50 ideas
| 4456 | Epistemological Ockham's Razor demands good reasons, but the ontological version says reality is simple [Moreland] |
| Full Idea: Ockham's Razor has an epistemological version, which says we should not multiply existences or explanations without adequate reason, and an ontological version, which says reality is simple, and so a simpler ontology represents it more accurately. | |
| From: J.P. Moreland (Universals [2001], Ch.2) | |
| A reaction: A nice distinction. Is it reality which is simple, or us? One shouldn't write off the ontological version. If one explanation is simpler than the others, there may be a reason in nature for that. |
| 12452 | Our dislike of contradiction in logic is a matter of psychology, not mathematics [Brouwer] |
| Full Idea: Not to the mathematician, but to the psychologist, belongs the task of explaining why ...we are averse to so-called contradictory systems in which the negative as well as the positive of certain propositions are valid. | |
| From: Luitzen E.J. Brouwer (Intuitionism and Formalism [1912], p.79) | |
| A reaction: Was the turning point of Graham Priest's life the day he read this sentence? I don't agree. I take the principle of non-contradiction to be a highly generalised observation of how the world works (and Russell agrees with me). |
| 15941 | For intuitionists excluded middle is an outdated historical convention [Brouwer] |
| Full Idea: From the intuitionist standpoint the dogma of the universal validity of the principle of excluded third in mathematics can only be considered as a phenomenon of history of civilization, like the rationality of pi or rotation of the sky about the earth. | |
| From: Luitzen E.J. Brouwer (works [1930]), quoted by Shaughan Lavine - Understanding the Infinite VI.2 | |
| A reaction: [Brouwer 1952:510-11] |
| 18119 | Mathematics is a mental activity which does not use language [Brouwer, by Bostock] |
| Full Idea: Brouwer made the rather extraordinary claim that mathematics is a mental activity which uses no language. | |
| From: report of Luitzen E.J. Brouwer (Mathematics, Science and Language [1928]) by David Bostock - Philosophy of Mathematics 7.1 | |
| A reaction: Since I take language to have far less of a role in thought than is commonly believed, I don't think this idea is absurd. I would say that we don't use language much when we are talking! |
| 18247 | Brouwer saw reals as potential, not actual, and produced by a rule, or a choice [Brouwer, by Shapiro] |
| Full Idea: In his early writing, Brouwer took a real number to be a Cauchy sequence determined by a rule. Later he augmented rule-governed sequences with free-choice sequences, but even then the attitude is that Cauchy sequences are potential, not actual infinities. | |
| From: report of Luitzen E.J. Brouwer (works [1930]) by Stewart Shapiro - Philosophy of Mathematics 6.6 | |
| A reaction: This is the 'constructivist' view of numbers, as espoused by intuitionists like Brouwer. |
| 12451 | Scientific laws largely rest on the results of counting and measuring [Brouwer] |
| Full Idea: A large part of the natural laws introduced by science treat only of the mutual relations between the results of counting and measuring. | |
| From: Luitzen E.J. Brouwer (Intuitionism and Formalism [1912], p.77) | |
| A reaction: His point, I take it, is that the higher reaches of numbers have lost touch with the original point of the system. I now see the whole issue as just depending on conventions about the agreed extension of the word 'number'. |
| 18118 | Brouwer regards the application of mathematics to the world as somehow 'wicked' [Brouwer, by Bostock] |
| Full Idea: Brouwer regards as somehow 'wicked' the idea that mathematics can be applied to a non-mental subject matter, the physical world, and that it might develop in response to the needs which that application reveals. | |
| From: report of Luitzen E.J. Brouwer (Mathematics, Science and Language [1928]) by David Bostock - Philosophy of Mathematics 7.1 | |
| A reaction: The idea is that mathematics only concerns creations of the human mind. It presumably has no more application than, say, noughts-and-crosses. |
| 12454 | Intuitionists only accept denumerable sets [Brouwer] |
| Full Idea: The intuitionist recognises only the existence of denumerable sets. | |
| From: Luitzen E.J. Brouwer (Intuitionism and Formalism [1912], p.80) | |
| A reaction: That takes you up to omega, but not beyond, presumably because it then loses sight of the original intuition of 'bare two-oneness' (Idea 12453). I sympathise, but the word 'number' has shifted its meaning a lot these days. |
| 12453 | Neo-intuitionism abstracts from the reuniting of moments, to intuit bare two-oneness [Brouwer] |
| Full Idea: Neo-intuitionism sees the falling apart of moments, reunited while remaining separated in time, as the fundamental phenomenon of human intellect, passing by abstracting to mathematical thinking, the intuition of bare two-oneness. | |
| From: Luitzen E.J. Brouwer (Intuitionism and Formalism [1912], p.80) | |
| A reaction: [compressed] A famous and somewhat obscure idea. He goes on to say that this creates one and two, and all the finite ordinals. |
| 8728 | Intuitionist mathematics deduces by introspective construction, and rejects unknown truths [Brouwer] |
| Full Idea: Mathematics rigorously treated from the point of view of deducing theorems exclusively by means of introspective construction, is called intuitionistic mathematics. It deviates from classical mathematics, which believes in unknown truths. | |
| From: Luitzen E.J. Brouwer (Consciousness, Philosophy and Mathematics [1948]), quoted by Stewart Shapiro - Thinking About Mathematics 1.2 | |
| A reaction: Clearly intuitionist mathematics is a close cousin of logical positivism and the verification principle. This view would be anathema to Frege, because it is psychological. Personally I believe in the existence of unknown truths, big time! |
| 4474 | Existence theories must match experience, possibility, logic and knowledge, and not be self-defeating [Moreland] |
| Full Idea: A theory of existence should 1) be consistent with what actually exists, 2) be consistent with what could exist, 3) not make existence impossible (e.g. in space-time), 4) not violate logic, 5) make knowing the theory possible. | |
| From: J.P. Moreland (Universals [2001], Ch.6) | |
| A reaction: A nice bit of metaphilosophical analysis. I still doubt whether a theory of existence is possible (something has to be 'given' a priori), but this is a good place to start the attempt. |
| 4461 | Tropes are like Hume's 'impressions', conceived as real rather than as ideal [Moreland] |
| Full Idea: Tropes are (says Campbell) substances (in Hume's sense), and indeed resemble his impressions conceived realistically rather than idealistically. | |
| From: J.P. Moreland (Universals [2001], Ch.3) | |
| A reaction: An interesting link. It doesn't get rid of the problem Hume has, of saying when two impressions are the same. Are they types or tokens? Trope-theory claims they are tokens. Hume's ontology includes 'resemblance'. |
| 4462 | A colour-trope cannot be simple (as required), because it is spread in space, and so it is complex [Moreland] |
| Full Idea: A property-instance must be spread out in space, or it is not clear how a colour nature can be present, but then it has to be a complex entity, and tropes are supposed to be simple entities. | |
| From: J.P. Moreland (Universals [2001], Ch.3) | |
| A reaction: Seems a fair point. Nothing else in reality can be sharply distinguished, so why should 'simple' and 'complex'? |
| 4463 | In 'four colours were used in the decoration', colours appear to be universals, not tropes [Moreland] |
| Full Idea: If a decorator says that they used four colours to decorate a house, four tropes is not what was meant, and the statement seems to view colours as universals. | |
| From: J.P. Moreland (Universals [2001], Ch.3) | |
| A reaction: Although I am suspicious of using language to deduce ontology, you have to explain why certain statements (like this) are even possible to make. |
| 4451 | If properties are universals, what distinguishes two things which have identical properties? [Moreland] |
| Full Idea: If properties are universals, what account can be given of the individuation of two entities that have all their pure properties in common? | |
| From: J.P. Moreland (Universals [2001], Ch.1) | |
| A reaction: Is this a big problem? Maybe only a space-time location can do it. Or, in the nice case where the universe is just two identical spheres, it may be impossible. |
| 4453 | One realism is one-over-many, which may be the model/copy view, which has the Third Man problem [Moreland] |
| Full Idea: One version of realism says that the universal does not enter into the being of its instances, and thus is a One-Over-Many. One version of this is the model/copy view, but this is not widely held, because of difficulties such as the Third Man Argument. | |
| From: J.P. Moreland (Universals [2001], Ch.1) | |
| A reaction: This presumably arises if the model is held to have the properties of the copy (self-predication), and looks like a bad theory |
| 4464 | Realists see properties as universals, which are single abstract entities which are multiply exemplifiable [Moreland] |
| Full Idea: Traditional realism is the view that a property is a universal construed as a multiply exemplifiable abstract entity that is a numerically identical constituent in each of its instances. | |
| From: J.P. Moreland (Universals [2001], Ch.4) | |
| A reaction: Put like that, it seems hard to commit oneself fully to realism. How can two red buses contain one abstract object spread out between them. Common sense says there are two 'rednesses' which resemble one another, which is a version of nominalism. |
| 4450 | The traditional problem of universals centres on the "One over Many", which is the unity of natural classes [Moreland] |
| Full Idea: Historically the problem of universals has mainly been about the "One over Many", which involves giving an account of the unity of natural classes. | |
| From: J.P. Moreland (Universals [2001], Ch.1) | |
| A reaction: This still strikes me as the main problem (rather than issues of language). If universals are not natural, they must be analysed as properties, which break down into causation, which is seen as a human convention. |
| 4449 | Evidence for universals can be found in language, communication, natural laws, classification and ideals [Moreland] |
| Full Idea: Those who believe in universals appeal to the meaningfulness of language, the lawlike nature of causation, the inter-subjectivity of thinking, our ability to classify new entities, gradation, and the need for perfect standards or paradigms. | |
| From: J.P. Moreland (Universals [2001], Ch.1) | |
| A reaction: Of these, language and communication ought to be explicable by convention, but classification and natural laws look to me like the best evidence. |
| 4454 | The One-In-Many view says universals have abstract existence, but exist in particulars [Moreland] |
| Full Idea: Another version of realism says is One-In-Many, where the universal is not another particular, but is literally in the instances. The universal is an abstract entity, in the instances by means of a primitive non-spatiotemporal tie of predication. | |
| From: J.P. Moreland (Universals [2001], Ch.1) | |
| A reaction: This sounds like Aristotle (and is Loux's view of properties and relations). If they are abstract, why must they be confined to particulars? |
| 4452 | Maybe universals are real, if properties themselves have properties, and relate to other properties [Moreland] |
| Full Idea: Realism about universals is supported by the phenomenon of abstract reference - that is the fact that properties themselves have properties ('red is a colour'), and stand in relation to other properties ('red is more like orange than like blue'). | |
| From: J.P. Moreland (Universals [2001], Ch.1) | |
| A reaction: While a property may be an obviously natural feature, properties of properties seem more likely to be the produce of human perception and convention. It is a good argument, though. |
| 4467 | A naturalist and realist about universals is forced to say redness can be both moving and stationary [Moreland] |
| Full Idea: If a property is held to be at the location of the particular, then if there are two objects having the same property, and one object is stationary and the other is moving, the realist is forced to say that the universal is both moving and at rest. | |
| From: J.P. Moreland (Universals [2001], Ch.4) | |
| A reaction: The target of this comment is D.M.Armstrong. The example nicely illustrates the problem of trying to combine science and metaphysics. It pushes you back to Platonism, but that seems wrong too… |
| 4469 | There are spatial facts about red particulars, but not about redness itself [Moreland] |
| Full Idea: When one attends to something existing in space, one attends to an instance of redness, not to redness itself (which is a colour, which resembles orange). The facts about red itself are not spatial facts, but are traditionally seen as a priori synthetic. | |
| From: J.P. Moreland (Universals [2001], Ch.4) | |
| A reaction: This is the fact that properties can themselves have properties (and so on?), which seems to take us further and further from the natural world. |
| 4468 | How could 'being even', or 'being a father', or a musical interval, exist naturally in space? [Moreland] |
| Full Idea: Many properties (being even) and relations (musical intervals, being a father) are such that it is not clear what it would mean to take them as natural things existing in space. | |
| From: J.P. Moreland (Universals [2001], Ch.4) | |
| A reaction: 'Being even' certainly seems to be a property, and it is a struggle to see how it could exist in space, unless it is a set of actual or potential brain states. |
| 4472 | Redness is independent of red things, can do without them, has its own properties, and has identity [Moreland] |
| Full Idea: Four arguments for Platonism: 1) there are truths about redness (it's a colour) even if nothing red exists, 2) redness does not depend on particulars, 3) most universals are at some time not exemplified, 4) universals satisfy the criteria of existence. | |
| From: J.P. Moreland (Universals [2001], Ch.6) | |
| A reaction: This adds up to quite a good case, particularly the point that things can be said about redness which are independent of any particular, but the relationships between concepts and the brain seems at the heart of the problem. |
| 4459 | Moderate nominalism attempts to embrace the existence of properties while avoiding universals [Moreland] |
| Full Idea: Moderate nominalism attempts to embrace the existence of properties while avoiding universals. | |
| From: J.P. Moreland (Universals [2001], Ch.2) | |
| A reaction: Clearly there is going to be quite a struggle to make sense of 'exists' here (Russell tries 'subsists). Presumably each property must be a particular? |
| 4458 | Unlike Class Nominalism, Resemblance Nominalism can distinguish natural from unnatural classes [Moreland] |
| Full Idea: Resemblance Nominalism is clearly superior to Class Nominalism, since the former offers a clear ground for distinguishing between natural and unnatural classes. | |
| From: J.P. Moreland (Universals [2001], Ch.2) | |
| A reaction: Important. It seems evident to me that there are natural classes, and the only ground for this claim would be either the resemblance or the identity of properties. |
| 4457 | There can be predicates with no property, and there are properties with no predicate [Moreland] |
| Full Idea: Linguistic predicates are neither sufficient nor necessary for specifying a property. Predicates can be contrived which express no property, properties are far more numerous than linguistic predicates, and properties are what make predicates apply. | |
| From: J.P. Moreland (Universals [2001], Ch.2) | |
| A reaction: This seems to me conclusive, and is a crucial argument against anyone who thinks that our metaphysics can simply be inferred from our language. |
| 4471 | We should abandon the concept of a property since (unlike sets) their identity conditions are unclear [Moreland] |
| Full Idea: Some argue that compared to sets, the identity conditions for properties are obscure, and so properties, including realist depictions of them, should be rejected. | |
| From: J.P. Moreland (Universals [2001], Ch.6) | |
| A reaction: I have never thought that difficulty in precisely identifying something was a good reason for denying its existence. Consider low morale in a work force. 2nd thoughts: I like this! |
| 1212 | Replacing timbers on Theseus' ship was the classic illustration of the problem of growth and change [Plutarch] |
| Full Idea: At intervals they removed old timbers from the preserved ship and replaced them with sound ones, so the ship became a classic illustration for the philosophers of the disputed question of growth and change, some saying it was the same, others different. | |
| From: Plutarch (Life of Theseus [c.85], 23) |
| 4476 | Most philosophers think that the identity of indiscernibles is false [Moreland] |
| Full Idea: Most philosophers think that the identity of indiscernibles is false. | |
| From: J.P. Moreland (Universals [2001], Ch.7) | |
| A reaction: This is as opposed to the generally accepted 'indiscernibility of identicals'. 'Discernment' is an epistemological concept, and 'identity' is an ontological concept. |
| 5958 | The sun is always bright; it doesn't become bright when it emerges [Plutarch] |
| Full Idea: The sun doesn't become bright when it emerges from the clouds; it always is bright. | |
| From: Plutarch (26: Oracles in Decline [c.85], §39) | |
| A reaction: Not an argument, but a nice appeal to common sense, like Russell's example of the cat that disappears behind the furniture and then reappears. To disagree with Plutarch here strikes me as the road to philosophical absurdity. |
| 5959 | Some philosophers say the soul is light [Plutarch] |
| Full Idea: Some philosophers hold that the soul is in its essence light. | |
| From: Plutarch (75: Is 'Live Unknown' a Wise Precept? [c.85], §6) | |
| A reaction: A nice idea, to rival the stoic view that the soul is fire. It is understandable to propose that the soul is some sort of lightweight and fast moving matter. How else could thought be achieved physically? Nowadays, parallel processing is our only model. |
| 5960 | When the soul is intelligent and harmonious, it is part of god and derives from god [Plutarch] |
| Full Idea: The soul, when it has partaken of intelligence and reason and concord, is not merely a work but also a part of god and has come to be not by his agency but both from him as source and out of his substance. | |
| From: Plutarch (67: Platonic Questions [c.85], II.1001) | |
| A reaction: A most intriguing shift of view from earlier concepts of the psuché. How did this come about? This man is a pagan. The history is in the evolution of Platonism. See 'The Middle Platonists' by John Dillon. Davidson is also very impressed by reason. |
| 4460 | Abstractions are formed by the mind when it concentrates on some, but not all, the features of a thing [Moreland] |
| Full Idea: If something is 'abstract' it is got before the mind by an act of abstraction, that is, by concentrating attention on some (but not all) of what is presented. | |
| From: J.P. Moreland (Universals [2001], Ch.3) | |
| A reaction: Presumably it usually involves picking out the behavioural or causal features, and leaving out the physical features - though I suppose it works for physical properties too… |
| 5952 | Rather than being the whole soul, maybe I am its chief part? [Plutarch] |
| Full Idea: Is each of us not the soul, but the chief part of the soul, by which we think and reason and act, all the other parts of soul as well as of body being mere instruments of its power? | |
| From: Plutarch (74: Reply to Colotes [c.85], §1119) | |
| A reaction: Socrates is associated with the idea that I am my whole soul (Idea 1650). Plutarch represents an interesting development, which may lead both to the Christian 'soul' and to the Cartesian 'ego'. I think Plutarch is right, but what is the 'soul'? |
| 5951 | If atoms have no qualities, they cannot possibly produce a mind [Plutarch] |
| Full Idea: Perception, mind, intelligence and thought cannot so much as be conceived, even with the best will, as arising among void and atoms, things which taken separately have no quality. | |
| From: Plutarch (74: Reply to Colotes [c.85], §1112) | |
| A reaction: A nice articulation of the intuition of all anti-physicalists. Plutarch would have to rethink his position carefully if he learned of the sheer number of connections in the brain, and of the theory of natural selection. His challenge remains, though. |
| 5963 | Some say emotion is a sort of reason, and others say virtue concerns emotion [Plutarch] |
| Full Idea: Some philosophers make the emotions varieties of reason, on the ground that all desire and grief and anger are judgments, while others declare that the virtues have to do with emotions, as when fear is the province of courage. | |
| From: Plutarch (68: Generation of the soul in 'Timaeus' [c.85], 1025d) | |
| A reaction: The second idea comes from Aristotle, but the second is interesting, and corresponds to the views coming from modern neuroscience, where even the most basic thought seems to involve emotion. What could be the motivation for 'pure' reason? |
| 4455 | It is always open to a philosopher to claim that some entity or other is unanalysable [Moreland] |
| Full Idea: It is always open to a philosopher to claim that some entity or other is unanalysable. | |
| From: J.P. Moreland (Universals [2001], Ch.2) | |
| A reaction: For example, Davidson on truth. There is an onus to demonstrate why all attempted analyses fail. |
| 10117 | Intuitonists in mathematics worried about unjustified assertion, as well as contradiction [Brouwer, by George/Velleman] |
| Full Idea: The concern of mathematical intuitionists was that the use of certain forms of inference generates, not contradiction, but unjustified assertions. | |
| From: report of Luitzen E.J. Brouwer (Intuitionism and Formalism [1912]) by A.George / D.J.Velleman - Philosophies of Mathematics Ch.6 | |
| A reaction: This seems to be the real origin of the verificationist idea in the theory of meaning. It is a hugely revolutionary idea - that ideas are not only ruled out of court by contradiction, but that there are other criteria which should also be met. |
| 20796 | Action needs an affinity for a presentation, and an impulse toward the affinity [Plutarch] |
| Full Idea: The sceptics say there are three movements of the soul: presentation, impulse and assent. …And action requires two things: a presentation of something to which one has an affinity, and an impulse toward what is presented as an object of affinity. | |
| From: Plutarch (74: Reply to Colotes [c.85], 1122c) | |
| A reaction: Not much reasoning involved in this account, which the sceptics say is compatible with suspension of judgement. |
| 1477 | Being manly and brave is the result of convention, not of human nature [Plutarch] |
| Full Idea: Manliness is not a natural human attribute, otherwise women would be just as brave. It is due to pressure from laws, and this pressure has no free will, but is a slave of convention and criticism. | |
| From: Plutarch (64: Gryllus - on Rationality in Animals [c.85], 988c) | |
| A reaction: This is the first glimmerings of seeing gender as a cultural creation, rather than as a fact. Presumably he takes the same view of some of the supposed feminine virtues. |
| 1478 | Animals don't value pleasure, as they cease sexual intercourse after impregnation [Plutarch] |
| Full Idea: Animals of both sexes cease to have intercourse after impregnation; that shows how little animals value pleasure, and that nature is all that counts. | |
| From: Plutarch (64: Gryllus - on Rationality in Animals [c.85], 990d) | |
| A reaction: A famous monkey had an implant to stimulate pleasure, and a button to trigger it. It apparently would have starved to death rather than release the button. Animal sex is dull? |
| 5948 | The good life involves social participation, loyalty, temperance and honesty [Plutarch] |
| Full Idea: To live the good life is to live a life of participation in society, of loyalty to friends, of temperance and honest dealing. | |
| From: Plutarch (74: Reply to Colotes [c.85], §1108) | |
| A reaction: 'Participation in society' is the interesting one. This might translate as 'doing your duty', or as 'leading a well-rounded life'. Solitude is wrong if you are indebted to others, and it is unhealthy if you are not. Is solitude really immoral, though? |
| 1479 | Animals have not been led into homosexuality, because they value pleasure very little [Plutarch] |
| Full Idea: Because animals value pleasure very little, they have not been led into sex between males or between females. | |
| From: Plutarch (64: Gryllus - on Rationality in Animals [c.85], 990d) |
| 5950 | If only atoms exist, how do qualities arise when the atoms come together? [Plutarch] |
| Full Idea: If you accept atomism, you must show how bodies without quality have given rise to qualities of every kind by the mere fact of coming together. For example, how has the quality called 'hot' been imposed on the atoms? | |
| From: Plutarch (74: Reply to Colotes [c.85], §1111) | |
| A reaction: This argument is still significant in current philosophy of mind. If temperature is 'mean kinetic energy', you are left wondering where the energy came from, and why minds experience the heat. This is the 'Hard Question'. |
| 4473 | 'Presentism' is the view that only the present moment exists [Moreland] |
| Full Idea: 'Presentism' is the view that only the present moment exists. | |
| From: J.P. Moreland (Universals [2001], Ch.6) | |
| A reaction: And Greek scepticism doubted even the present, since there is no space between past and future. It is a delightfully vertigo-inducing idea. |
| 5974 | People report seeing through rocks, or over the horizon, or impossibly small works [Plutarch] |
| Full Idea: It is said that Lynceus could see through rock and tree, and a lookout in Sicily saw Carthaginian ships a day and a half away, and Callicrates and Myrmecides are said to fashion carriages canopied with the wings of fly, and write on sesame seeds. | |
| From: Plutarch (72: Against Stoics on common Conceptions [c.85], 1083e) | |
| A reaction: A warning from Plutarch against believing everything you hear! |
| 5957 | Absurd superstitions make people atheist, not disharmony in nature [Plutarch] |
| Full Idea: Men have never thought the universe godless on the ground of detecting some fault in stars or seasons; ..it is the ridiculous things that superstition does that makes people say it would be better if there were no gods at all. | |
| From: Plutarch (14: Superstition [c.85], §12) | |
| A reaction: Not true, I would say. Absurd superstitions do discredit belief in the supernatural, but earthquakes are a disharmony in nature, and a nasty one at that. Nowadays we have other explanations to rival those of religion. |
| 5955 | No one will ever find a city that lacks religious practices [Plutarch] |
| Full Idea: A city without holy places and gods, without any observance of prayers, oaths, oracles, sacrifices for blessings received or rites to avert evils, no traveller has ever seen or will ever see. | |
| From: Plutarch (74: Reply to Colotes [c.85], §1125) | |
| A reaction: The nearest you might get would be Soviet Moscow, but in 1973 I saw a man there jeering at a woman who was kneeling in the street outside a closed church. Plutarch would be stunned at the decline in religious practices in modern Europe. |