50 ideas
12274 | Begin examination with basics, and subdivide till you can go no further [Aristotle] |
Full Idea: The examination must be carried on and begin from the primary classes and then go on step by step until further division is impossible. | |
From: Aristotle (Topics [c.331 BCE], 109b17) | |
A reaction: This is a good slogan for the analytic approach to thought. I take Aristotle (or possibly Socrates) to be the father of analysis, not Frege (though see Idea 9840). (He may be thinking of the tableau method of proof). |
12260 | Dialectic starts from generally accepted opinions [Aristotle] |
Full Idea: Reasoning is dialectical which reasons from generally accepted opinions. | |
From: Aristotle (Topics [c.331 BCE], 100a30) | |
A reaction: This is right at the heart of Aristotle's philosophical method, and Greek thinking generally. There are nice modern debates about 'folk' understanding, derived from science (e.g. quantum theory) which suggest that starting from normal views is a bad idea. |
12291 | There can't be one definition of two things, or two definitions of the same thing [Aristotle] |
Full Idea: There cannot possibly be one definition of two things, or two definitions of the same thing. | |
From: Aristotle (Topics [c.331 BCE], 154a11) | |
A reaction: The second half of this is much bolder and more controversial, and plenty of modern thinkers would flatly reject it. Are definitions contextual, that is, designed for some specific human purpose. Must definitions be of causes? |
12292 | Definitions are easily destroyed, since they can contain very many assertions [Aristotle] |
Full Idea: A definition is the easiest of all things to destroy; for, since it contains many assertions, the opportunities which it offers are very numerous, and the more abundant the material, the more quickly the reasoning can set to work. | |
From: Aristotle (Topics [c.331 BCE], 155a03) | |
A reaction: I quote this to show that Aristotle expected many definitions to be very long affairs (maybe even of book length?) |
12261 | Differentia are generic, and belong with genus [Aristotle] |
Full Idea: The differentia, being generic in character, should be ranged with the genus. | |
From: Aristotle (Topics [c.331 BCE], 101b18) | |
A reaction: This does not mean that naming the differentia amounts to mere classification. I presume we can only state individual differences by using a language which is crammed full of universals. |
12263 | 'Genus' is part of the essence shared among several things [Aristotle] |
Full Idea: A 'genus' is that which is predicated in the category of essence of several things which differ in kind. | |
From: Aristotle (Topics [c.331 BCE], 102a32) | |
A reaction: Hence a genus is likely to be expressed by a universal, a one-over-many. A particular will be a highly individual collection of various genera, but what ensures the uniqueness of each thing, if they are indiscernible? |
12272 | We describe the essence of a particular thing by means of its differentiae [Aristotle] |
Full Idea: We usually isolate the appropriate description of the essence of a particular thing by means of the differentiae which are peculiar to it. | |
From: Aristotle (Topics [c.331 BCE], 108b05) | |
A reaction: I take this to be important for showing the definition is more than mere categorisation. A good definition homes in the particular, by gradually narrowing down the differentiae. |
12279 | The differentia indicate the qualities, but not the essence [Aristotle] |
Full Idea: No differentia indicates the essence [ti estin], but rather some quality, such as 'pedestrian' or 'biped'. | |
From: Aristotle (Topics [c.331 BCE], 122b17) | |
A reaction: We must disentangle this, since essence is what is definable, and definition seems to give us the essence, and yet it appears that definition only requires genus and differentia. Differentiae seem to be both generic and fine-grained. See Idea 12280! |
12283 | In definitions the first term to be assigned ought to be the genus [Aristotle] |
Full Idea: In definitions the first term to be assigned ought to be the genus. | |
From: Aristotle (Topics [c.331 BCE], 132a12) | |
A reaction: We mustn't be deluded into thinking that nothing else is required. I take the increasing refinement of differentiae to be where the real action is. The genus gives you 70% of the explanation. |
12289 | The genera and the differentiae are part of the essence [Aristotle] |
Full Idea: The genera and the differentiae are predicated in the category of essence. | |
From: Aristotle (Topics [c.331 BCE], 153a19) | |
A reaction: The definition is words, and the essence is real, so our best definition might not fully attain to the essence. Aristotle has us reaching out to the world through our definitions. |
12285 | The definition is peculiar to one thing, not common to many [Aristotle] |
Full Idea: The definition ought to be peculiar to one thing, not common to many. | |
From: Aristotle (Topics [c.331 BCE], 149b24) | |
A reaction: I take this to be very important, against those who think that definition is no more than mere categorisation. To explain, you must get down to the level of the individual. We must explain that uniquely docile tiger. |
11261 | Puzzles arise when reasoning seems equal on both sides [Aristotle] |
Full Idea: The equality of opposite reasonings is the cause of aporia; for it is when we reason on both [sides of a question] and it appears to us that everything can come about either way, that we are in a state of aporia about which of the two ways to take up. | |
From: Aristotle (Topics [c.331 BCE], 145b17), quoted by Vassilis Politis - Aristotle and the Metaphysics 3.1 | |
A reaction: Other philosophers give up on the subject in this situation, but I love Aristotle because he takes this to be the place where philosophy begins. |
12273 | Unit is the starting point of number [Aristotle] |
Full Idea: They say that the unit [monada] is the starting point of number (and the point the starting-point of a line). | |
From: Aristotle (Topics [c.331 BCE], 108b30) | |
A reaction: Yes, despite Frege's objections in the early part of the 'Grundlagen' (1884). I take arithmetic to be rooted in counting, despite all abstract definitions of number by Frege and Dedekind. Identity gives the unit, which is countable. See also Topics 141b9 |
12267 | There are ten categories: essence, quantity, quality, relation, place, time, position, state, activity, passivity [Aristotle] |
Full Idea: The four main types of predicates fall into ten categories: essence, quantity, quality, relation, place, time, position, state, activity, passivity. | |
From: Aristotle (Topics [c.331 BCE], 103b20) | |
A reaction: These are the standard ten categories of Aristotle. He is notable for the divisions not being sharp, and ten being a rough total. He is well aware of the limits of precision in such matters. |
12282 | An individual property has to exist (in past, present or future) [Aristotle] |
Full Idea: If it does not at present exist, or, if it has not existed in the past, or if it is not going to exist in the future, it will not be a property [idion] at all. | |
From: Aristotle (Topics [c.331 BCE], 129a27) | |
A reaction: This seems to cramp our style in counterfactual discussion. Can't we even mention an individual property if we believe that it will never exist. Utopian political discussion will have to cease! |
12264 | An 'accident' is something which may possibly either belong or not belong to a thing [Aristotle] |
Full Idea: An 'accident' [sumbebekos] is something which may possibly either belong or not belong to any one and the self-same thing, such as 'sitting posture' or 'whiteness'. This is the best definition, because it tells us the essential meaning of the term itself. | |
From: Aristotle (Topics [c.331 BCE], 102b07) | |
A reaction: Thus a car could be red, or not red. Accidents are contingent. It does not follow that necessary properties are essential (see Idea 12262). There are accidents [sumbebekos], propria [idion] and essences [to ti en einai]. |
17954 | Essence is a thing's necessities, but what about its possibilities (which may not be realised)? [Vetter] |
Full Idea: Essence is, as it were, necessity rooted in things, ...but how about possibility rooted in things? ...Having the potential to Φ, unlike being essentially Φ, does not entail being actually Φ. | |
From: Barbara Vetter (Essence and Potentiality [2010], §2) | |
A reaction: To me this invites the question 'what is it about the entity which endows it with its rooted possibilities?' A thing has possibilities because it has a certain nature (at a given time). |
12280 | Genus gives the essence better than the differentiae do [Aristotle] |
Full Idea: In assigning the essence [ti estin], it is more appropriate to state the genus than the differentiae; for he who describes 'man' as an 'animal' indicates his essence better than he who describes him as 'pedestrian'. | |
From: Aristotle (Topics [c.331 BCE], 128a24) | |
A reaction: See Idea 12279. This idea is only part of the story. My reading of this is simply that assigning a genus gives more information. We learn more about him when we say he is a man than when we say he is Socrates. |
13269 | In the case of a house the parts can exist without the whole, so parts are not the whole [Aristotle] |
Full Idea: In the case of a house, where the process of compounding the parts is obvious, though the parts exist, there is no reason why the whole should not be non-existent, and so the parts are not the same as the whole. | |
From: Aristotle (Topics [c.331 BCE], 150a19) | |
A reaction: Compare buying a piece of furniture, and being surprised to discover, when it is delivered, that it is self-assembly. This idea is a simple refutation of the claims of classical mereology, that wholes are just some parts. Aristotle uses modal claims. |
12284 | Everything that is has one single essence [Aristotle] |
Full Idea: Everything that is has one single essence [en esti to einai]. | |
From: Aristotle (Topics [c.331 BCE], 141a36) | |
A reaction: Does this include vague objects, and abstract 'objects'? Sceptics might ask what grounds this claim. Does Dr Jeckyll have two essences? |
17953 | Real definition fits abstracta, but not individual concrete objects like Socrates [Vetter] |
Full Idea: I can understand the notion of real definition as applying to (some) abstact entities, but I have no idea how to apply it to a concrete object such as Socrates or myself. | |
From: Barbara Vetter (Essence and Potentiality [2010], §1) | |
A reaction: She is objecting to Kit Fine's account of essence, which is meant to be clearer than the normal account of essences based on necessities. Aristotle implies that definitions get fuzzy when you reach the level of the individual. |
17952 | Modal accounts make essence less mysterious, by basing them on the clearer necessity [Vetter] |
Full Idea: The modal account was meant, I take it, to make the notion of essence less mysterious by basing it on the supposedly better understood notion of necessity. | |
From: Barbara Vetter (Essence and Potentiality [2010], §1) |
12262 | An 'idion' belongs uniquely to a thing, but is not part of its essence [Aristotle] |
Full Idea: A property [idion] is something which does not show the essence of a thing but belongs to it alone. ...No one calls anything a property which can possibly belong to something else. | |
From: Aristotle (Topics [c.331 BCE], 102a18) | |
A reaction: [See Charlotte Witt 106 on this] 'Property' is clearly a bad translation for such an individual item. Witt uses 'proprium', which is a necessary but nonessential property of something. Necessity is NOT the hallmark of essence. See Idea 12266. |
12290 | Destruction is dissolution of essence [Aristotle] |
Full Idea: Destruction is a dissolution of essence. | |
From: Aristotle (Topics [c.331 BCE], 153b30) | |
A reaction: [plucked from context!] I can't think of a better way to define destruction, in order to distinguish it from damage. A vase is destroyed when its essential function cannot be recovered. |
12286 | If two things are the same, they must have the same source and origin [Aristotle] |
Full Idea: When things are absolutely the same, their coming-into-being and destruction are also the same and so are the agents of their production and destruction. | |
From: Aristotle (Topics [c.331 BCE], 152a02) | |
A reaction: Thus Queen Elizabeth II has to be the result of that particular birth, and from those particular parents, as Kripke says? The inverse may not be true. Do twins have a single origin? Things that fission and then re-fuse differently? etc |
12266 | 'Same' is mainly for names or definitions, but also for propria, and for accidents [Aristotle] |
Full Idea: 'The same' is employed in several senses: its principal sense is for same name or same definition; a second sense occurs when sameness is applied to a property [idiu]; a third sense is applied to an accident. | |
From: Aristotle (Topics [c.331 BCE], 103a24-33) | |
A reaction: [compressed] 'Property' is better translated as 'proprium' - a property unique to a particular thing, but not essential - see Idea 12262. Things are made up of essence, propria and accidents, and three ways of being 'the same' are the result. |
12287 | Two identical things have the same accidents, they are the same; if the accidents differ, they're different [Aristotle] |
Full Idea: If two things are the same then any accident of one must also be an accident of the other, and, if one of them is an accident of something else, so must the other be also. For, if there is any discrepancy on these points, obviously they are not the same. | |
From: Aristotle (Topics [c.331 BCE], 152a36) | |
A reaction: So what is always called 'Leibniz's Law' should actually be 'Aristotle's Law'! I can't see anything missing from the Aristotle version, but then, since most people think it is pretty obvious, you would expect the great stater of the obvious to get it. |
12288 | Numerical sameness and generic sameness are not the same [Aristotle] |
Full Idea: Things which are the same specifically or generically are not necessarily the same or cannot possibly be the same numerically. | |
From: Aristotle (Topics [c.331 BCE], 152b32) | |
A reaction: See also Idea 12266. This looks to me to be a pretty precise anticipation of Peirce's type/token distinction, but without the terminology. It is reassuring that Aristotle spotted it, as that makes it more likely to be a genuine distinction. |
17959 | Metaphysical necessity is even more deeply empirical than Kripke has argued [Vetter] |
Full Idea: We support the views of metaphysical modality on which metaphysical necessity is an even more deeply empirical matter than Kripke has argued. | |
From: Barbara Vetter (Essence and Potentiality [2010], p.2) | |
A reaction: [co-author E. Viebahn] This seems to pinpoint the spirit of scientific essentialism. She cites Bird and Shoemaker. If it is empirical, doesn't that make it a matter of epistemology, and hence further from absolute necessity? |
12259 | Reasoning is when some results follow necessarily from certain claims [Aristotle] |
Full Idea: Reasoning [sullogismos] is a discussion in which, certain things having been laid down, something other than these things necessarily results through them. | |
From: Aristotle (Topics [c.331 BCE], 100a25) | |
A reaction: This is cited as the standard statement of the nature of logical necessity. One might challenge either the very word 'necessary', or the exact sense of the word employed here. Is it, in fact, metaphysical, or merely analytic? |
17955 | Possible worlds allow us to talk about degrees of possibility [Vetter] |
Full Idea: The apparatus of possible worlds affords greater expressive power than mere talk of possibility and necessity. In particular, possible worlds talk allows us to introduce degrees of possibility. | |
From: Barbara Vetter (Essence and Potentiality [2010], §3) | |
A reaction: A nice feature, but I'm not sure that either the proportion of possible worlds or the closeness of possible worlds captures what we actually mean by a certain degree of possibility. There is 'accidental closeness', or absence of contingency. See Vetter. |
17957 | Maybe possibility is constituted by potentiality [Vetter] |
Full Idea: We should look at the claim that possibility is constituted by potentiality. | |
From: Barbara Vetter (Essence and Potentiality [2010], §4) | |
A reaction: A problem that comes to mind is possibilities arising from coincidence. The whole of reality must be described, to capture all the possibilities for a particular thing. So potentialities of what? Nice thought, though. |
17958 | The apparently metaphysically possible may only be epistemically possible [Vetter] |
Full Idea: Some of what metaphysicians take to be metaphysically possible turns out to be only epistemically possible. | |
From: Barbara Vetter (Essence and Potentiality [2010], §4) | |
A reaction: A nice clear expression of the increasingly common view that conceivability may be a limited way to grasp possibility. |
17956 | Closeness of worlds should be determined by the intrinsic nature of relevant objects [Vetter] |
Full Idea: The closeness of possible worlds should be determined by similarity in the intrinsic constitution of whatever object it is whose potentialities are at issue. | |
From: Barbara Vetter (Essence and Potentiality [2010], §3) | |
A reaction: Nice thought. This seems to be the essentialist approach to possible worlds, but it makes the natures of the objects more fundamental than the framework of the worlds. She demurs because there are also extrinsic potentialities. |
12271 | Induction is the progress from particulars to universals [Aristotle] |
Full Idea: Induction is the progress from particulars to universals; if the skilled pilot is the best pilot and the skilled charioteer the best charioteer, then, in general, the skilled man is the best man in any particular sphere. | |
From: Aristotle (Topics [c.331 BCE], 105a15) | |
A reaction: It is a bit unclear whether we are deriving universal concepts, or merely general truths. Need general truths be absolute or necessary truths? Presumably occasionally the best person is not the most skilled, as in playing a musical instrument. |
12293 | We say 'so in cases of this kind', but how do you decide what is 'of this kind'? [Aristotle] |
Full Idea: When it is necessary to establish the universal, people use the expression 'So in all cases of this kind'; but it is one of the most difficult tasks to define which of the terms proposed are 'of this kind' and which are not. | |
From: Aristotle (Topics [c.331 BCE], 157a25) | |
A reaction: It is particularly hard if induction is expressed as the search for universals, since the kind presumably is the universal, so the universal must be known before the induction can apply, which really is the most frightful nuisance for truth-seekers. |
12276 | Justice and self-control are better than courage, because they are always useful [Aristotle] |
Full Idea: Justice [dikaiosune] and self-control [sophrosune] are preferable to courage, for the first two are always useful, but courage only sometimes. | |
From: Aristotle (Topics [c.331 BCE], 117a36) | |
A reaction: One could challenge his criterion. What of something which is absolutely vital on occasions, against something which is very mildly useful all the time? You may survive without justice, but not without courage. Compare Idea 12277. |
12277 | Friendship is preferable to money, since its excess is preferable [Aristotle] |
Full Idea: Friendship is preferable to money; for excess of friendship is preferable to excess of money. | |
From: Aristotle (Topics [c.331 BCE], 118b07) | |
A reaction: Compare Idea 12276, which gives a different criterion for choosing between virtues. This idea is an interesting qualification of the doctrine of the mean. |
12275 | We value friendship just for its own sake [Aristotle] |
Full Idea: We value friendship for its own sake, even if we are not likely to get anything else from it. | |
From: Aristotle (Topics [c.331 BCE], 117a03) | |
A reaction: In 'Ethics' he distinguishes some friendships which don't meet this requirement. Presumably true friendships survive all vicissitudes (except betrayal), but that makes such things fairly rare. |
12281 | Man is intrinsically a civilized animal [Aristotle] |
Full Idea: It is an essential [kath' auto] property of man to be 'by nature a civilized animal'. | |
From: Aristotle (Topics [c.331 BCE], 128b17) | |
A reaction: I take this, along with man being intrinsically rational, to be the foundation of Aristotelian ethics. Given that we are civilized, self-evident criteria emerge for how to be good at it. A good person is, above all, a good citizen. |
12265 | All water is the same, because of a certain similarity [Aristotle] |
Full Idea: Any water is said to be specifically the same as any other water because it has a certain similarity to it. | |
From: Aristotle (Topics [c.331 BCE], 103a20) | |
A reaction: (Cf. Idea 8153) It take this to be the hallmark of a natural kind, and we should not lose sight of it in the midst of discussions about rigid designation and essential identity. Tigers are only a natural kind insofar as they are indistinguishable. |
12278 | 'Being' and 'oneness' are predicated of everything which exists [Aristotle] |
Full Idea: 'Being' and 'oneness' are predicated of everything which exists. | |
From: Aristotle (Topics [c.331 BCE], 121a18) | |
A reaction: Is 'oneness' predicated of water? So existence always was a predicate, it seems, until Kant told us it wasn't. That existence is a quantifier, not a predicate, seems to be up for question again these days. |
21332 | We don't get a love of 'order' from nature - which is thoroughly chaotic [Mill] |
Full Idea: Even the love of 'order' which is thought to be a following of the ways of nature is in fact a contradiction of them. All which people are accustomed to deprecate as 'disorder' is precisely a counterpart of nature's ways. | |
From: John Stuart Mill (Nature and Utility of Religion [1874], p.116) | |
A reaction: The Greeks elevated the idea that the cosmos was orderly, but almost entirely based on the regular movement of the planets. They turned a blind eye to the messy bits of nature. As you magnify nature, order and chaos seem to alternate. |
21333 | Evil comes from good just as often as good comes from evil [Mill] |
Full Idea: If good frequently comes out of evil, the converse fact, evil coming out of good, is equally common. | |
From: John Stuart Mill (Nature and Utility of Religion [1874], p.117) | |
A reaction: Mill surmises that on the whole good comes from good, and evil from evil, but the point is that the evidence doesn't favour the production of increased good. |
21335 | Belief that an afterlife is required for justice is an admission that this life is very unjust [Mill] |
Full Idea: The necessity of redressing the balance [of injustice] is deemed one of the strongest arguments for another life after death, which amounts to an admission that the order of things in this life is often an example of injustice, not justice. | |
From: John Stuart Mill (Nature and Utility of Religion [1874]) | |
A reaction: It certainly seems that an omnipotent God could administer swift justice in this life. If the whole point is that we need freedom of will, then why is justice administered at a much later date? The freedom seems to be illusory. |
21334 | No necessity ties an omnipotent Creator, so he evidently wills human misery [Mill] |
Full Idea: If a Creator is assumed to be omnipotent, if he bends to a supposed necessity, he himself makes the necessity which he bends to. If the maker of the world can all that he will, he wills misery, and there is no escape from the conclusion. | |
From: John Stuart Mill (Nature and Utility of Religion [1874], p.119) | |
A reaction: If you add that the Creator is supposed to be perfectly benevolent, you arrive at the paradox which Mackie spells out. Is the correct conclusion that God exists, and is malevolent? Mill doesn't take that option seriously. |
21329 | Nature dispenses cruelty with no concern for either mercy or justice [Mill] |
Full Idea: All of this [cruel killing] nature does with the most supercilious disregard both of mercy and of justice, emptying her shafts upon the best and noblest indifferently with the meanest and worst | |
From: John Stuart Mill (Nature and Utility of Religion [1874], p.115) | |
A reaction: The existence of an afterlife at least offers an opportunity to rectify any injustice, but that hardly meets the question of why there was injustice in the first place. It would be odd if it actually is justice, but none of us can see why that is so. |
21328 | Killing is a human crime, but nature kills everyone, and often with great tortures [Mill] |
Full Idea: Killing, the most criminal act recognised by human laws, nature does once to every being that lives, and frequently after protracted tortures such as the greatest know monsters purposely inflicted on their living fellow creatures | |
From: John Stuart Mill (Nature and Utility of Religion [1874], p.115) | |
A reaction: We certainly don't condemn lions for savaging gazelles, but the concept of a supreme mind controlling nature forces the question. Theology needs consistency between human and divine morality, and the supposed derivation of the former from the latter. |
21330 | Nature makes childbirth a miserable experience, often leading to the death of the mother [Mill] |
Full Idea: In the clumsy provision which nature has made for the perpetual renewal of animal life, ...no human being ever comes into the world but another human being is literally stretched on the rack for hours or day, not unfrequently issuing in death. | |
From: John Stuart Mill (Nature and Utility of Religion [1874], p.116) | |
A reaction: This is a very powerful example, which is rarely cited in modern discussions. |
21331 | Hurricanes, locusts, floods and blight can starve a million people to death [Mill] |
Full Idea: Nature often takes the means by which we live. A single hurricane, a flight of locusts, or an inundation, or a trifling chemical change in an edible root, starve a million people. | |
From: John Stuart Mill (Nature and Utility of Religion [1874], p.116) | |
A reaction: [second sentence compressed] The 'edible root' is an obvious reference to the Irish potato famine. Some desertification had human causes, but these are telling examples. |