86 ideas
| 1695 | Without extensive examination firm statements are hard, but studying the difficulties is profitable [Aristotle] |
| Full Idea: It is hard to make firm statements on these questions without having examined them many times, but to have gone through the various difficulties is not unprofitable. | |
| From: Aristotle (Categories [c.331 BCE], 08b23) | |
| A reaction: Suggesting that philosophy is more like drawing the map than completing the journey. |
| 5196 | Philosophy is a department of logic [Ayer] |
| Full Idea: Philosophy is a department of logic. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.2) | |
| A reaction: Personally I would invert that. Philosophy is concerned with human rationality, of which precise logic appears to be a rather limited subdivision. I see philosophy as the 'master' subject, not the 'servant' subject (as Locke had implied). |
| 20771 | Six parts: dialectic, rhetoric, ethics, politics, physics, theology [Cleanthes, by Diog. Laertius] |
| Full Idea: Cleanthes says there are six parts: dialectic, rhetoric, ethics, politics, physics, and theology. | |
| From: report of Cleanthes (fragments/reports [c.270 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 07.41 | |
| A reaction: This was a minority view, as most stoics agreed with Zeno and Chrysippus that there are three main topics. Nowadays there is little discussion of the 'parts' of philosophy, but the recent revival of meta-philosophy should encourage it. |
| 5189 | Philosophers should abandon speculation, as philosophy is wholly critical [Ayer] |
| Full Idea: We can overthrow speculative philosophy, and see that the function of philosophy is wholly critical. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.2) | |
| A reaction: This seems to imply that we CAN speculate, which appeared to be rendered impossible by the verification principle. Personally I think speculation is central to philosophy, but Ayer should always stand as a warning against bogus truth-claims. |
| 7919 | Humeans rejected the a priori synthetic, and so rejected even Kantian metaphysics [Ayer, by Macdonald,C] |
| Full Idea: Thinkers from Hume to the logical positivists took exception to Kant's view that some synthetic propositions could be known a priori, and so rejected the possibility of metaphysics as Kant conceived of it. | |
| From: report of A.J. Ayer (Language,Truth and Logic [1936]) by Cynthia Macdonald - Varieties of Things Ch.1 | |
| A reaction: See Idea 7918 for Kant's epistemological view of metaphysics. This strikes me as a big misunderstanding by empiricists, even though they are quite right to insist on evidence and proof. Metaphysics is essential, but its excess is the worst nonsense. |
| 5195 | Critics say analysis can only show the parts, and not their distinctive configuration [Ayer] |
| Full Idea: Critics say an analyst is obliged by his atomistic metaphysics to regard an object consisting of parts a, b, c and d in a distinctive configuration as being simply a+b+c+d, and thus giving an entirely false account of its nature. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.2) | |
| A reaction: Ayer refers the critics to gestatl psychology. Personally I prefer to talk about the ontology rather than the psychology. If we include (as Russell suggests) relations as part of the analysis, there seems to be no problem. |
| 5179 | Philosophy deals with the questions that scientists do not wish to handle [Ayer] |
| Full Idea: If there are any questions which science leaves it to philosophy to answer, a straightforward process of elimination must lead to their discovery. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.1) | |
| A reaction: This is characteristic of the feeble-mindedness that British philosophy slipped into in the age of Wittgenstein, and for a while thereafter. Personally I regard scientists as servants, who are sent off on exploratory errands, and must report back. |
| 1698 | Both sides of contraries need not exist (as health without sickness, white without black) [Aristotle] |
| Full Idea: With contraries it is not necessary if one exists for the other to exist too, for if everyone were well health would exist but not sickness, and if everything were white whiteness would exist but not black. | |
| From: Aristotle (Categories [c.331 BCE], 14a06) |
| 1697 | The contrary of good is bad, but the contrary of bad is either good or another evil [Aristotle] |
| Full Idea: What is contrary to a good thing is necessarily bad, as we see with health and sickness. But the contrary of bad is sometimes good, sometimes not, as we see with excess, opposed by both deficiency and moderation. | |
| From: Aristotle (Categories [c.331 BCE], 13b36) |
| 11034 | The differentiae of genera which are different are themselves different in kind [Aristotle] |
| Full Idea: The differentiae of genera which are different and not subordinate one to the other are themselves different in kind. | |
| From: Aristotle (Categories [c.331 BCE], 01b16) | |
| A reaction: This seems to be indicating a category mistake, as he warns us not to attribute the wrong kind of differentiae to something we are picking out. |
| 18367 | A true existence statement has its truth caused by the existence of the thing [Aristotle] |
| Full Idea: Whereas the true statement [that there is a man] is in no way the cause of the actual thing's existence, the actual thing does seem in some way the cause of the statement's being true. | |
| From: Aristotle (Categories [c.331 BCE], 14b18) | |
| A reaction: Armstrong offers this as the earliest statement of the truthmaker principle. Notice the cautious qualification 'seem in some way'. The truthmaker dependence seems even clearer in falsemaking, where the death of the man falsifies the statement. |
| 4749 | We cannot analyse the concept of 'truth', because it is simply a mark that a sentence is asserted [Ayer] |
| Full Idea: When one says that "Queen Anne is dead" is true or false, these terms 'true' and 'false' connote nothing, but function in the sentence simply as marks of assertion and denial, so there is no sense in asking us to analyse the concept of 'truth'. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.5) | |
| A reaction: "I am ill" may be true when you say it, and false when I say it. The word 'true' has a useful function in 'x is true if y'. "If that is true, Freddie, I will hit you". |
| 11033 | Predications of predicates are predications of their subjects [Aristotle] |
| Full Idea: Whenever one thing is predicated of another as of a subject, all things said of what is predicated will be said of the subject also. | |
| From: Aristotle (Categories [c.331 BCE], 01b10) |
| 11044 | One is prior to two, because its existence is implied by two [Aristotle] |
| Full Idea: One is prior to two because if there are two it follows at once that there is one, whereas if there is one there is not necessarily two. | |
| From: Aristotle (Categories [c.331 BCE], 14a29) | |
| A reaction: The axiomatic introduction of a 'successor' to a number does not seem to introduce this notion of priority, based on inclusiveness. Introducing order by '>' also does not seem to indicate any logical priority. |
| 11042 | Parts of a line join at a point, so it is continuous [Aristotle] |
| Full Idea: A line is a continuous quantity. For it is possible to find a common boundary at which its parts join together, a point. | |
| From: Aristotle (Categories [c.331 BCE], 04b33) | |
| A reaction: This appears to be the essential concept of a Dedekind cut. It seems to be an open question whether a cut defines a unique number, but a boundary seems to be intrinsically unique. Aristotle wins again. |
| 11041 | Some quantities are discrete, like number, and others continuous, like lines, time and space [Aristotle] |
| Full Idea: Of quantities, some are discrete, others continuous. ...Discrete are number and language; continuous are lines, surfaces, bodies, and also, besides these, time and place. | |
| From: Aristotle (Categories [c.331 BCE], 04b20) | |
| A reaction: This distinction seems to me to be extremely illuminating, when comparing natural numbers with real numbers, and it is the foundation of the Greek view of mathematics. |
| 5202 | Maths and logic are true universally because they are analytic or tautological [Ayer] |
| Full Idea: The principles of logic and mathematics are true universally simply because we never allow them to be anything else; …in other words, they are analytic propositions, or tautologies. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.4) | |
| A reaction: This is obviously a very appealing idea, but it doesn's explain WHY we have invented these particular tautologies (which seem surprisingly useful). The 'science of patterns' can be empirical and a priori and useful (but not tautological). |
| 11286 | Primary being must be more than mere indeterminate ultimate subject of predication [Politis on Aristotle] |
| Full Idea: He criticises his 'Categories' view, because if primary being is simply the ultimate subject of predication the primary being is, in virtue of itself, something indeterminate; it would be a necessary but not a sufficient condition for primary being. | |
| From: comment on Aristotle (Categories [c.331 BCE]) by Vassilis Politis - Aristotle and the Metaphysics 7.5 | |
| A reaction: Thus, Politis argues, primary being is essence in the later work. The words 'substance' and 'ousia' cause confusion here, and must be watched closely. Wedin argues that Aristotle merely develops his 'Categories' view, but most disagree. |
| 1700 | There are six kinds of change: generation, destruction, increase, diminution, alteration, change of place [Aristotle] |
| Full Idea: There are six kinds of change: generation, destruction, increase, diminution, alteration, change of place. A change in our affections would be an example of alteration. | |
| From: Aristotle (Categories [c.331 BCE], 15a13) |
| 1699 | A thing is prior to another if it implies its existence [Aristotle] |
| Full Idea: That from which the implication of existence does not hold reciprocally is thought to be prior. | |
| From: Aristotle (Categories [c.331 BCE], 14a32) | |
| A reaction: shadows and objects |
| 18366 | Of interdependent things, the prior one causes the other's existence [Aristotle] |
| Full Idea: For of things which reciprocate as to implication of existence, that which is in some way the cause of the other's existence might reasonably by called prior by nature. | |
| From: Aristotle (Categories [c.331 BCE], 14b12) | |
| A reaction: Not so clear when you seek examples. The bus is prior to its redness, but you can't have a colourless bus, so being coloured is prior to being a bus. Aristotle's example is a man being prior to the truths about him. |
| 6523 | Positivists regard ontology as either meaningless or stipulated [Ayer, by Robinson,H] |
| Full Idea: Positivists tend to be prejudiced against ontology, regarding very general questions about what sort of things exist either as meaningless, or as questions to be settled by stipulation. | |
| From: report of A.J. Ayer (Language,Truth and Logic [1936]) by Howard Robinson - Perception IX.4 | |
| A reaction: So much the worse for positivists, because they are missing all the fun. I consider one of the central activities of philosophy to be speculating about explanations. Ontology is at the heart of what explanation aims at. |
| 3311 | The categories (substance, quality, quantity, relation, action, passion, place, time) peter out inconsequentially [Benardete,JA on Aristotle] |
| Full Idea: The Aristotelian schedule of categories - substance, quality, quantity, relation, action, passion, place, time, and so forth - appears to peter out inconsequentially. | |
| From: comment on Aristotle (Categories [c.331 BCE]) by José A. Benardete - Metaphysics: the logical approach Ch.7 | |
| A reaction: Compare Idea 5544 for Kant's attempt to classify categories. Personally I like the way Aristotle's 'peter out'. That seems to me a more plausible character for good metaphysics. |
| 11035 | There are ten basic categories for thinking about things [Aristotle] |
| Full Idea: Of things said without any combination, each signifies either substance or quantity or qualification or a relative or where or when or being-in-a-position or having or doing or being-affected. | |
| From: Aristotle (Categories [c.331 BCE], 01b25) | |
| A reaction: This sums up the earlier of Aristotle's two metaphysical view, and each of this categories is discussed in the present text. |
| 13121 | Substance,Quantity,Quality,Relation,Place,Time,Being-in-a-position,Having,Doing,Being affected [Aristotle, by Westerhoff] |
| Full Idea: Aristotle's list of ten categories proved to be the most influential scheme found in his works: Substance, Quantity, Quality, Relation, Place, Time, Being-in-a-position, Having, Doing, Being affected. | |
| From: report of Aristotle (Categories [c.331 BCE]) by Jan Westerhoff - Ontological Categories §01 |
| 16116 | Aristotle derived categories as answers to basic questions about nature, size, quality, location etc. [Aristotle, by Gill,ML] |
| Full Idea: Aristotle seems to have worked out his list of categories by considering various questions that one might ask about a particular object, such as What is it? How big is it? How is it qualified? And Where is it? | |
| From: report of Aristotle (Categories [c.331 BCE]) by Mary Louise Gill - Aristotle on Substance | |
| A reaction: Of course, to think of his questions, Aristotle already had categories in his mind. How would he approach a proposal to recategorise reality more efficiently? |
| 21345 | Aristotle said relations are not substances, so (if they exist) they must be accidents [Aristotle, by Heil] |
| Full Idea: Aristotle categorised relations as accidents - Socrates's whiteness, the sphericity of this ball - entities dependent on substances. Relations are not substances, so they must be, if anything at all, accidents. | |
| From: report of Aristotle (Categories [c.331 BCE], §7) by John Heil - Relations 'Historical' | |
| A reaction: Heil says this thought encouraged anti-realist views of relations, which became the norm until Russell. |
| 16155 | Aristotle promoted the importance of properties and objects (rather than general and particular) [Aristotle, by Frede,M] |
| Full Idea: In 'Categories' Aristotle is taking a first step in making the distinction between objects and properties central to ontology. This plays virtually no role in Plato, and was overshadowed by the distinction between general and particular. | |
| From: report of Aristotle (Categories [c.331 BCE]) by Michael Frede - Individuals in Aristotle I | |
| A reaction: Frede says he gets in a tangle because he mixes the earlier and the new views. Because we are nowadays in a total muddle about properties, I'm thinking we should go back to the earlier view! Modern commentators make him a trope theorist. |
| 11032 | Some things said 'of' a subject are not 'in' the subject [Aristotle] |
| Full Idea: Of things there are, some are said of a subject, but are not in any subject. For example, man is said of a subject, the individual man, but is not in any subject. | |
| From: Aristotle (Categories [c.331 BCE], 01a20) | |
| A reaction: See? 'Being a man' is not a property of a man! Only the properties which are 'in' the man are properties of the man. The rest are things which are said 'of' men, usually as classifications. A classification is not a property. |
| 11038 | We call them secondary 'substances' because they reveal the primary substances [Aristotle] |
| Full Idea: It is reasonable that, after the primary substances, their species and genera should be the only other things called (secondary) substances. For only they, of things predicated, reveal the primary substance. | |
| From: Aristotle (Categories [c.331 BCE], 02b29) | |
| A reaction: This is the key passage in all of Aristotle for sortal essentialists like Wiggins, especially the word 'only'. I take it that this observation is superseded by the Metaphysics. Definition is the route to substance (which involves general terms). |
| 16739 | Four species of quality: states, capacities, affects, and forms [Aristotle, by Pasnau] |
| Full Idea: In Categories 8 there are four species of qualities: States and conditions, Natural capacities and incapacities, Affective qualities or affections, and Shape and external form. | |
| From: report of Aristotle (Categories [c.331 BCE], Ch.8) by Robert Pasnau - Metaphysical Themes 1274-1671 23.5 |
| 11037 | Colour must be in an individual body, or it is not embodied [Aristotle] |
| Full Idea: Colour is in body and therefore also in an individual body; for were it not in some individual body it would not be in body at all. | |
| From: Aristotle (Categories [c.331 BCE], 02b02) | |
| A reaction: This may be just a truism, or it may be the Aristotelian commitment to universals only existing if they are instantiated. |
| 16154 | Aristotle gave up his earlier notion of individuals, because it relied on universals [Aristotle, by Frede,M] |
| Full Idea: In 'Metaphysics' Aristotle abandons the notion of an individual which he had relied on in the 'Categories', since it presupposes that there are general things, that there are universals. | |
| From: report of Aristotle (Categories [c.331 BCE]) by Michael Frede - Individuals in Aristotle Intro | |
| A reaction: Ah, very illuminating. So all the way through we have a concept of individuals, first relying on universals, and then relying on hylomorphism? I suppose a bundle theory of individuals would need universals. |
| 12351 | Genus and species are substances, because only they reveal the primary substance [Aristotle, by Wedin] |
| Full Idea: The reason Aristotle gives for calling species and genera substances is that of what is predicated only they reveal what the primary substance is. | |
| From: report of Aristotle (Categories [c.331 BCE], 02b29-37) by Michael V. Wedin - Aristotle's Theory of Substance III.6 | |
| A reaction: Thus we should not be misled into thinking that the genus and species ARE the essence. We edge our way towards the essence of an individual by subdividing its categories. |
| 1694 | Substances have no opposites, and don't come in degrees (including if the substance is a man) [Aristotle] |
| Full Idea: There is nothing contrary to substances,…. and a substance does not admit of a more and a less. If this substance is a man, it will not be more a man or less a man either than itself or than another man. | |
| From: Aristotle (Categories [c.331 BCE], 03b33) |
| 16091 | Is primary substance just an ultimate subject, or some aspect of a complex body? [Aristotle, by Gill,ML] |
| Full Idea: 'Categories' treats something's being an ultimate subject as a test for being a primary substance, but it does not treat its primary objects as complex bodies consisting of matter and form. In that case, is the composite or a feature the ultimate subject? | |
| From: report of Aristotle (Categories [c.331 BCE]) by Mary Louise Gill - Aristotle on Substance Ch.1 | |
| A reaction: Gill is trying to throw light on the difference between 'Categories' and 'Metaphysics'. Once you have hylomorphism (form-plus-matter) you have a new difficulty in explaining unity. The answer is revealed once we understand 'form'. |
| 11280 | Primary being is 'that which lies under', or 'particular substance' [Aristotle, by Politis] |
| Full Idea: In 'Categories' Aristotle argues the primary being (proté ousia) is the ultimate subject of predication (to hupokeimenon, meaning 'that which lies under'), nowadays referred to as the 'particular substance' view. | |
| From: report of Aristotle (Categories [c.331 BCE]) by Vassilis Politis - Aristotle and the Metaphysics 4.4 | |
| A reaction: Politis says that Aristotle shifts to the quite different view in 'Metaphysics', that primary being is essence, rather than mere subject of predication. |
| 11040 | A single substance can receive contrary properties [Aristotle] |
| Full Idea: It seems distinctive of substance that what is numerically one and the same is able to receive contraries. ...For example, an individual man - one and the same - becomes pale at one time and dark at another. | |
| From: Aristotle (Categories [c.331 BCE], 04a10/20) |
| 16140 | Secondary substances do have subjects, so they are not ultimate in the ontology [Aristotle, by Frede,M] |
| Full Idea: The concept of substance applies to secondary substances only with some deletions; ..it is not true that they have no subjects, and hence they are not ultimate subjects for all other elements of the ontology. | |
| From: report of Aristotle (Categories [c.331 BCE]) by Michael Frede - Title, Unity, Authenticity of the 'Categories' V | |
| A reaction: It increasingly strikes that to treat secondary substance (roughly, species) as essence is a shocking misreading of Aristotle. Frede says they are substances, because they do indeed 'underlie'. |
| 10965 | In earlier Aristotle the substances were particulars, not kinds [Aristotle, by Lawson-Tancred] |
| Full Idea: In 'Metaphysics' Aristotle changed his view, as in 'Categories' the substances, the basic realities, were particular items, notably individual men, horses, cabbages etc. | |
| From: report of Aristotle (Categories [c.331 BCE]) by Hugh Lawson-Tancred - Introductions to 'Metaphysics' p.178 | |
| A reaction: The charge is that having successfully rebelled against Plato, Aristotle gradually succumbed to his teacher's influence, and ended up with a more platonist view. For anti-platonists like myself, the 'Categories' seems to be the key text. |
| 11036 | A 'primary' substance is in each subject, with species or genera as 'secondary' substances [Aristotle] |
| Full Idea: A substance, in its most primary sense, is that which is neither said of a subject nor in a subject, e.g. the individual man or horse. The species in which things primarily called substances are, are called secondary substances, as are the genera. | |
| From: Aristotle (Categories [c.331 BCE], 02a11) | |
| A reaction: This distinction between 'primary' and 'secondary' substances is characteristic of Aristotle's earlier metaphysical view, with the later view (more unified and Platonic) in the 'Metaphysics'. |
| 8287 | Earlier Aristotle had objects as primary substances, but later he switched to substantial form [Aristotle, by Lowe] |
| Full Idea: In 'Categories' primary substances are individual concrete objects, such as a particular horse, whereas in 'Metaphysics' such things are combinations of matter and substantial form, with the latter being the primary substances. | |
| From: report of Aristotle (Categories [c.331 BCE]) by E.J. Lowe - The Possibility of Metaphysics 9.1 | |
| A reaction: Lowe claims there is no real difference. Aristotle came to think that matter was not part of primary substance, so the shift seems to be that substance was concrete, but then he decided it was abstract. Physicists will prefer 'Metaphysics'. |
| 12350 | Things are called 'substances' because they are subjects for everything else [Aristotle] |
| Full Idea: It is because the primary substances are subjects for everything else that they are called substances [ousiai] most strictly. | |
| From: Aristotle (Categories [c.331 BCE], 03a04) | |
| A reaction: This points to a rather minimal account of substance, as possibly the 'bare particular' which has no other role than to have properties. This expands in 'Metaphysics' to be matter which has form, making properties possible. |
| 11039 | A primary substance reveals a 'this', which is an individual unit [Aristotle] |
| Full Idea: Every substance seems to signify a certain 'this'. As regards the primary substances, it is indisputably true that each of them signifies a certain 'this'; for the thing revealed is individual and numerically one. | |
| From: Aristotle (Categories [c.331 BCE], 03b10) | |
| A reaction: The notion of 'primary' substance is confined to this earlier metaphysics of Aristotle. |
| 12361 | Primary substances are ontological in 'Categories', and explanatory in 'Metaphysics' [Aristotle, by Wedin] |
| Full Idea: The primacy of 'Categories' primary substances is a kind of ontological primacy, whereas the primacy of form is a kind of structural or explanatory primacy. | |
| From: report of Aristotle (Categories [c.331 BCE]) by Michael V. Wedin - Aristotle's Theory of Substance X.9 | |
| A reaction: 'Structural' and 'explanatory' sound very different, since the former sounds ontological and the latter epistemological (and more subjective). |
| 3315 | Aristotle denigrates the category of relation, but for modern absolutists self-relation is basic [Benardete,JA on Aristotle] |
| Full Idea: Aristotle denigrates the whole category of relations, but modern logical absolutists single out self-relation (in the mode of identity) as metaphysically privileged. | |
| From: comment on Aristotle (Categories [c.331 BCE]) by José A. Benardete - Metaphysics: the logical approach Ch.8 | |
| A reaction: I think this refers to Plantinga and Merrihew Adams, who make identity-with-itself the basic component of individual existences. |
| 5183 | Only tautologies can be certain; other propositions can only be probable [Ayer] |
| Full Idea: No proposition, other than a tautology, can possibly be anything more than a probable hypothesis. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.1) | |
| A reaction: A nice clear empiricist rejection of all attempts to assert necessary truths about nature. This also seems to be a rejection of empiricist foundationalism. A problem case seems to be introspective observations, which seem irrefutable and obvious. |
| 6525 | Logical positivists could never give the sense-data equivalent of 'there is a table next door' [Robinson,H on Ayer] |
| Full Idea: Logical positivist phenomenalism has few supporters these days; ..no one ever seemed clear what the sense-datum equivalent of 'there is a table in the next room' could be. | |
| From: comment on A.J. Ayer (Language,Truth and Logic [1936]) by Howard Robinson - Perception IX.4 | |
| A reaction: But do the critics know what they mean by 'there is a table in the next room'? Does it just mean 'I am hoping there is'? You can't refer to the table in the next room without sticking your ontological neck out - and that is 'best explanation'. |
| 5170 | Material things are constructions from actual and possible occurrences of sense-contents [Ayer] |
| Full Idea: The existence of a material thing is defined in terms of the actual and possible occurrence of the sense-contents which constitute it as a logical construction. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.7) | |
| A reaction: Obviously we need 'possible' experiences so that unperceived trees can still exist, but it is a can of worms. Is speculation about a possible world an account of possible experiences? Realists want to know WHY we think certain experiences are possible. |
| 5198 | We could verify 'a thing can't be in two places at once' by destroying one of the things [Ierubino on Ayer] |
| Full Idea: It is possible to challenge the proposition 'a material thing cannot be in two places at once' empirically; if you destroy one object, the other should also instantly be destroyed if they are a single thing. | |
| From: comment on A.J. Ayer (Language,Truth and Logic [1936], Ch.2) by Virgil Ierubino - works | |
| A reaction: This leaves us having to decide whether the proposition is metaphysically necessary, or is empirical, or is tautological. This idea inclines me towards the view that it is empirical. Imagine two 'separate' objects which responded identically to stimuli. |
| 2619 | Whether geometry can be applied to reality is an empirical question outside of geometry [Ayer] |
| Full Idea: Whether a geometry can be applied to the actual physical world or not, is an empirical question which falls outside the scope of the geometry itself. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.4) | |
| A reaction: This is a key objection to rationalism by empiricists. You may say that geometry applies to your car, but your car may have been pulverised while you were talking. Why, though, did Einstein find non-Euclidean geometry so useful? |
| 5197 | By changing definitions we could make 'a thing can't be in two places at once' a contradiction [Ayer] |
| Full Idea: The proposition that 'a material thing cannot be in two places at once' is not empirical at all, but linguistic; ..we could so alter our definitions that the proposition came to express a self-contradiction instead of a necessary truth. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.2) | |
| A reaction: This seems a striking anticipation of Quine's famous challenge to the analytic/synthetic distinction. |
| 5204 | To say that a proposition is true a priori is to say that it is a tautology [Ayer] |
| Full Idea: To say that a proposition is true a priori is to say that it is a tautology. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.4) | |
| A reaction: This is Ayer's splendidly clearcut anti-rationalism. However, one might concede that one cannot know a priori about remote possible worlds (though I'm not so sure), but still claim a priori extrapolations from our current experiences. |
| 6524 | Positivists prefer sense-data to objects, because the vocabulary covers both illusions and perceptions [Ayer, by Robinson,H] |
| Full Idea: Positivists prefer the sense-datum vocabulary because it is more inclusive than physical object vocabulary; it can report after-images, hallucinations, illusions and bodily sensations, as well as veridical perceptions. | |
| From: report of A.J. Ayer (Language,Truth and Logic [1936]) by Howard Robinson - Perception IX.4 | |
| A reaction: The assumption of this is that illusions and perceptions are frequently indistinguishable, but that is just nonsense. Illusions usually appeal to one sense only, when you are ill, and in an unclear way. Sensible people know objects when they see them. |
| 5193 | Causal and representative theories of perception are wrong as they refer to unobservables [Ayer] |
| Full Idea: The fact that all causal and representative theories of perception treat material things as if they were unobservable entities entitles us to rule them out a priori. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.2) | |
| A reaction: It seems to me that we can accept a causal/representative account of perception if we think of it in terms of 'best explanation' rather than observables. Explanation requires speculation, which logical positivists can't cope with. |
| 5200 | The main claim of rationalism is that thought is an independent source of knowledge [Ayer] |
| Full Idea: The fundamental tenet of rationalism is that thought is an independent source of knowledge. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.4) | |
| A reaction: Presumably one should add that thought gives synthetic knowledge. Thought is also an experience, so empiricists will always acknowledge that we could have some knowledge (of thought) by thought alone. |
| 4729 | Empiricism lacked a decent account of the a priori, until Ayer said it was entirely analytic [O'Grady on Ayer] |
| Full Idea: Ayer's gives an account of the a priori (as analytic) that readily meshes with empiricism, and empiricism had long been lacking an adequate account of the a priori | |
| From: comment on A.J. Ayer (Language,Truth and Logic [1936]) by Paul O'Grady - Relativism Ch.4 | |
| A reaction: Ayer's logical positivist view was based on Hume's 'relations of ideas', as opposed to 'matters of fact'. Personally I see no reason why some facts about reality shouldn't be self-evident to thought, just as others are self-evident to the senses. |
| 5180 | All propositions (especially 'metaphysics') must begin with the senses [Ayer] |
| Full Idea: One way to attack a metaphysician would be to enquire from what premises his propositions were deduced. Must he not begin, as other men do, with the evidence of his senses? | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.1) | |
| A reaction: This simple idea is the core of empiricism. This is a heavily criticised doctrine, but you must start somewhere. Hume and Russell agreed. Don't forget, though, that Descartes's first move is to reject the senses as untrustworthy. |
| 5169 | My empiricism logically distinguishes analytic and synthetic propositions, and metaphysical verbiage [Ayer] |
| Full Idea: The empiricist doctrine to which we are committed is a logical doctrine concerning the distinction between analytic propositions, synthetic propositions, and metaphysical verbiage. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.7) | |
| A reaction: This is the tough logical positivist version of empiricism. The whole project stumbles on the relationship between a synthetic proposition and its verifying experiences. How close? What of wild speculations? The analytic part is interesting, though. |
| 5185 | It is further sense-experience which informs us of the mistakes that arise out of sense-experience [Ayer] |
| Full Idea: It is further sense-experience which informs us of the mistakes that arise out of sense-experience. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.1) | |
| A reaction: This is a wonderfull plain-spoken challenge to anyone who thinks they can demonstrate facts a priori about reality. 'I see this object in two places at once'? 'This object appears to be both red and green'? |
| 5199 | Empiricism, it is said, cannot account for our knowledge of necessary truths [Ayer] |
| Full Idea: The objection which is commonly brought against empiricism is that it is impossible on empiricist principles to account for our knowledge of necessary truths. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.4) | |
| A reaction: This criticism goes back at least to Leibniz. Ayer's distinctive contribution to empiricism (with help) is to emphasise that we can only know necessities if they are tautologies. Hume always challenged our knowledge of natural necessities. |
| 5190 | The induction problem is to prove generalisations about the future based on the past [Ayer] |
| Full Idea: The problem of induction is (roughly) finding a way to prove that certain empirical generalisations which are derived from past experience will hold good also in the future. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.2) | |
| A reaction: This doesn't seem to be the only problem. It seems self-evident (since Hume) that you cannot use deductive reasoning to prove that the future will be like the past. In fact, we should obviously be cautious, as things could easily change. |
| 5191 | We can't use the uniformity of nature to prove induction, as that would be circular [Ayer] |
| Full Idea: It is often said that we can justify induction by invoking the uniformity of nature, but that principle merely states (in a misleading fashion) the assumption that past experience is a reliable guide to the future. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.2) | |
| A reaction: That is correct, but it seems to me that if you take the uniformity of nature as a provisional unproven axiom, then induction is an account of how rational creatures cope with the situation. If nature ceases to be uniform, our reason cannot cope. |
| 5177 | Other minds are 'metaphysical' objects, because I can never observe their experiences [Ayer] |
| Full Idea: On the view that we are discussing, I must regard other people as metaphysical objects; for it is assumed that their experiences are completely inaccessible to my observation. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.7) | |
| A reaction: 'Metaphysical' is here a dirty word. This is the strictly empirical view of other minds, which pushes Ayer towards behaviourism on this subject. He should have asked about the 'best explanation' of the behaviour of others'. |
| 5178 | A conscious object is by definition one that behaves in a certain way, so behaviour proves consciousness [Ayer] |
| Full Idea: If I know that an object behaves in every way as a conscious being must, by definition, behave, then I know that it is really conscious. This is an analytical proposition. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.7) | |
| A reaction: This treats the Turing test as proof of consciousness, and is open to all the usual objections to behaviourism. To say behaviour IS consciousness is ridiculous. It just counts as evidence. Presumably Ayer would later have become a functionalist. |
| 5172 | If the self is meaningful, it must be constructed from sense-experiences [Ayer] |
| Full Idea: The self, if it is not to be treated as a metaphysical entity, must be held to be a logical construction out of sense-experiences. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.7) | |
| A reaction: It is striking how people differ in their reports when they try to see the self by introspection. The self could be beyond sense-experience, and yet still be the best explanation of what we actually DO experience. It is a 'transcendental sensation'? |
| 5173 | Two experiences belong to one self if their contents belong with one body [Ayer] |
| Full Idea: For any two sense-experiences to belong to the sense-history of the same self it is necessary and sufficient that they should contain organic sense-contents which are elements of the same body. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.7) | |
| A reaction: This makes more sense if you are a realist about organic bodies, but less sense if (like Ayer) you define the body in terms of sense-experiences. It is a stab at what is now called 'animalism', but needs an account of brain transplant thought-experiments. |
| 5176 | Empiricists can define personal identity as bodily identity, which consists of sense-contents [Ayer] |
| Full Idea: We have solved Hume's problem by defining personal identity in terms of bodily identity, and bodily identity is to be defined in terms of the resemblance and continuity of sense-contents. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.7) | |
| A reaction: This is a phenomenalist account of personal identity, so it has no independent account of the body apart from the contents of the mind. Personally I think we must distinguish 'central' mental events from 'peripheral' ones. |
| 6028 | Bodies interact with other bodies, and cuts cause pain, and shame causes blushing, so the soul is a body [Cleanthes, by Nemesius] |
| Full Idea: Cleanthes says no incorporeal interacts with a body, but one body interacts with another body; the soul interacts with the body when it is sick and being cut, and the body feels shame and fear, and turns red or pale, so the soul is a body. | |
| From: report of Cleanthes (fragments/reports [c.270 BCE]) by Nemesius - De Natura Hominis 78,7 | |
| A reaction: This is precisely the interaction problem with dualism, or, as we might now say, the problem of mental causation. The standard Stoic view is that the soul is a sort of rarefied fire, which disperses at death. |
| 5171 | The supposed 'gulf' between mind and matter is based on the senseless concept of 'substances' [Ayer] |
| Full Idea: The problems of bridging the 'gulf' between mind and matter, in knowledge or in action, are all fictitious problems arising out of the senseless metaphysical conception of mind and matter as 'substances'. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.7) | |
| A reaction: He is presumably implying that there is only one 'substance', the stuff of physics, thus voting for Spinoza's dual aspect theory. There could still be a 'gulf', between incommensurable properties, or untranslatable levels of description. |
| 20831 | The soul suffers when the body hurts, creates redness from shame, and pallor from fear [Cleanthes] |
| Full Idea: Nothing incorporeal shares an experience with a body …but the soul suffers with the body when it is ill and when it is cut, and the body suffers with the soul - when the soul is ashamed the body turns red, and pale when the soul is frightened. | |
| From: Cleanthes (fragments/reports [c.270 BCE]), quoted by Nemesius - De Natura Hominis 2 | |
| A reaction: Aha - my favourite example of the corporeal nature of the mind - blushing! It is the conscious content of the thought which brings blood to the cheeks. |
| 5181 | A sentence is factually significant to someone if they know how to verify its proposition [Ayer] |
| Full Idea: A sentence is factually significant to any given person, if, and only if, he knows how to verify the proposition which it purports to express. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.1) | |
| A reaction: 'I can't verify it, but I know a bloke who can'? 'If only I could think of a way to verify x'? 'This is unverifiable, but it is the only remaining possibility'? 'X is unverifiable, but it would nice if it was true'? Etc. |
| 5184 | Factual propositions imply (in conjunction with a few other premises) possible experiences [Ayer] |
| Full Idea: The mark of a genuinely factual proposition is that some experiential propositions can be deduced from it in conjunction with certain other premises without being deducible from those premises alone. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.1) | |
| A reaction: I.Berlin showed that any statement S could pass this test, because if you assert 'S' and 'If S then O', these two statements entail O, which could be some random observation. Verificationism kept meeting problems of this kind. |
| 5186 | Tautologies and empirical hypotheses form the entire class of significant propositions [Ayer] |
| Full Idea: Tautologies and empirical hypotheses form the entire class of significant propositions. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.1) | |
| A reaction: This appears to be false. Possibly the problem is that Ayer takes the whole proposition to be the unit of meaning, but actually meaninfulness only requires that we build up a claim about a possible world from semantic units. Blue bees live on square suns. |
| 12349 | Only what can be said of many things is a predicable [Aristotle, by Wedin] |
| Full Idea: Aristotle reminds us that nothing is to count as predicable that cannot be said-of many things. | |
| From: report of Aristotle (Categories [c.331 BCE]) by Michael V. Wedin - Aristotle's Theory of Substance III.1 | |
| A reaction: Thus there wouldn't be any predicates if there were not universals. Could we have proper names for individual qualities (tropes), in the way that we have them for individual objects? |
| 11837 | Some predicates signify qualification of a substance, others the substance itself [Aristotle] |
| Full Idea: 'White' signifies nothing but a qualification, whereas the species ('man') and the genus ('animal') mark off the qualification of substance - they signify substance of a certain qualification. | |
| From: Aristotle (Categories [c.331 BCE], 03b18) | |
| A reaction: This is making a fundamental distinction between two different types of predication. I would describe them as one attributing a real property, and the other attributing a category (as a result of the properties). I don't think 'substance' helps here. |
| 5205 | Moral intuition is worthless if there is no criterion to decide between intuitions [Ayer] |
| Full Idea: Unless it is possible to provide some criterion by which one may decide between conflicting intuitions, a mere appeal to intuition is worthless as a test of a proposition's validity. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.6) | |
| A reaction: It is a bit much to expect a 'proof' of its 'validity'! If moral judgements are reflected in consequences, then reliable intuitions (i.e. wisdom) could be demonstrated by getting it right (for happiness, or flourishing). |
| 23725 | Ayer defends the emotivist version of expressivism [Ayer, by Smith,M] |
| Full Idea: Ayer defends emotivism, which is his own favoured form of expressivism. | |
| From: report of A.J. Ayer (Language,Truth and Logic [1936], Ch.6) by Michael Smith - The Moral Problem 2.1 | |
| A reaction: A helpful distinction of terminology. Expressivism is the broad theory, and emotivism is a sub-type, saying that it is emotions which are expressed. The alternative (such as Prescriptivism) is to express pro- and con- attitudes. |
| 5206 | To say an act is wrong makes no further statement about it, but merely expresses disapproval [Ayer] |
| Full Idea: In adding 'You acted wrongly in…' to 'you stole my money' I am not making any further statement about it; I am simply evincing my moral disapproval of it. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.6) | |
| A reaction: A basic claim of emotivism. Perhaps an understandable response to (e.g.) Kantian claims that we have duties, but to no one in particular. Most people mean by moral criticism that there will be long-term bad consequences, or virtue is lacking. |
| 11043 | It is not possible for fire to be cold or snow black [Aristotle] |
| Full Idea: It is not possible for fire to be cold or snow black. | |
| From: Aristotle (Categories [c.331 BCE], 12b01) |
| 1696 | Change goes from possession to loss (as in baldness), but not the other way round [Aristotle] |
| Full Idea: Change occurs from possession to privation, but from privation to possession is impossible; one who has gone blind does not recover sight nor does a bald man regain his hair nor does a toothless man grow new ones. | |
| From: Aristotle (Categories [c.331 BCE], 13a35) | |
| A reaction: Although this seems like an insight into entropy, it isn't an accurate observation, since trees lose their leaves, and then regain them in spring. Maybe somewhere men regrow their hair each spring. |
| 5208 | A person with non-empirical attributes is unintelligible. [Ayer] |
| Full Idea: The notion of a person whose essential attributes are non-empirical is not an intelligible notion at all. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.6) | |
| A reaction: Non-empirical and non-causal are not quite the same thing. A being which never had any effects is a bizarre, and probably pointless, fantasy. A being which affected our world (through ideas, say) but is unobservable is a perfectly good theory. |
| 5187 | When we ascribe an attribute to a thing, we covertly assert that it exists [Ayer] |
| Full Idea: When we ascribe an attribute to a thing, we covertly assert that it exists. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.1) | |
| A reaction: This is an unsurprising endorsement from logical positivism that Kant's claim that the ontological argument is probably tautological is correct. We could of course say "Imagine a non-existent being with dirty toenails". |
| 5993 | The ascending scale of living creatures requires a perfect being [Cleanthes, by Tieleman] |
| Full Idea: Cleanthes tried to prove the existence of God, arguing that the ascending scale of living creatures requires there to be a perfect being. | |
| From: report of Cleanthes (fragments/reports [c.270 BCE]) by Teun L. Tieleman - Cleanthes | |
| A reaction: Not a very good argument. Even if you accept its basic claim, it is not clear what has to exist. A perfect tree? If the being transcends the physical (in order to achieve perfection), does it cease to be a 'being'? |
| 5207 | If theism is non-sensical, then so is atheism. [Ayer] |
| Full Idea: If the assertion that there is a god is non-sensical, then the atheist's assertion that there is no god is equally non-sensical. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.6) | |
| A reaction: Ayer urgently needs the concept of 'best explanation'. If we observe only footprints, we infer creatures; if there are no footprints, lack of creatures looks like a good theory. The design argument is perfectly meaningful. |
| 5209 | The 'truths' expressed by theists are not literally significant [Ayer] |
| Full Idea: There cannot be any transcendent truths of religion, for the sentences which the theist uses to express such 'truths' are not literally significant. | |
| From: A.J. Ayer (Language,Truth and Logic [1936], Ch.6) | |
| A reaction: Ayer claims that only tautologies or empirically verifiable statements have literal significance. I say speculations, wild theories and fantasies are perfectly meaningful. Nevertheless, the words of many hymns and prayers look like empty rhetoric. |