15 ideas
1507 | We don't have time for infinite quantity, but we do for infinite divisibility, because time is also divisible [Aristotle on Zeno of Elea] |
Full Idea: Although it is impossible to make contact in a finite time with things that are infinite in quantity, it is possible to do so with things that are infinitely divisible, since the time itself is also infinite in this way. | |
From: comment on Zeno (Elea) (fragments/reports [c.450 BCE], A25) by Aristotle - Physics 233a21 |
5109 | The fast runner must always reach the point from which the slower runner started [Zeno of Elea, by Aristotle] |
Full Idea: Zeno's so-called 'Achilles' claims that the slowest runner will never be caught by the fastest runner, because the one behind has first to reach the point from which the one in front started, and so the slower one is bound always to be in front. | |
From: report of Zeno (Elea) (fragments/reports [c.450 BCE]) by Aristotle - Physics 239b14 | |
A reaction: The point is that the slower runner will always have moved on when the faster runner catches up with the starting point. We must understand how humble the early Greeks felt when they confronted arguments like this. It was like a divine revelation. |
1512 | Zeno is wrong that one grain of millet makes a sound; why should one grain achieve what the whole bushel does? [Aristotle on Zeno of Elea] |
Full Idea: Zeno is wrong in arguing that the tiniest fragment of millet makes a sound; there is no reason why the fragment should be able to move in any amount of time the air which the whole bushel moved as it fell. | |
From: comment on Zeno (Elea) (fragments/reports [c.450 BCE], A29) by Aristotle - Physics 250a16 |
1508 | Zeno's arrow paradox depends on the assumption that time is composed of nows [Aristotle on Zeno of Elea] |
Full Idea: Zeno's third argument claims that a moving arrow is still. Here the conclusion depends on assuming that time is composed of nows; if this assumption is not granted, the argument fails. | |
From: comment on Zeno (Elea) (fragments/reports [c.450 BCE], A27?) by Aristotle - Physics 239b5 |
7720 | Two things can only resemble one another in some respect, and that may reintroduce a universal [Lowe] |
Full Idea: A problem for resemblance nominalism is that in saying that two particulars 'resemble' one another, it is necessary to specify in what respect they do so (e.g. colour, shape, size), and this threatens to reintroduce what appears to be talk of universals. | |
From: E.J. Lowe (Locke on Human Understanding [1995], Ch.7) | |
A reaction: We see resemblance between faces instantly, long before we can specify the 'respects' of the resemblance. This supports the Humean hard-wired view of resemblance, rather than some appeal to Platonic universals. |
7712 | On substances, Leibniz emphasises unity, Spinoza independence, Locke relations to qualities [Lowe] |
Full Idea: Later philosophers emphasised different strands of Aristotle's concept of substances: Leibniz (in his theory of monads) emphasised their unity; Spinoza emphasised their ontological independence; Locke emphasised their role in relation to qualities. | |
From: E.J. Lowe (Locke on Human Understanding [1995], Ch.4) | |
A reaction: Note that this Aristotelian idea had not been jettisoned in the late seventeenth century, unlike other Aristotelianisms. I think it is only with the success of atomism in chemistry that the idea of substance is forced to recede. |
12185 | Logical necessity is epistemic necessity, which is the old notion of a priori [Edgington, by McFetridge] |
Full Idea: Edgington's position is that logical necessity is an epistemic notion: epistemic necessity which, she claims, is the old notion of the a priori. Like Kripke, she thinks this is two-way independent of metaphysical necessity. | |
From: report of Dorothy Edgington (Epistemic and Metaphysical Possibility [1985]) by Ian McFetridge - Logical Necessity: Some Issues §1 | |
A reaction: [her paper was unpublished] She hence thinks an argument can be logically valid, while metaphysically its conclusion may not follow. Dubious, though I think I favour the view that logical necessity is underwritten by metaphysical necessity. |
7710 | Perception is a mode of belief-acquisition, and does not involve sensation [Lowe] |
Full Idea: According to one school of thought, perception is simply a mode of belief-acquisition,and there is no reason to suppose that any element of sensation is literally involved in perception. | |
From: E.J. Lowe (Locke on Human Understanding [1995], Ch.3) | |
A reaction: Blindsight would be an obvious supporting case for this view. I think this point is crucial in understanding what is wrong with Jackson's 'knowledge argument' (involving Mary, see Idea 7377). Sensation gives knowledge, so it can't be knowledge. |
7711 | Science requires a causal theory - perception of an object must be an experience caused by the object [Lowe] |
Full Idea: Only a causal theory of perception will respect the facts of physiology and physics ...meaning a theory which maintains that for a subject to perceive a physical object the subject should enjoy some appropriate perceptual experience caused by the object. | |
From: E.J. Lowe (Locke on Human Understanding [1995], Ch.3) | |
A reaction: If I hallucinate an object, then presumably I am not allowed to say that I 'perceive' it, but that seems to make the causal theory an idle tautology. If we are in virtual reality then there aren't any objects. |
7714 | Personal identity is a problem across time (diachronic) and at an instant (synchronic) [Lowe] |
Full Idea: There is the question of the identity of a person over or across time ('diachronic' personal identity), and there is also the question of what makes for personal identity at a time ('synchronic' personal identity). | |
From: E.J. Lowe (Locke on Human Understanding [1995], Ch.5) | |
A reaction: This seems to me to be the first and most important distinction in the philosophy of personal identity, and they regularly get run together. Locke, for example, has an account of synchronic identity, which is often ignored. It applies to objects too. |
7715 | Mentalese isn't a language, because it isn't conventional, or a means of public communication [Lowe] |
Full Idea: 'Mentalese' would be neither conventional nor a means of public communication so that even to call it a language is seriously misleading. | |
From: E.J. Lowe (Locke on Human Understanding [1995], Ch.7) | |
A reaction: It is, however, supposed to contain symbolic representations which are then used as tokens for computation, so it seems close to a language, if (for example) symbolic logic or mathematics were accepted as languages. But who understands it? |
7722 | If meaning is mental pictures, explain "the cat (or dog!) is NOT on the mat" [Lowe] |
Full Idea: If meaning is a private mental picture, what does 'the cat is NOT on the mat' mean, and how does it differ from 'the dog is not on the mat?'. | |
From: E.J. Lowe (Locke on Human Understanding [1995], Ch.7) | |
A reaction: Not insurmountable. We picture an empty mat, combined with a cat (or whatever) located somewhere else. A mental 'picture' of something shouldn't be contrued as a single image in a neat black frame. |
454 | If there are many things they must have a finite number, but there must be endless things between them [Zeno of Elea] |
Full Idea: It things are many, they can't be more or less than they are, so they must be finite, but also there must be endless things between each thing, so they must be infinite. | |
From: Zeno (Elea) (fragments/reports [c.450 BCE], B3), quoted by Simplicius - On Aristotle's 'Physics' 140.29 |
455 | That which moves, moves neither in the place in which it is, nor in that in which it is not [Zeno of Elea] |
Full Idea: That which moves, moves neither in the place in which it is, nor in that in which it is not. | |
From: Zeno (Elea) (fragments/reports [c.450 BCE], B4), quoted by (who?) - where? |
1511 | If everything is in a place, what is the place in? Place doesn't exist [Zeno of Elea, by Simplicius] |
Full Idea: If there is a place it will be in something, because everything that exists is in something. But what is in something is in a place. Therefore the place will be in a place, and so on ad infinitum. Therefore, there is no such thing as place. | |
From: report of Zeno (Elea) (fragments/reports [c.450 BCE], B3) by Simplicius - On Aristotle's 'Physics' 9.562.3 |