61 ideas
| 2352 | The job of the philosopher is to distinguish facts about the world from conventions [Putnam] |
| Full Idea: It is the job of the philosopher to distinguish what is fact and what is convention in our theorising about the world. | |
| From: Hilary Putnam (Representation and Reality [1988], §7 p.112) | |
| A reaction: This may well be the entire truth about philosophy. It begins with the Nomos-Physis debate in ancient Athens, and it turns out to be the key issue in almost every area of metaphysics, epistemology, aesthetics and morality. |
| 1887 | You cannot divide anything into many parts, because after the first division you are no longer dividing the original [Sext.Empiricus] |
| Full Idea: You cannot divide anything (such as the decad) into many parts, because as soon as you separate the first part, you are no longer dividing the original. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], II.215) |
| 1885 | Proof moves from agreed premises to a non-evident inference [Sext.Empiricus] |
| Full Idea: Dogmatists define proof as "an argument which, by means of agreed premises, reveals by way of deduction a nonevident inference". | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], II.135) |
| 2345 | Semantic notions do not occur in Tarski's definitions, but assessing their correctness involves translation [Putnam] |
| Full Idea: Although no semantic notions are used in Tarski's truth definitions themselves, they are used in deciding when such a definition is correct, namely the notion of translation. | |
| From: Hilary Putnam (Representation and Reality [1988], §4 p.66) |
| 2347 | Asserting the truth of an indexical statement is not the same as uttering the statement [Putnam] |
| Full Idea: If you say "I am going to drive this car", and I say "That's true", that is very different from my saying "I am going to drive this car". | |
| From: Hilary Putnam (Representation and Reality [1988], §4 p.68) |
| 12196 | A valid hypothetical syllogism is 'that which does not begin with a truth and end with a falsehood' [Sext.Empiricus] |
| Full Idea: Philo (of Megara) says that a valid hypothetical syllogism is 'that which does not begin with a truth and end with a falsehood,' as for instance the syllogism 'If it is day, I converse,' when in fact it is day and I am conversing. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], II.110) | |
| A reaction: Russell endorses this, and Rumfitt quotes it as the classic case of denying that there is any modal aspect (such as 'logical necessity') involved in logical consequence. He labels it 'material or Philonian consequence'. |
| 1902 | Since Socrates either died when he was alive (a contradiction) or died when he was dead (meaningless), he didn't die [Sext.Empiricus] |
| Full Idea: If Socrates died, he died either when he lived or when he died; so he was either dead when he was alive, or he was twice dead when he was dead. So he didn't die. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.111) | |
| A reaction: One of my favourites. Of all the mysteries facing us, the one that boggles me most is how anything can happen in the 'present' moment, if the present is just the overlap point between past and future. |
| 2349 | Realists believe truth is correspondence, independent of humans, is bivalent, and is unique [Putnam] |
| Full Idea: Metaphysical realism about truth is a bundle of ideas: that it is a matter of Correspondence, that it exhibits Independence (of humans), Bivalence, and Uniqueness (there is only one ultimate truth). | |
| From: Hilary Putnam (Representation and Reality [1988], §7 p.107) |
| 2351 | Aristotle says an object (e.g. a lamp) has identity if its parts stay together when it is moved [Putnam] |
| Full Idea: The parts of a lamp stay together when it is moved (which is one of Aristotle's criteria for objecthood). | |
| From: Hilary Putnam (Representation and Reality [1988], §7 p.110) | |
| A reaction: Metaphysics 1052a26 (just after the cross-reference) says a thing may be unified 'if its movement is single'. |
| 1889 | If an argument has an absurd conclusion, we should not assent to the absurdity, but avoid the absurd argument [Sext.Empiricus] |
| Full Idea: If an argument leads to confessedly absurd conclusions, we should not assent to the absurdity just because of the argument, but avoid the argument because of the absurdity. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], II.252) | |
| A reaction: cf. G.E.Moore. Denying that you have a hand seems to be an absurdity, but I'm not sure if I can give a criterion for absurdity in such a case. One person's modus ponens is another person's modus tollens. |
| 1871 | Whether honey is essentially sweet may be doubted, as it is a matter of judgement rather than appearance [Sext.Empiricus] |
| Full Idea: Honey appears to sceptics to be sweet, but whether it is also sweet in its essence is for us a matter of doubt, since this is not an appearance but a judgement. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], I.20) |
| 1883 | How can the intellect know if sensation is reliable if it doesn't directly see external objects? [Sext.Empiricus] |
| Full Idea: Just as you can't know if a portrait of Socrates is good without seeing the man, so when the intellect gazes on sensations but not the external objects it cannot know whether they are similar. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], II.75) |
| 1890 | We distinguish ambiguities by seeing what is useful [Sext.Empiricus] |
| Full Idea: It is the experience of what is useful in each affair that brings about the distinguishing of ambiguities. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], II.258) |
| 1870 | The basis of scepticism is the claim that every proposition has an equal opposing proposition [Sext.Empiricus] |
| Full Idea: The main basic principle of the sceptic system is that of opposing to every proposition an equal proposition. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], I.12) |
| 1882 | The necks of doves appear different in colour depending on the angle of viewing [Sext.Empiricus] |
| Full Idea: The necks of doves appear different in hue according to the differences in the angle of inclination. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], I.120) |
| 1881 | The same oar seems bent in water and straight when out of it [Sext.Empiricus] |
| Full Idea: The same oar seems bent when in the water but straight when out of the water. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], I.119) |
| 1872 | The same tower appears round from a distance, but square close at hand [Sext.Empiricus] |
| Full Idea: The same tower appears round from a distance, but square close at hand. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], I.32) |
| 1873 | If we press the side of an eyeball, objects appear a different shape [Sext.Empiricus] |
| Full Idea: When we press the eyeball at one side the forms, figures and sizes of the objects appear oblong and narrow. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], I.47) |
| 1874 | How can we judge between our impressions and those of other animals, when we ourselves are involved? [Sext.Empiricus] |
| Full Idea: We cannot judge between our own impressions and those of other animals, because we ourselves are involved in the dispute. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], I.59) |
| 1878 | Water that seems lukewarm can seem very hot on inflamed skin [Sext.Empiricus] |
| Full Idea: The same water which seems very hot when poured on inflamed spots seems lukewarm to us. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], I.101) |
| 1880 | Some actions seem shameful when sober but not when drunk [Sext.Empiricus] |
| Full Idea: Actions which seem shameful to us when sober do not seem shameful when drunk. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], I.109) |
| 1877 | If we had no hearing or sight, we would assume no sound or sight exists, so there may be unsensed qualities [Sext.Empiricus] |
| Full Idea: A man with touch, taste and smell, but no hearing or sight, will assume nothing audible or visible exists, so maybe an apple has qualities which we have no senses to perceive. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], I.96) |
| 1879 | Sickness is perfectly natural to the sick, so their natural perceptions should carry some weight [Sext.Empiricus] |
| Full Idea: Health is natural for the healthy but unnatural for the sick, and sickness is unnatural for the healthy but natural for the sick, so we must give credence to the natural perceptions of the sick. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], I.103) |
| 1876 | If we enjoy different things, presumably we receive different impressions [Sext.Empiricus] |
| Full Idea: The enjoyment of different things is an indication that we get varying impressions from the underlying objects. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], I.80) |
| 1910 | With us it is shameful for men to wear earrings, but among Syrians it is considered noble [Sext.Empiricus] |
| Full Idea: It is a shameful thing with us for men to wear earrings, but among some of the barbarians, such as the Syrians, it is a token of nobility. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.203) |
| 1911 | Even if all known nations agree on a practice, there may be unknown nations which disagree [Sext.Empiricus] |
| Full Idea: Even among practices on which all known cultures are agreed, disagreement about them may possibly exist amongst some of the nations which are unknown to us. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.234) |
| 1886 | If you don't view every particular, you may miss the one which disproves your universal induction [Sext.Empiricus] |
| Full Idea: Induction cannot establish the universal by means of the particular, since limited particulars may omit crucial examples which disprove the universal, and infinite particulars are impossible to know. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], II.204) |
| 2331 | Functionalism says robots and people are the same at one level of abstraction [Putnam] |
| Full Idea: My "functionalism" insisted that a robot, a human being, a silicon creature and a disembodied spirit could all work much the same way when described at the relevant level of abstraction, and it is wrong to think the essence of mind is hardware. | |
| From: Hilary Putnam (Representation and Reality [1988], Int p.xii) | |
| A reaction: This is the key point about the theory - that it is an abstract theory of mind, saying nothing about substances. It drew, however, some misguided criticisms suggesting silly implementations. |
| 2071 | If concepts have external meaning, computational states won't explain psychology [Putnam] |
| Full Idea: Computational models of the brain/mind will not suffice for cognitive psychology. We cannot individuate concepts and beliefs without reference to the environment. Meanings aren't "in the head". | |
| From: Hilary Putnam (Representation and Reality [1988], p.73) | |
| A reaction: Mr Functionalism quits! |
| 2332 | Functionalism can't explain reference and truth, which are needed for logic [Putnam] |
| Full Idea: Functionalism has as much trouble with physical accounts of reference as of meaning. Reference is the main tool used in formal theories of truth. But 'truth' isn't folk psychology, it is central to logic, which everyone wants. | |
| From: Hilary Putnam (Representation and Reality [1988], Int p.xiv) | |
| A reaction: All logic is defined in terms of truth and falsehood resulting from reasoning, but it could be that 'true' and 'false' have no more content that 1 and 0 in binary electronics. They are distinct, but empty. |
| 2348 | Is there just one computational state for each specific belief? [Putnam] |
| Full Idea: The idea that there is one computational state that every being who believes that there are lots of cats in the neighbourhood is in must be false. | |
| From: Hilary Putnam (Representation and Reality [1988], §5 p.84) | |
| A reaction: It is tempting to say that the mental states of such people must have SOMETHING in common, until you realise that all you can specify is that all their states are about cats. |
| 2344 | If we are going to eliminate folk psychology, we must also eliminate folk logic [Putnam] |
| Full Idea: Why don't the eliminationists speak of "folk logic" as well as "folk psychology"? | |
| From: Hilary Putnam (Representation and Reality [1988], §4 p.60) | |
| A reaction: I think Putnam considers that if you can prove 'truth' to be a necessary feature of mental life, that connects mind and world, but marking a sentence as 'T' doesn't make any connections. |
| 2074 | Can we give a scientific, computational account of folk psychology? [Putnam] |
| Full Idea: The desire that grips Fodor, as it once gripped me, is the desire to make belief-desire psychology "scientific" by simply identifying it outright with computational psychology. | |
| From: Hilary Putnam (Representation and Reality [1988], p.7) | |
| A reaction: An "outright" identification looks very implausible. It seems that we should accept that belief-desire psychology is a very good guide to normal brain events, but a bad guide to unusual brain events. See Ideas 2987 and 7519. |
| 1884 | If we utter three steps of a logical argument, they never exist together [Sext.Empiricus] |
| Full Idea: If we say "If day exists, lights exists", and then "day exists", and then "light exists", then parts of the judgement never exist together, and so the whole judgement will have no real existence. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], II.109) |
| 2343 | Reference may be different while mental representation is the same [Putnam] |
| Full Idea: The 'mental representations' of Earth speakers and Twin Earth speakers were not in any way different; the reference was different because the substances were different. Reference is fixed by the environment itself. | |
| From: Hilary Putnam (Representation and Reality [1988], §2 p.32) | |
| A reaction: There seems to be an elementary distinction here between what you think you are referring to, and what you are in fact referring to. "That man is the Prince of Wales" (pointing at the butler). |
| 2346 | Meaning and translation (which are needed to define truth) both presuppose the notion of reference [Putnam] |
| Full Idea: The notion of meaning, and hence of translation (needed to define truth), presupposes the notion of reference. | |
| From: Hilary Putnam (Representation and Reality [1988], §4 p.67) | |
| A reaction: It is plausible to see reference as the fundamental notion of language. With no anchors in reality, language would be 'private', in LW's sense. |
| 2354 | "Meaning is use" is not a definition of meaning [Putnam] |
| Full Idea: "Meaning is use" is not a definition of meaning. | |
| From: Hilary Putnam (Representation and Reality [1988], §7 p.119) | |
| A reaction: I agree. It probably fails to define meaning because it is false. A corkscrew is not the action of opening a wine bottle. |
| 2336 | Holism seems to make fixed definition more or less impossible [Putnam] |
| Full Idea: Holism immediately suggests that most terms cannot be defined, at least not in a way that is fixed once and for all. | |
| From: Hilary Putnam (Representation and Reality [1988], §1 p.09) | |
| A reaction: Perhaps there exists a single perfect definition for each holistic system, only graspable by a transcendent intellect. Or why can't there be a matching holistic system of definitions? |
| 2334 | Meaning holism tried to show that you can't get fixed meanings built out of observation terms [Putnam] |
| Full Idea: The doctrine of Quine called "meaning holism" offered arguments refuting logical positivist attempts to show that every term we can understand can be defined using a limited group of "observation terms". | |
| From: Hilary Putnam (Representation and Reality [1988], §1 p.08) | |
| A reaction: To seems a rather large jump from saying that sentences come in groups to full-blown 'holism' (involving every sentence). |
| 2335 | Understanding a sentence involves background knowledge and can't be done in isolation [Putnam] |
| Full Idea: If I say "Hawks fly", I do not intend my hearer to deduce that a hawk with a broken wing will fly. What we expect depends on the whole network of belief. Language describes experience as a network, not sentence by sentence. | |
| From: Hilary Putnam (Representation and Reality [1988], §1 p.09) | |
| A reaction: The shortcut through this is 'exactly what did you mean when you said "Hawks fly"?'. That is, get me closer to your proposition. |
| 2340 | We should separate how the reference of 'gold' is fixed from its conceptual content [Putnam] |
| Full Idea: The effect of my account, as of Kripke's, is to separate the question of how the reference of terms such as 'gold' is fixed from the question of their conceptual content. | |
| From: Hilary Putnam (Representation and Reality [1988], §2 p.38) | |
| A reaction: Too simple. 'Gold' isn't a proper name, like 'Hilary', which needs no more content than a serial number. Baptising a gold sample needs much more information than baptising a person. |
| 2341 | Like names, natural kind terms have their meaning fixed by extension and reference [Putnam] |
| Full Idea: It seems that the dominant "component" of natural kind words is the extension. The referential factor does almost all the work, and natural kind terms resemble names. | |
| From: Hilary Putnam (Representation and Reality [1988], §3 p.49) | |
| A reaction: My concept of 'tiger' does not mainly consist of the tigers. Does the concept contract as the tiger population dwindles? Prototypes, exemplars etc. See 'Concepts' |
| 2339 | Aristotle implies that we have the complete concepts of a language in our heads, but we don't [Putnam] |
| Full Idea: What is wrong with the Aristotelian picture (of meaning and reference based on concepts) is that it suggest that everything that is necessary for the use of language is stored in each individual mind, but no individual language works this way. | |
| From: Hilary Putnam (Representation and Reality [1988], §2 p.25) | |
| A reaction: Languages must partly work that way. You can't talk without a conceptual storehouse. In a small society I would expect every adult to know the full vocabulary. |
| 2338 | Reference (say to 'elms') is a social phenomenon which we can leave to experts [Putnam] |
| Full Idea: Reference is a social phenomenon. Individual speakers do not have to know how to distinguish robins, or elms, or aluminium. They can always rely on experts to do this for them. | |
| From: Hilary Putnam (Representation and Reality [1988], §2 p.22) | |
| A reaction: It can't just be a social phenomenon. The experts don't just enquire about standard usage, or defer to Hilary Putnam. |
| 2342 | "Water" is a natural kind term, but "H2O" is a description [Putnam] |
| Full Idea: "Water" functions as a natural kind term, but "H2O" is a description, synonymous with an account of its atoms. | |
| From: Hilary Putnam (Representation and Reality [1988], §3 p.50) |
| 1894 | Some say that causes are physical, some say not [Sext.Empiricus] |
| Full Idea: Some affirm cause to be corporeal, some incorporeal. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.14) |
| 1897 | Knowing an effect results from a cause means knowing that the cause belongs with the effect, which is circular [Sext.Empiricus] |
| Full Idea: To know an effect belongs to a cause, we must also know that that cause belongs to that effect, and this is circular. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.21) |
| 1898 | Cause can't exist before effect, or exist at the same time, so it doesn't exist [Sext.Empiricus] |
| Full Idea: If cause neither subsists before its effect, nor subsists along with it, nor does the effect precede the cause, it would seem that it has no substantial existence at all. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.27) |
| 1896 | If there were no causes then everything would have been randomly produced by everything [Sext.Empiricus] |
| Full Idea: If causes were non-existent everything would have been produced by everything, and at random. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.18) |
| 1895 | Causes are either equal to the effect, or they link equally with other causes, or they contribute slightly [Sext.Empiricus] |
| Full Idea: The majority say causes are immediate (when they are directly proportional to effects), or associate (making an equal contribution to effects), or cooperant (making a slight contribution). | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.15) |
| 1900 | If time and place are infinitely divided, it becomes impossible for movement ever to begin [Sext.Empiricus] |
| Full Idea: If bodies, and the places and times when they are said to move, are divided into infinity, motion will not occur, it being impossible to find anything which will initiate the first movement. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.76) |
| 1901 | If all atoms, times and places are the same, everything should move with equal velocity [Sext.Empiricus] |
| Full Idea: If objects are reducible to atoms, and each thing passes in an atomic time with its own first atom into an atomic point of space, then all moving things are of equal velocity. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.77) |
| 1899 | Does the original self-mover push itself from behind, or pull itself from in front? [Sext.Empiricus] |
| Full Idea: Self-movement must move in some particular direction, but if it pushes it will be behind itself, and if it pulls it will be in front of itself. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.68) | |
| A reaction: This is the same as Aquinas's First Way of proving God's existence. |
| 1903 | If motion and rest are abolished, so is time [Sext.Empiricus] |
| Full Idea: Since time does not seem to subsist without motion or even rest, if motion is abolished, and likewise rest, time is abolished. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.141) |
| 1904 | Time must be unlimited, but past and present can't be non-existent, and can't be now, so time does not exist [Sext.Empiricus] |
| Full Idea: There can't be a time when there was no time, so time is not limited; but unlimited time means past and present are non-existent (so time is limited to the present), or they exist (which means they are present). Time does not exist. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.142) |
| 1905 | How can time be divisible if we can't compare one length of time with another? [Sext.Empiricus] |
| Full Idea: Time is clearly divisible (into past, present and future), but it can't be, because a divisible thing is measured by some part of itself (divisions of length), but the two parts must coincide to make the measurement (e.g. present must coincide with past). | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.143) |
| 1891 | How can we agree on the concept of God, unless we agree on his substance or form or place? [Sext.Empiricus] |
| Full Idea: How shall we be able to reach a conception of God when we have no agreement about his substance or his form or his place of abode? | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.3) |
| 1892 | The existence of God can't be self-evident or everyone would have agreed on it, so it needs demonstration [Sext.Empiricus] |
| Full Idea: The existence of God is not pre-evident, for if it was the dogmatists would have agreed about it, whereas their disagreements show it is non-evident, and in need of demonstration. | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.6) |
| 16713 | Philosophers are the forefathers of heretics [Tertullian] |
| Full Idea: Philosophers are the forefathers of heretics. | |
| From: Tertullian (works [c.200]), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 20.2 |
| 6610 | I believe because it is absurd [Tertullian] |
| Full Idea: I believe because it is absurd ('Credo quia absurdum est'). | |
| From: Tertullian (works [c.200]), quoted by Robert Fogelin - Walking the Tightrope of Reason n4.2 | |
| A reaction: This seems to be a rather desperate remark, in response to what must have been rather good hostile arguments. No one would abandon the support of reason if it was easy to acquire. You can't deny its engaging romantic defiance, though. |
| 1893 | If God foresaw evil he would presumably prevent it, and if he only foresees some things, why those things? [Sext.Empiricus] |
| Full Idea: If God had forethought for all, there would be no evil in the world, yet they say the world is full of evil. And if he forethinks some things, why those and not others? | |
| From: Sextus Empiricus (Outlines of Pyrrhonism [c.180], III.9) |