48 ideas
| 1502 | Parmenides was much more cautious about accepting ideas than his predecessors [Simplicius on Parmenides] |
| Full Idea: Parmenides would not agree with anything unless it seemed necessary, whereas his predecessors used to come up with unsubstantiated assertions. | |
| From: comment on Parmenides (fragments/reports [c.474 BCE], A28) by Simplicius - On Aristotle's 'Physics' 9.116.2- | |
| A reaction: from Eudemus |
| 10245 | One geometry cannot be more true than another [Poincaré] |
| Full Idea: One geometry cannot be more true than another; it can only be more convenient. | |
| From: Henri Poincaré (Science and Method [1908], p.65), quoted by Stewart Shapiro - Philosophy of Mathematics | |
| A reaction: This is the culminating view after new geometries were developed by tinkering with Euclid's parallels postulate. |
| 15923 | Poincaré rejected the actual infinite, claiming definitions gave apparent infinity to finite objects [Poincaré, by Lavine] |
| Full Idea: Poincaré rejected the actual infinite. He viewed mathematics that is apparently concerned with the actual infinite as actually concerning the finite linguistic definitions the putatively describe actually infinite objects. | |
| From: report of Henri Poincaré (On the Nature of Mathematical Reasoning [1894]) by Shaughan Lavine - Understanding the Infinite |
| 10180 | Mathematicians do not study objects, but relations between objects [Poincaré] |
| Full Idea: Mathematicians do not study objects, but relations between objects; it is a matter of indifference if the objects are replaced by others, provided the relations do not change. They are interested in form alone, not matter. | |
| From: Henri Poincaré (Science and Hypothesis [1902], p.20), quoted by E Reck / M Price - Structures and Structuralism in Phil of Maths §6 | |
| A reaction: This connects modern structuralism with Aritotle's interest in the 'form' of things. Contrary to the views of the likes of Frege, it is hard to see that the number '7' has any properties at all, apart from its relations. A daffodil would do just as well. |
| 9916 | Convention, yes! Arbitrary, no! [Poincaré, by Putnam] |
| Full Idea: Poincaré once exclaimed, 'Convention, yes! Arbitrary, no!'. | |
| From: report of Henri Poincaré (talk [1901]) by Hilary Putnam - Models and Reality | |
| A reaction: An interesting view. It mustn't be assumed that conventions are not rooted in something. Maybe a sort of pragmatism is implied. |
| 18203 | Avoid non-predicative classifications and definitions [Poincaré] |
| Full Idea: Never consider any objects but those capable of being defined in a finite number of word ...Avoid non-predicative classifications and definitions. | |
| From: Henri Poincaré (The Logic of Infinity [1909], p.63), quoted by Penelope Maddy - Naturalism in Mathematics II.4 |
| 448 | No necessity could produce Being either later or earlier, so it must exist absolutely or not at all [Parmenides] |
| Full Idea: What necessity impelled Being, if it did spring from nothing, to be produced later or earlier? Thus it must be absolutely, or not at all. | |
| From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1- |
| 447 | Being must be eternal and uncreated, and hence it is timeless [Parmenides] |
| Full Idea: Being has no coming-to-be and no destruction, for it is whole of limb, without motion, and without end. And it never was, nor will be, because it is now, a whole all together, one, continuous; for what creation of it will you look for? | |
| From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1- |
| 449 | Being is not divisible, since it is all alike [Parmenides] |
| Full Idea: Being is not divisible, since it is all alike. | |
| From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1- |
| 1503 | There is no such thing as nothing [Parmenides] |
| Full Idea: There is no such thing as nothing. | |
| From: Parmenides (fragments/reports [c.474 BCE], B06), quoted by Simplicius - On Aristotle's 'Physics' 9.86.27- |
| 445 | The realm of necessary non-existence cannot be explored, because it is unknowable [Parmenides] |
| Full Idea: The other way of enquiry, that IT IS NOT, and IT is bound NOT TO BE, cannot be explored, for you could neither recognise nor express that which IS NOT. | |
| From: Parmenides (fragments/reports [c.474 BCE], B02), quoted by Simplicius - On Aristotle's 'Physics' 9.116.28- |
| 21820 | Parmenides at least saw Being as the same as Nous, and separate from the sensed realm [Parmenides, by Plotinus] |
| Full Idea: Parmenides made some approach to the doctrine of Plato in identifying Being with Intellectual-Principle [Nous] while separating Real Being from the realm of sense. | |
| From: report of Parmenides (fragments/reports [c.474 BCE]) by Plotinus - The Enneads 5.1.08 | |
| A reaction: The point is that for Parmenides the One is the essence of Being, but for platonists there is something prior to and higher than Being. For Plato it is the Good; for Plotinus it is a revised (non-Being) concept of the One. |
| 452 | All our concepts of change and permanence are just names, not the truth [Parmenides] |
| Full Idea: All things that mortals have established, believing in their truth, are just a name: Becoming and Perishing, Being and Not-Being, and change of position, and alteration of bright colour. | |
| From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1- |
| 1504 | Something must be unchanging to make recognition and knowledge possible [Aristotle on Parmenides] |
| Full Idea: Parmenides and Melissus were the first to appreciate that there must be unchanging entities, if recognition and knowledge are to exist. | |
| From: comment on Parmenides (fragments/reports [c.474 BCE], A25) by Aristotle - On the Heavens 298b14 |
| 444 | The first way of enquiry involves necessary existence [Parmenides] |
| Full Idea: The first way of enquiry is the one that IT IS, and it is not possible for IT NOT TO BE, which is the way of credibility, for it follows truth. | |
| From: Parmenides (fragments/reports [c.474 BCE], B02), quoted by Simplicius - On Aristotle's 'Physics' 9.116.28- | |
| A reaction: also Proclus 'Timeus' |
| 450 | Necessity sets limits on being, in order to give it identity [Parmenides] |
| Full Idea: Powerful necessity holds Being in the bonds of a limit, which constrains it round about, because divine law decrees that Being shall not be without boundary. For it is not lacking, but if it were spatially infinite, it would lack everything. | |
| From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1- |
| 451 | Thinking implies existence, because thinking depends on it [Parmenides] |
| Full Idea: To think is the same as the thought that IT IS, for you will not find thinking without Being, on which it depends for its expression. | |
| From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1- |
| 1506 | Parmenides treats perception and intellectual activity as the same [Theophrastus on Parmenides] |
| Full Idea: Parmenides treats perception and intellectual activity as the same. | |
| From: comment on Parmenides (fragments/reports [c.474 BCE], A46) by Theophrastus - On the Senses 3.1 | |
| A reaction: cf Theaetetus pt 1 |
| 3058 | Only reason can prove the truth of facts [Parmenides] |
| Full Idea: Reason alone will prove the truth of facts. | |
| From: Parmenides (fragments/reports [c.474 BCE]), quoted by Diogenes Laertius - Lives of Eminent Philosophers 09.3.3 |
| 20014 | Actions include: the involuntary, the purposeful, the intentional, and the self-consciously autonomous [Wilson/Schpall] |
| Full Idea: There are different levels of action, including at least: unconscious and/or involuntary behaviour, purposeful or goal-directed activity, intentional action, and the autonomous acts or actions of self-consciously active human agents. | |
| From: Wilson,G/Schpall,S (Action [2012], 1) | |
| A reaction: The fourth class is obviously designed to distinguish us from the other animals. It immediately strikes me as very optimistic to distinguish four (at least) clear categories, but you have to start somewhere. |
| 20019 | Maybe bodily movements are not actions, but only part of an agent's action of moving [Wilson/Schpall] |
| Full Idea: Some say that the movement's of agent's body are never actions. It is only the agent's direct moving of, say, his leg that constitutes a physical action; the leg movement is merely caused by and/or incorporated as part of the act of moving. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.2) | |
| A reaction: [they cite Jennifer Hornsby 1980] It seems normal to deny a twitch the accolade of an 'action', so I suppose that is right. Does the continual movement of my tongue count as action? Only if I bring it under control? Does it matter? Only in forensics. |
| 20021 | Is the action the arm movement, the whole causal process, or just the trying to do it? [Wilson/Schpall] |
| Full Idea: Some philosophers have favored the overt arm movement the agent performs, some favor the extended causal process he initiates, and some prefer the relevant event of trying that precedes and 'generates' the rest. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.2) | |
| A reaction: [Davidson argues for the second, Hornsby for the third] There seems no way to settle this, and a compromise looks best. Mere movement won't do, and mere trying won't do, and whole processes get out of control. |
| 20022 | To be intentional, an action must succeed in the manner in which it was planned [Wilson/Schpall] |
| Full Idea: If someone fires a bullet to kill someone, misses, and dislodges hornets that sting him to death, this implies that an intentional action must include succeeding in a manner according to the original plan. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: [their example, compressed] This resembles Gettier's problem cases for knowledge. If the shooter deliberately and maliciously brought down the hornet's nest, that would be intentional murder. Sounds right. |
| 20023 | If someone believes they can control the lottery, and then wins, the relevant skill is missing [Wilson/Schpall] |
| Full Idea: If someone enters the lottery with the bizarre belief that they can control who wins, and then wins it, that suggest that intentional actions must not depend on sheer luck, but needs competent exercise of the relevant skill. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: A nice companion to Idea 20022, which show that a mere intention is not sufficient to motivate and explain an action. |
| 20025 | We might intend two ways to acting, knowing only one of them can succeed [Wilson/Schpall] |
| Full Idea: If an agent tries to do something by two different means, only one of which can succeed, then the behaviour is rational, even though one of them is an attempt to do an action which cannot succeed. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: [a concise account of a laborious account of an example from Bratman 1984, 1987] Bratman uses this to challenge the 'Simple View', that intention leads straightforwardly to action. |
| 20031 | On one model, an intention is belief-desire states, and intentional actions relate to beliefs and desires [Wilson/Schpall] |
| Full Idea: On the simple desire-belief model, an intention is a combination of desire-belief states, and an action is intentional in virtue of standing in the appropriate relation to these simpler terms. | |
| From: Wilson,G/Schpall,S (Action [2012], 4) | |
| A reaction: This is the traditional view found in Hume, and is probably endemic to folk psychology. They cite Bratman 1987 as the main opponent of the view. |
| 20028 | Groups may act for reasons held by none of the members, so maybe groups are agents [Wilson/Schpall] |
| Full Idea: Rational group action may involve a 'collectivising of reasons', with participants acting in ways that are not rationally recommended from the individual viewpoint. This suggests that groups can be rational, intentional agents. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: [Pettit 2003] is the source for this. Gilbert says individuals can have joint commitment; Pettit says the group can be an independent agent. The matter of shared intentions is interesting, but there is no need for the ontology to go berserk. |
| 20027 | If there are shared obligations and intentions, we may need a primitive notion of 'joint commitment' [Wilson/Schpall] |
| Full Idea: An account of mutual obligation to do something may require that we give up reductive individualist accounts of shared activity and posit a primitive notion of 'joint commitment'. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: [attributed to Margaret Gilbert 2000] If 'we' are trying to do something, that seems to give an externalist picture of intentions, rather like all the other externalisms floating around these days. I don't buy any of it, me. |
| 20016 | Strong Cognitivism identifies an intention to act with a belief [Wilson/Schpall] |
| Full Idea: A Strong Cognitivist is someone who identifies an intention with a certain pertinent belief about what she is doing or about to do. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.1) | |
| A reaction: (Sarah Paul 2009 makes this distinction) The belief, if so, seems to be as much counterfactual as factual. Hope seems to come into it, which isn't exactly a belief. |
| 20017 | Weak Cognitivism says intentions are only partly constituted by a belief [Wilson/Schpall] |
| Full Idea: A Weak Cognitivist holds that intentions are partly constituted by, but are not identical with, relevant beliefs about the action. Grice (1971) said an intention is willing an action, combined with a belief that this will lead to the action. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.1) | |
| A reaction: [compressed] I didn't find Strong Cognitivism appealing, but it seems hard to argue with some form of the weak version. |
| 20018 | Strong Cognitivism implies a mode of 'practical' knowledge, not based on observation [Wilson/Schpall] |
| Full Idea: Strong Cognitivists say intentions/beliefs are not based on observation or evidence, and are causally reliable in leading to appropriate actions, so this is a mode of 'practical' knowledge that has not been derived from observation. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.1) | |
| A reaction: [compressed - Stanford unnecessarily verbose!] I see no mention in this discussion of 'hoping' that your action will turn out OK. We are usually right to hope, but it would be foolish to say that when we reach for the salt we know we won't knock it over. |
| 20012 | Maybe the explanation of an action is in the reasons that make it intelligible to the agent [Wilson/Schpall] |
| Full Idea: Some have maintained that we explain why an agent acted as he did when we explicate how the agent's normative reasons rendered the action intelligible in his eyes. | |
| From: Wilson,G/Schpall,S (Action [2012], Intro) | |
| A reaction: Modern psychology is moving against this, by showing how hidden biases can predominate over conscious reasons (as in Kahnemann's work). I would say this mode of explanation works better for highly educated people (but you can chuckle at that). |
| 20029 | Causalists allow purposive explanations, but then reduce the purpose to the action's cause [Wilson/Schpall] |
| Full Idea: Most causalists allow that reason explanations are teleological, but say that such purposive explanations are analysable causally, where the primary reasons for the act are the guiding causes of the act. | |
| From: Wilson,G/Schpall,S (Action [2012], 3) | |
| A reaction: The authors observe that it is hard to adjudicate on this matter, and that the concept of the 'cause' of an action is unclear. |
| 20013 | It is generally assumed that reason explanations are causal [Wilson/Schpall] |
| Full Idea: The view that reason explanations are somehow causal explanations remains the dominant position. | |
| From: Wilson,G/Schpall,S (Action [2012], Intro) | |
| A reaction: I suspect that this is only because no philosopher has a better idea, and the whole issue is being slowly outflanked by psychology. |
| 5081 | There could be movement within one thing, as there is within water [Aristotle on Parmenides] |
| Full Idea: Why does it follow from there being only one thing that it is unmoving, since, for example, water moves internally while remaining one? | |
| From: comment on Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Physics 186a16 | |
| A reaction: One suspects that Parmenides wasn't used to critical questions like this, and would have sharpened up his theory if it had been subjected to criticism. How big was the One? Maybe Aristotle is the real father of philosophy. |
| 1509 | The one can't be divisible, because if it was it could be infinitely divided down to nothing [Parmenides, by Simplicius] |
| Full Idea: Since the one is everywhere alike, then if it is divisible, it will be equally divisible everywhere….so let it be divided everywhere. It is obvious that nothing will remain and the whole will vanish, and so (if it is compound) it is composed of nothing. | |
| From: report of Parmenides (fragments/reports [c.474 BCE]) by Simplicius - On Aristotle's 'Physics' 9.139.5- | |
| A reaction: he is quoting Porphyry |
| 20900 | Defenders of the One say motion needs the void - but that is not part of Being [Parmenides, by Aristotle] |
| Full Idea: Defenders of the One say that there could not be motion without a void, and that void is what does not exist, and that nothing that is not belongs to being. | |
| From: report of Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 325a26 | |
| A reaction: This is why motion is an illusion, a view also supported by the paradoxes of Zeno of Elea. Aristotle goes on to give Democritus's response to this idea. Parmenides was contemplating 'void', before Democritus got to it. |
| 226 | The one is without any kind of motion [Parmenides] |
| Full Idea: The one is without any kind of motion. | |
| From: Parmenides (fragments/reports [c.474 BCE]), quoted by Plato - Parmenides 139a |
| 1505 | Reason sees reality as one, the senses see it as many [Aristotle on Parmenides] |
| Full Idea: Since he is forced to be guided by appearances, he assumes that the one exists from the viewpoint of reason, but that a plurality exists from the viewpoint of the sense, and so he posits two principles and causes - hot and cold. | |
| From: comment on Parmenides (fragments/reports [c.474 BCE], A24) by Aristotle - Metaphysics 986b27- | |
| A reaction: A profound thought. Empiricists emphasies experience, and end up with fragmented reality. Reason explains experience, and in the process sees the world as unities (like objects), though a single unity is going too far. |
| 453 | Reality is symmetrical and balanced, like a sphere, with no reason to be greater one way rather than another [Parmenides] |
| Full Idea: Since there is a spatial limit, it is complete on every side, like the mass of a well-rounded sphere, equally balanced from its centre in every direction; for it is not bound to be at all either greater or less in this direction or that. | |
| From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1- |
| 555 | People who say that the cosmos is one forget that they must explain movement [Aristotle on Parmenides] |
| Full Idea: Those who assert that the universe is one and a single nature, when they try to give the causes of generation and destruction, miss out the cause of movement. | |
| From: comment on Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Metaphysics 988b |
| 1792 | He taught that there are two elements, fire the maker, and earth the matter [Parmenides, by Diog. Laertius] |
| Full Idea: He taught that there were two elements, fire and earth; and that one of them occupies the place of the maker, the other that of the matter. | |
| From: report of Parmenides (fragments/reports [c.474 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Pa.2 |
| 15877 | The aim of science is just to create a comprehensive, elegant language to describe brute facts [Poincaré, by Harré] |
| Full Idea: In Poincaré's view, we try to construct a language within which the brute facts of experience are expressed as comprehensively and as elegantly as possible. The job of science is the forging of a language precisely suited to that purpose. | |
| From: report of Henri Poincaré (The Value of Science [1906], Pt III) by Rom Harré - Laws of Nature 2 | |
| A reaction: I'm often struck by how obscure and difficult our accounts of self-evident facts can be. Chairs are easy, and the metaphysics of chairs is hideous. Why is that? I'm a robust realist, but I like Poincaré's idea. He permits facts. |
| 5115 | It is feeble-minded to look for explanations of everything being at rest [Aristotle on Parmenides] |
| Full Idea: For people to ignore the evidence of their senses and look for an explanation for everything being at rest is feeble-minded. | |
| From: comment on Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Physics 253a32 | |
| A reaction: Not exactly an argument, but an interestingly robust assertion of commonsense against dodgy arguments. Aristotle is not exactly an empiricist, but he is on that side of the fence. |
| 13217 | The void can't exist, and without the void there can't be movement or separation [Parmenides, by Aristotle] |
| Full Idea: Some philosophers thought what is must be one and immovable. The void, they say, is not: but unless there is a void what is cannot be moved, nor can it be many, since there is nothing to keep things apart. | |
| From: report of Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 325a06 | |
| A reaction: Somehow this doesn't seem very persuasive any more! I suppose we would distinguish various degrees of void, and assert the existence of sufficient void to allow movement and separation. We must surely agree that total nothingness doesn't exist. |
| 22918 | What could have triggered the beginning [of time and being]? [Parmenides] |
| Full Idea: What need would have aroused it later or sooner, starting from nothing to come into being? | |
| From: Parmenides (fragments/reports [c.474 BCE]), quoted by Robin Le Poidevin - Travels in Four Dimensions 02 'Everything' | |
| A reaction: [Barnes 1982:178] This remains an excellent question. The last I heard was a 'quantum fluctuation', but that seems to be an event, which therefore needs time. |
| 1791 | He was the first person to say the earth is spherical [Parmenides, by Diog. Laertius] |
| Full Idea: He was the first person who asserted that the earth was of a spherical form. | |
| From: report of Parmenides (fragments/reports [c.474 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Pa.2 |
| 1794 | He was the first to discover the identity of the Morning and Evening Stars [Parmenides, by Diog. Laertius] |
| Full Idea: He appears to have been the first to discover that Hesperus and Lucifer were the same star. | |
| From: report of Parmenides (fragments/reports [c.474 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Pa.3 | |
| A reaction: This is the famous example used by Frege to discuss reference and meaning. |