layman. Once again, he is pointing to the fundamental role of the similarity relation. |
| 16940 | Induction is just more of the same: animal expectations [Quine] |
| Full Idea: Induction is essentially only more of the same: animal expectation or habit formation. | |
| From: Willard Quine (Natural Kinds [1969], p.125) | |
| A reaction: My working definition of induction is 'learning from experience', but that doesn't disagree with Quine. Lipton has a richer account of different types of induction. Quine's point is that it rests on resemblance. |
| 6952 | Induction is 'defeasible', since additional information can invalidate it [Harman] |
| Full Idea: It is sometimes said that inductive reasoning is 'defeasible', meaning that considerations that support a given conclusion can be defeated by additional information. | |
| From: Gilbert Harman (Rationality [1995], 1.4.5) | |
| A reaction: True. The point is that being defeasible does not prevent such thinking from being rational. The rational part of it is to acknowledge that your conclusion is defeasible. |
| 6953 | All reasoning is inductive, and deduction only concerns implication [Harman] |
| Full Idea: Deductive logic is concerned with deductive implication, not deductive reasoning; all reasoning is inductive | |
| From: Gilbert Harman (Rationality [1995], 1.4.5) | |
| A reaction: This may be an attempt to stipulate how the word 'reasoning' should be used in future. It is, though, a bold and interesting claim, given the reputation of induction (since Hume) of being a totally irrational process. |
| 16933 | Grue is a puzzle because the notions of similarity and kind are dubious in science [Quine] |
| Full Idea: What makes Goodman's example a puzzle is the dubious scientific standing of a general notion of similarity, or of kind. | |
| From: Willard Quine (Natural Kinds [1969], p.116) | |
| A reaction: Illuminating. It might be best expressed as revealing a problem with sortal terms, as employed by Geach, or by Wiggins. Grue is a bit silly, but sortals are subject to convention and culture. 'Natural' properties seem needed. |
| 16934 | General terms depend on similarities among things [Quine] |
| Full Idea: The usual general term, whether a common noun or a verb or an adjective, owes its generality to some resemblance among the things referred to. | |
| From: Willard Quine (Natural Kinds [1969], p.116) | |
| A reaction: Quine has a nice analysis of the basic role of similarity in a huge amount of supposedly strict scientific thought. |
| 16938 | To learn yellow by observation, must we be told to look at the colour? [Quine] |
| Full Idea: According to the 'respects' view, our learning of yellow by ostension would have depended on our first having been told or somehow apprised that it was going to be a question of color. | |
| From: Willard Quine (Natural Kinds [1969], p.122) | |
| A reaction: Quine suggests there is just one notion of similarity, and respects can be 'abstracted' afterwards. Even the ontologically ruthless Quine admits psychological abstraction! |
| 8486 | Standards of similarity are innate, and the spacing of qualities such as colours can be mapped [Quine] |
| Full Idea: A standard of similarity is in some sense innate. The spacing of qualities (such as red, pink and blue) can be explored and mapped in the laboratory by experiments. They are needed for all learning. | |
| From: Willard Quine (Natural Kinds [1969], p.123) | |
| A reaction: This reasserts Hume's original point in more scientific terms. It is one of the undeniable facts about our perceptions of qualities and properties, no matter how platonist your view of universals may be. |
| 16947 | Similarity is just interchangeability in the cosmic machine [Quine] |
| Full Idea: Things are similar to the extent that they are interchangeable parts of the cosmic machine. | |
| From: Willard Quine (Natural Kinds [1969], p.134) | |
| A reaction: This is a major idea for Quine, because it is a means to gradually eliminate the fuzzy ideas of 'resemblance' or 'similarity' or 'natural kind' from science. I love it! Two tigers are same insofar as they are substitutable. |
| 6951 | Ordinary rationality is conservative, starting from where your beliefs currently are [Harman] |
| Full Idea: Ordinary rationality is generally conservative, in the sense that you start from where you are, with your present beliefs and intentions. | |
| From: Gilbert Harman (Rationality [1995], 1.3) | |
| A reaction: This stands opposed to the Cartesian or philosophers' rationality, which requires that (where possible) everything be proved from scratch. Harman seems right, that the normal onus of proof is on changing beliefs, rather proving you should retain them. |
| 16932 | Projectible predicates can be universalised about the kind to which they refer [Quine] |
| Full Idea: 'Projectible' predicates are predicates F and G whose shared instances all do count, for whatever reason, towards confirmation of 'All F are G'. ….A projectible predicate is one that is true of all and only the things of a kind. | |
| From: Willard Quine (Natural Kinds [1969], p.115-6) | |
| A reaction: Both Quine and Goodman are infuriatingly brief about the introduction of this concept. 'Red' is true of all ripe tomatoes, but not 'only' of them. Hardly any predicates are true only of one kind. Is that a scholastic 'proprium'? |
| 7375 | Quine probably regrets natural kinds now being treated as essences [Quine, by Dennett] |
| Full Idea: The concept of natural kinds was reintroduced by Quine, who may now regret the way it has become a stand-in for the dubious but covertly popular concept of essences. | |
| From: report of Willard Quine (Natural Kinds [1969]) by Daniel C. Dennett - Consciousness Explained 12.2 n2 | |
| A reaction: He is right that Quine would regret it, and he is right that we can't assume that there are necessary essences just because there seem to be stable natural kinds, but personally I am an essentialist, so I'm not that bothered. |
| 16935 | If similarity has no degrees, kinds cannot be contained within one another [Quine] |
| Full Idea: If similarity has no degrees there is no containing of kinds within broader kinds. If colored things are a kind, they are similar, but red things are too narrow for a kind. If red things are a kind, colored things are not similar, and it's too broad. | |
| From: Willard Quine (Natural Kinds [1969], p.118) | |
| A reaction: [compressed] I'm on Quine's side with this. We glibly talk of 'kinds', but the criteria for sorting things into kinds seems to be a mess. Quine goes on to offer a better account than the (diadic, yes-no) one rejected here. |
| 16936 | Comparative similarity allows the kind 'colored' to contain the kind 'red' [Quine] |
| Full Idea: With the triadic relation of comparative similarity, kinds can contain one another, as well as overlapping. Red and colored things can both count as kinds. Colored things all resemble one another, even though less than red things do. | |
| From: Willard Quine (Natural Kinds [1969], p.119) | |
| A reaction: [compressed] Quine claims that comparative similarity is necessary for kinds - that there be some 'foil' in a similarity - that A is more like C than B is. |
| 16937 | You can't base kinds just on resemblance, because chains of resemblance are a muddle [Quine] |
| Full Idea: If kinds are based on similarity, this has the Imperfect Community problem. Red round, red wooden and round wooden things all resemble one another somehow. There may be nothing outside the set resembling them, so it meets the definition of kind. | |
| From: Willard Quine (Natural Kinds [1969], p.120) | |
| A reaction: [ref. to Goodman 'Structure' 2nd 163- , which attacks Carnap on this] This suggests an invocation of Wittgenstein's family resemblance, which won't be much help for natural kinds. |
| 16942 | It is hard to see how regularities could be explained [Quine] |
| Full Idea: Why there have been regularities is an obscure question, for it is hard to see what would count as an answer. | |
| From: Willard Quine (Natural Kinds [1969], p.126) | |
| A reaction: This is the standard pessimism of the 20th century Humeans, but it strikes me as comparable to the pessimism about science found in Locke and Hume. Regularities are explained all the time by scientists, though the lowest level may be hopeless. |