35 ideas
| 21360 | Unobservant thinkers tend to dogmatise using insufficient facts [Aristotle] |
| Full Idea: Those whom devotion to abstract discussions has rendered unobservant of the facts are too ready to dogmatise on the basis of a few observations. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 316a09) | |
| A reaction: I totally approve of the idea that a good philosopher should be 'observant'. Prestige in modern analytic philosophy comes from logical ability. There should be some rival criterion for attentiveness to facts, with equal prestige. |
| 13010 | In order to select the logic justified by experience, we would need to use a lot of logic [Boghossian on Quine] |
| Full Idea: Quine ends up with the logic that is maximally justified by experience, ...but a large number of the core principles of logic will have to be used to select the logic that is maximally justified by experience. | |
| From: comment on Willard Quine (Carnap and Logical Truth [1954]) by Paul Boghossian - Knowledge of Logic p.233 | |
| A reaction: In order to grasp some core principles of logic, you will probably need a certain amount of experience. I take logic to be an abstracted feature of reality (unless it is extended by pure fictions). Some basic logic may be hard wired in us. |
| 9002 | Elementary logic requires truth-functions, quantifiers (and variables), identity, and also sets of variables [Quine] |
| Full Idea: Elementary logic, as commonly systematized nowadays, comprises truth-function theory (involving 'or', 'and', 'not' etc.), quantifiers (and their variables), and identity theory ('='). In addition, set theory requires classes among values of variables. | |
| From: Willard Quine (Carnap and Logical Truth [1954], II) | |
| A reaction: Quine is famous for trying to squeeze properties out of the picture, which would then block higher-order logics (which quantify over properties). Quine's list gives a nice programme for a student of the philosophy of logic to understand. |
| 13681 | Logical consequence is marked by being preserved under all nonlogical substitutions [Quine, by Sider] |
| Full Idea: Quine's view of logical consequence is that it is when there is no way of uniformly substituting nonlogical expressions in the premises and consequences so that the premises all remain true but the consequence now becomes false. | |
| From: report of Willard Quine (Carnap and Logical Truth [1954], p.103) by Theodore Sider - Logic for Philosophy 1.5 | |
| A reaction: One might just say that the consequence holds if you insert consistent variables for the nonlogical terms, which looks like Aristotle's view of the matter. |
| 13829 | If logical truths essentially depend on logical constants, we had better define the latter [Hacking on Quine] |
| Full Idea: Quine said a logical truth is a truth in which only logical constants occur essentially, ...but then a fruitful definition of 'logical constant' is called for. | |
| From: comment on Willard Quine (Carnap and Logical Truth [1954]) by Ian Hacking - What is Logic? §02 |
| 9003 | Set theory was struggling with higher infinities, when new paradoxes made it baffling [Quine] |
| Full Idea: Unlike elementary logic, the truths of set theory are not obvious. Set theory was straining at the leash of intuition ever since Cantor discovered higher infinites; and with the added impetus of the paradoxes of set theory the leash snapped. | |
| From: Willard Quine (Carnap and Logical Truth [1954], II) | |
| A reaction: This problem seems to have forced Quine into platonism about sets, because he felt they were essential for mathematics and science, but couldn't be constructed with precision. So they must be real, but we don't quite understand them. |
| 13212 | Infinity is only potential, never actual [Aristotle] |
| Full Idea: Nothing is actually infinite. A thing is infinite only potentially. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 318a21) | |
| A reaction: Aristotle is the famous spokesman for this view, though it reappeared somewhat in early twentieth century discussions (e.g. Hilbert). I sympathise with this unfashionable view. Multiple infinites are good fun, but no one knows what they really are. |
| 9004 | If set theory is not actually a branch of logic, then Frege's derivation of arithmetic would not be from logic [Quine] |
| Full Idea: We might say that set theory is not really logic, but a branch of mathematics. This would deprive 'includes' of the status of a logical word. Frege's derivation of arithmetic would then cease to count as a derivation from logic: for he used set theory. | |
| From: Willard Quine (Carnap and Logical Truth [1954], II) | |
| A reaction: Quine has been making the point that higher infinities and the paradoxes undermine the status of set theory as logic, but he decides to continue thinking of set theory as logic. Critics of logicism frequently ask whether the reduction is to logic. |
| 13221 | Existence is either potential or actual [Aristotle] |
| Full Idea: Some things are-potentially while others are-actually. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 327b24) | |
| A reaction: I've read a lot of Aristotle, but am still not quite clear what this distinction means. I like the distinction between a thing's actual being and its 'modal profile', but the latter may extend well beyond what Aristotle means by potential being. |
| 16100 | True change is in a thing's logos or its matter, not in its qualities [Aristotle] |
| Full Idea: In that which underlies a change there is a factor corresponding to the definition [logon] and there is a material factor. When a change is in these constitutive factors there is coming to be or passing away, but in a thing's qualities it is alteration. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 317a24) | |
| A reaction: This seems to be a key summary of Aristotle's account of change, in the context of his hylomorphism (form-plus-matter). The logos is the account of the thing, which seems to be the definition, which seems to give the form (principle or structure). |
| 16101 | A change in qualities is mere alteration, not true change [Aristotle] |
| Full Idea: When a change occurs in the qualities [pathesi] and is accidental [sumbebekos], there is alteration (rather than true change). | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 317a27) | |
| A reaction: [tr. partly Gill] Aristotle doesn't seem to have a notion of 'properties' in quite our sense. 'Pathe' seems to mean experienced qualities, rather than genuine causal powers. Gill says 'pathe' are always accidental. |
| 12133 | If the substratum persists, it is 'alteration'; if it doesn't, it is 'coming-to-be' or 'passing-away' [Aristotle] |
| Full Idea: Since we must distinguish the substratum and the property whose nature is to be predicated of the substratum,..there is alteration when the substratum persists...but when nothing perceptible persists as a substratum, this is coming-to-be and passing-away. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 319b08-16) | |
| A reaction: As usual, Aristotle clarifies the basis of the problem, by distinguishing two different types of change. Notice the empirical character of his approach, resting on whether or not the substratum is 'perceptible'. |
| 13213 | All comings-to-be are passings-away, and vice versa [Aristotle] |
| Full Idea: Every coming-to-be is a passing away of something else and every passing-away some other thing's coming-to-be. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 319a07) | |
| A reaction: This seems to be the closest that Aristotle gets to sympathy with the Heraclitus view that all is flux. When a sparrow dies and disappears, I am not at all clear what comes to be, except some ex-sparrow material. |
| 9006 | Commitment to universals is as arbitrary or pragmatic as the adoption of a new system of bookkeeping [Quine] |
| Full Idea: One's hypothesis as to there being universals is at bottom just as arbitrary or pragmatic a matter as one's adoption of a new brand of set theory or even a new system of bookkeeping. | |
| From: Willard Quine (Carnap and Logical Truth [1954], x) | |
| A reaction: This spells out clearly the strongly pragmatist vein in Quine's thinking. |
| 12134 | Matter is the substratum, which supports both coming-to-be and alteration [Aristotle] |
| Full Idea: Matter, in the proper sense of the term, is to be identified with the substratum which is receptive of coming-to-be and passing-away; but the substratum of the remaining kinds of change is also matter, because these substrata receive contraries. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 320a03) | |
| A reaction: This must be compared with his complex discussion of the role of matter in his Metaphysics, where he has introduced 'form' as the essence of things. I don't think the two texts are inconsistent, but it's tricky... See Idea 12133 on types of change. |
| 16572 | Does the pure 'this' come to be, or the 'this-such', or 'so-great', or 'somewhere'? [Aristotle] |
| Full Idea: The question might be raised whether substance (i.e. the 'this') comes-to-be at all. Is it not rather the 'such', the 'so-great', or the 'somewhere', which comes-to-be? | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 317b21) | |
| A reaction: This is interesting because it pulls the 'tode ti', the 'this-such', apart, showing that he does have a concept of a pure 'this', which seems to constitute the basis of being ('ousia'). We can say 'this thing', or 'one of these things'. |
| 16573 | Philosophers have worried about coming-to-be from nothing pre-existing [Aristotle] |
| Full Idea: In addition, coming-to-be may proceed out of nothing pre-existing - a thesis which, more than any other, preoccupied and alarmed the earliest philosophers. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 317b29) | |
| A reaction: This is the origin of the worry about 'ex nihilo' coming-to-be. Christians tended to say that only God could create in this way. |
| 13214 | The substratum changing to a contrary is the material cause of coming-to-be [Aristotle] |
| Full Idea: The substratum [hupokeimenon?] is the material cause of the continuous occurrence of coming-to-be, because it is such as to change from contrary to contrary. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 319a19) | |
| A reaction: Presumably Aristotle will also be seeking the 'formal' cause as well as the 'material' cause (not to mention the 'efficient' and 'final' causes). |
| 13215 | If a perceptible substratum persists, it is 'alteration'; coming-to-be is a complete change [Aristotle] |
| Full Idea: There is 'alteration' when the substratum is perceptible and persists, but changes in its own properties. ...But when nothing perceptible persists in its identity as a substratum, and the thing changes as a whole, it is coming-to-be of a substance. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 319b11-17) | |
| A reaction: [compressed] Note that a substratum can be perceptible - it isn't just some hidden mystical I-know-not-what (as Locke calls it). This whole text is a wonderful source on the subject of physical change. Note too the reliance on what is perceptible. |
| 9001 | Frege moved Kant's question about a priori synthetic to 'how is logical certainty possible?' [Quine] |
| Full Idea: When Kant's arithmetical examples of a priori synthetic judgements were sweepingly disqualified by Frege's reduction of arithmetic to logic, attention moved to the less tendentious and logically prior question 'How is logical certainty possible?' | |
| From: Willard Quine (Carnap and Logical Truth [1954], I) | |
| A reaction: A nice summary of the story so far, from someone who should know. This still leaves the question open of whether any synthetic truths can be derived from the logical certainties which are available. |
| 9005 | Examination of convention in the a priori begins to blur the distinction with empirical knowledge [Quine] |
| Full Idea: In trying to make sense of the role of convention in a priori knowledge, the very distinction between a priori and empirical begins to waver and dissolve. | |
| From: Willard Quine (Carnap and Logical Truth [1954], VI) | |
| A reaction: This is the next stage in the argument after Wittgenstein presents the apriori as nothing more than what arises from truth tables. The rationalists react by taking us back to the original 'natural light of reason' view. Then we go round again... |
| 16717 | Which of the contrary features of a body are basic to it? [Aristotle] |
| Full Idea: What sorts of contrarities, and how many of them, are to be accounted 'originative sources' of body? | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 329b04) | |
| A reaction: Pasnau says these pages of Aristotle are the source of the doctrine of primary and secondary qualities. Essentially, hot, cold, wet and dry are his four primary qualities. |
| 13216 | Matter is the limit of points and lines, and must always have quality and form [Aristotle] |
| Full Idea: The matter is that of which points and lines are limits, and it is something that can never exist without quality and without form. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 320b16) | |
| A reaction: There seems to be a contradiction here somewhere. Matter has to be substantial enough to have a form, and yet seems to be the collective 'limit' of the points and lines. I wonder what 'limit' is translating? Sounds a bit too modern. |
| 17994 | The primary matter is the substratum for the contraries like hot and cold [Aristotle] |
| Full Idea: We must reckon as an 'orginal source' and as 'primary' the matter which underlies, though it is inseparable from the contrary qualities: for 'the hot' is not matter for 'the cold' nor 'cold' for 'hot', but the substratum is matter for them both. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 329a30) | |
| A reaction: A much discussed passage. |
| 13224 | There couldn't be just one element, which was both water and air at the same time [Aristotle] |
| Full Idea: No one supposes a single 'element' to persist, as the basis of all, in such a way that it is Water as well as Air (or any other element) at the same time. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 332a09) | |
| A reaction: Of course, we now think that oxygen is a key part of both water and of air, but Aristotle's basic argument still seems right. How could multiplicity be explained by a simply unity? The One is cool, but explains nothing. |
| 16594 | The Four Elements must change into one another, or else alteration is impossible [Aristotle] |
| Full Idea: These bodies (Fire, Water and the like) change into one another (and are not immutable as Empedocles and other thinkers assert, since 'alteration' would then have been impossible). | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 329b1) | |
| A reaction: This is why Aristotle proposes that matter [hule] underlies the four elements. Gill argues that by matter Aristotle means the elements. |
| 13223 | Fire is hot and dry; Air is hot and moist; Water is cold and moist; Earth is cold and dry [Aristotle] |
| Full Idea: The four couples of elementary qualities attach themselves to the apparently 'simple' bodies (Fire, Air, Earth, Water). Fire is hot and dry, whereas Air is hot and moist (being a sort of aqueous vapour); Water is cold and moist, and Earth is cold and dry. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 330b02) | |
| A reaction: This is the traditional framework accepted throughout the middle ages, and which had a huge influence on medicine. It all looks rather implausible now. Aristotle was a genius, but not critical enough about evidence. |
| 13210 | Wood is potentially divided through and through, so what is there in the wood besides the division? [Aristotle] |
| Full Idea: If having divided a piece of wood I put it together, it is equal to what it was and is one. This is so whatever the point at which I cut the wood. The wood is therefore divided potentially through and through. So what is in the wood besides the division? | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 316b11) | |
| A reaction: Part of a very nice discussion of the implications of the thought experiment of cutting something 'through and through'. It seems to me that the arguments are still relevant, in the age of quarks, electrons and strings. |
| 13211 | If a body is endlessly divided, is it reduced to nothing - then reassembled from nothing? [Aristotle] |
| Full Idea: Dividing a body at all points might actually occur, so the body will be both actually indivisible and potentially divided. Then nothing will remain and the body passes into what is incorporeal. So it might be reassembled out of points, or out of nothing. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 316b24) | |
| A reaction: [a bit compressed] This sounds like an argument in favour of atomism, but Aristotle was opposed to that view. He is aware of the contradictions that seem to emerge with infinite division. Graham Priest is interesting on the topic. |
| 13220 | Bodies are endlessly divisible [Aristotle] |
| Full Idea: Bodies are divisible through and through. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 326b27) | |
| A reaction: This is Aristotle's flat rejection of atomism, arrived at after several sustained discussions, in this text and elsewhere. I don't think we are in a position to say that Aristotle is wrong. |
| 12709 | Motion is not absolute, but consists in relation [Leibniz] |
| Full Idea: In reality motion is not something absolute, but consists in relation. | |
| From: Gottfried Leibniz (On Motion [1677], A6.4.1968), quoted by Daniel Garber - Leibniz:Body,Substance,Monad 3 | |
| A reaction: It is often thought that motion being relative was invented by Einstein, but Leibniz wholeheartedly embraced 'Galilean relativity', and refused to even consider any absolute concept of motion. Acceleration is a bit trickier than velocity. |
| 13228 | There is no time without movement [Aristotle] |
| Full Idea: There can be no time without movement. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 337a24) | |
| A reaction: See Shoemaker's nice thought experiment as a challenge to this. Intuition seems to cry out that if movement stopped for a moment, that would not stop time, even though there was no way to measure its passing. |
| 16595 | If each thing can cease to be, why hasn't absolutely everything ceased to be long ago? [Aristotle] |
| Full Idea: If some one of the things 'which are' is constantly disappearing, why has not the whole of 'what is' been used up long ago and vanished away - assuming of course that the material of all the several comings-to-be was infinite? | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 318a17) | |
| A reaction: This thought is the basis of Aquinas's Third Way for proving the existence of God (as the force which prevents the vicissitudes of nature from sliding into oblivion). |
| 13227 | Being is better than not-being [Aristotle] |
| Full Idea: Being is better than not-being. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 336b29) | |
| A reaction: [see also Metaphysics 1017a07 ff, says the note] This peculiar assumption is at the heart of the ontological argument. Is the existence of the plague bacterium, or of Satan, or of mass-murderers, superior? |
| 13226 | An Order controls all things [Aristotle] |
| Full Idea: There is an Order controlling all things. | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 336b13) | |
| A reaction: Presumably the translator provides the capital letter. How do we get from 'there is an order in all things' to 'there is an order which controls all things'? |