69 ideas
3879 | Philosophy aims to provide a theory of everything [Scruton] |
Full Idea: Philosophy studies everything: it tries to provide a theory of the whole of things. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 1.2) | |
A reaction: Good, but you can't avoid value-judgements about which things are important; philosophers place more value on moral theories than on theories about glacier movement. There is a tension in philosophy between human and eternal concerns. |
3891 | If p entails q, then p is sufficient for q, and q is necessary for p [Scruton] |
Full Idea: If p entails q, then p is sufficient for q, and q is necessary for p. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 15.7) |
224 | When questions are doubtful we should concentrate not on objects but on ideas of the intellect [Plato] |
Full Idea: Doubtful questions should not be discussed in terms of visible objects or in relation to them, but only with reference to ideas conceived by the intellect. | |
From: Plato (Parmenides [c.364 BCE], 135e) |
232 | Opposites are as unlike as possible [Plato] |
Full Idea: Opposites are as unlike as possible. | |
From: Plato (Parmenides [c.364 BCE], 159a) |
8937 | Plato's 'Parmenides' is the greatest artistic achievement of the ancient dialectic [Hegel on Plato] |
Full Idea: Plato's 'Parmenides' is the greatest artistic achievement of the ancient dialectic. | |
From: comment on Plato (Parmenides [c.364 BCE]) by Georg W.F.Hegel - Phenomenology of Spirit Pref 71 | |
A reaction: It is a long way from the analytic tradition of philosophy to be singling out a classic text for its 'artistic' achievement. Eventually we may even look back on, say, Kripke's 'Naming and Necessity' and see it in that light. |
3894 | We may define 'good' correctly, but then ask whether the application of the definition is good [Scruton] |
Full Idea: The 'open question' argument is clearly invalid. A question remains open just so long as our ignorance permits. …It may be an open question whether promoting happiness is good, even though this is what 'good' means. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 20.1) | |
A reaction: A nice objection. Like small children, we can keep asking questions forever. Whether there is a question to be asked about a thing is not a property of that thing, but of us who ask it. |
3883 | A true proposition is consistent with every other true proposition [Scruton] |
Full Idea: A true proposition is consistent with every other true proposition: no truth is contradicted by another. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 9.1) | |
A reaction: Interesting. It resembles the rule that if you always tell the truth you don't need to remember what you said. Close to the heart of the concept of truth. Coherence and correspondence. |
3884 | The pragmatist does not really have a theory of truth [Scruton] |
Full Idea: The pragmatist does not really have a theory of truth. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 9.4) |
17833 | The first-order ZF axiomatisation is highly non-categorical [Hallett,M] |
Full Idea: The first-order Sermelo-Fraenkel axiomatisation is highly non-categorical. | |
From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1213) |
17834 | Non-categoricity reveals a sort of incompleteness, with sets existing that the axioms don't reveal [Hallett,M] |
Full Idea: The non-categoricity of the axioms which Zermelo demonstrates reveals an incompleteness of a sort, ....for this seems to show that there will always be a set (indeed, an unending sequence) that the basic axioms are incapable of revealing to be sets. | |
From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1215) | |
A reaction: Hallett says the incompleteness concerning Zermelo was the (transfinitely) indefinite iterability of the power set operation (which is what drives the 'iterative conception' of sets). |
17837 | Zermelo allows ur-elements, to enable the widespread application of set-theory [Hallett,M] |
Full Idea: Unlike earlier writers (such as Fraenkel), Zermelo clearly allows that there might be ur-elements (that is, objects other than the empty set, which have no members). Indeed he sees in this the possibility of widespread application of set-theory. | |
From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1217) |
13986 | Plato found antinomies in ideas, Kant in space and time, and Bradley in relations [Plato, by Ryle] |
Full Idea: Plato (in 'Parmenides') shows that the theory that 'Eide' are substances, and Kant that space and time are substances, and Bradley that relations are substances, all lead to aninomies. | |
From: report of Plato (Parmenides [c.364 BCE]) by Gilbert Ryle - Are there propositions? 'Objections' |
14150 | Plato's 'Parmenides' is perhaps the best collection of antinomies ever made [Russell on Plato] |
Full Idea: Plato's 'Parmenides' is perhaps the best collection of antinomies ever made. | |
From: comment on Plato (Parmenides [c.364 BCE]) by Bertrand Russell - The Principles of Mathematics §337 |
3907 | Could you be intellectually acquainted with numbers, but unable to count objects? [Scruton] |
Full Idea: Could someone have a perfect intellectual acquaintance with numbers, but be incapable of counting a flock of sheep? | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 26.6) |
17836 | The General Continuum Hypothesis and its negation are both consistent with ZF [Hallett,M] |
Full Idea: In 1938, Gödel showed that ZF plus the General Continuum Hypothesis is consistent if ZF is. Cohen showed that ZF and not-GCH is also consistent if ZF is, which finally shows that neither GCH nor ¬GCH can be proved from ZF itself. | |
From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1217) |
16150 | One is, so numbers exist, so endless numbers exist, and each one must partake of being [Plato] |
Full Idea: If one is, there must also necessarily be number - Necessarily - But if there is number, there would be many, and an unlimited multitude of beings. ..So if all partakes of being, each part of number would also partake of it. | |
From: Plato (Parmenides [c.364 BCE], 144a) | |
A reaction: This seems to commit to numbers having being, then to too many numbers, and hence to too much being - but without backing down and wondering whether numbers had being after all. Aristotle disagreed. |
3908 | If maths contains unprovable truths, then maths cannot be reduced to a set of proofs [Scruton] |
Full Idea: If there can be unprovable truths of mathematics, then mathematics cannot be reduced to the proofs whereby we construct it. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 26.7) |
229 | The one was and is and will be and was becoming and is becoming and will become [Plato] |
Full Idea: The one was and is and will be and was becoming and is becoming and will become. | |
From: Plato (Parmenides [c.364 BCE], 155d) | |
A reaction: This seems to be rhetorical, rather a precise theory, given that the One is said to be eternal and unchanging. The One is not just what we call 'reality'. |
21821 | Plato's Parmenides has a three-part theory, of Primal One, a One-Many, and a One-and-Many [Plato, by Plotinus] |
Full Idea: The Platonic Parmenides is more exact [than Parmenides himself]; the distinction is made between the Primal One, a strictly pure Unity, and a secondary One which is a One-Many, and a third which is a One-and-Many. | |
From: report of Plato (Parmenides [c.364 BCE]) by Plotinus - The Enneads 5.1.08 | |
A reaction: Plotinus approves of this three-part theory. Parmenides has the problem that the highest Being contains no movement. By placing the One outside Being you can give it powers which an existent thing cannot have. Cf the concept of God. |
221 | Absolute ideas, such as the Good and the Beautiful, cannot be known by us [Plato] |
Full Idea: The absolute good and the beautiful and all which we conceive to be absolute ideas are unknown to us. | |
From: Plato (Parmenides [c.364 BCE], 134c) | |
A reaction: These seems to thoroughly pre-empt Plato's Theory of Forms a century before he created it. Which shows (as Simone Weil says) that Plato was just part of a long tradition. |
3906 | If possible worlds are needed to define properties, maybe we should abandon properties [Scruton] |
Full Idea: If the only way of defining properties involves quantifying over possible worlds, this could be taken as another reason for abandoning properties altogether. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 26.4) |
223 | If you deny that each thing always stays the same, you destroy the possibility of discussion [Plato] |
Full Idea: If a person denies that the idea of each thing is always the same, he will utterly destroy the power of carrying on discussion. | |
From: Plato (Parmenides [c.364 BCE], 135c) |
227 | You must always mean the same thing when you utter the same name [Plato] |
Full Idea: You must always mean the same thing when you utter the same name. | |
From: Plato (Parmenides [c.364 BCE], 147d) |
211 | If admirable things have Forms, maybe everything else does as well [Plato] |
Full Idea: It is troubling that if admirable things have abstract ideas, then perhaps everything else must have ideas as well. | |
From: Plato (Parmenides [c.364 BCE], 130d) |
220 | The concept of a master includes the concept of a slave [Plato] |
Full Idea: Mastership in the abstract is mastership of slavery in the abstract. | |
From: Plato (Parmenides [c.364 BCE], 133e) |
16151 | Plato moves from Forms to a theory of genera and principles in his later work [Plato, by Frede,M] |
Full Idea: It seems to me that Plato in the later dialogues, beginning with the second half of 'Parmenides', wants to substitute a theory of genera and theory of principles that constitute these genera for the earlier theory of forms. | |
From: report of Plato (Parmenides [c.364 BCE]) by Michael Frede - Title, Unity, Authenticity of the 'Categories' V | |
A reaction: My theory is that the later Plato came under the influence of the brilliant young Aristotle, and this idea is a symptom of it. The theory of 'principles' sounds like hylomorphism to me. |
210 | It would be absurd to think there were abstract Forms for vile things like hair, mud and dirt [Plato] |
Full Idea: Are there abstract ideas for such things as hair, mud and dirt, which are particularly vile and worthless? That would be quite absurd. | |
From: Plato (Parmenides [c.364 BCE], 130d) |
219 | If absolute ideas existed in us, they would cease to be absolute [Plato] |
Full Idea: None of the absolute ideas exists in us, because then it would no longer be absolute. | |
From: Plato (Parmenides [c.364 BCE], 133c) |
228 | Greatness and smallness must exist, to be opposed to one another, and come into being in things [Plato] |
Full Idea: These two ideas, greatness and smallness, exist, do they not? For if they did not exist, they could not be opposites of one another, and could not come into being in things. | |
From: Plato (Parmenides [c.364 BCE], 149e) |
215 | If things partake of ideas, this implies either that everything thinks, or that everything actually is thought [Plato] |
Full Idea: If all things partake of ideas, must either everything be made of thoughts and everything thinks, or everything is thought, and so can't think? | |
From: Plato (Parmenides [c.364 BCE], 132c) |
212 | The whole idea of each Form must be found in each thing which participates in it [Plato] |
Full Idea: The whole idea of each form (of beauty, justice etc) must be found in each thing which participates in it. | |
From: Plato (Parmenides [c.364 BCE], 131a) |
213 | Each idea is in all its participants at once, just as daytime is a unity but in many separate places at once [Plato] |
Full Idea: Just as day is in many places at once, but not separated from itself, so each idea might be in all its participants at once. | |
From: Plato (Parmenides [c.364 BCE], 131b) |
216 | If things are made alike by participating in something, that thing will be the absolute idea [Plato] |
Full Idea: That by participation in which like things are made like, will be the absolute idea, will it not? | |
From: Plato (Parmenides [c.364 BCE], 132e) |
218 | Participation is not by means of similarity, so we are looking for some other method of participation [Plato] |
Full Idea: Participation is not by means of likeness, so we must seek some other method of participation. | |
From: Plato (Parmenides [c.364 BCE], 133a) |
217 | Nothing can be like an absolute idea, because a third idea intervenes to make them alike (leading to a regress) [Plato] |
Full Idea: It is impossible for anything to be like an absolute idea, because a third idea will appear to make them alike, and if that is like anything, it will lead to another idea, and so on. | |
From: Plato (Parmenides [c.364 BCE], 133a) |
214 | If absolute greatness and great things are seen as the same, another thing appears which makes them seem great [Plato] |
Full Idea: If you regard the absolute great and the many great things in the same way, will not another appear beyond, by which all these must appear to be great? | |
From: Plato (Parmenides [c.364 BCE], 132a) |
15851 | Parts must belong to a created thing with a distinct form [Plato] |
Full Idea: The part would not be the part of many things or all, but of some one character ['ideas'] and of some one thing, which we call a 'whole', since it has come to be one complete [perfected] thing composed [created] of all. | |
From: Plato (Parmenides [c.364 BCE], 157d) | |
A reaction: A serious shot by Plato at what identity is. Harte quotes it (125) and shows that 'character' is Gk 'idea', and 'composed' will translate as 'created'. 'Form' links this Platonic passage to Aristotle's hylomorphism. |
15846 | In Parmenides, if composition is identity, a whole is nothing more than its parts [Plato, by Harte,V] |
Full Idea: At the heart of the 'Parmenides' puzzles about composition is the thesis that composition is identity. Considered thus, a whole adds nothing to an ontology that already includes its parts | |
From: report of Plato (Parmenides [c.364 BCE]) by Verity Harte - Plato on Parts and Wholes 2.5 | |
A reaction: There has to be more to a unified identity that mere proximity of the parts. When do parts come together, and when do they actually 'compose' something? |
15849 | Plato says only a one has parts, and a many does not [Plato, by Harte,V] |
Full Idea: In 'Parmenides' it is argued that a part cannot be part of a many, but must be part of something one. | |
From: report of Plato (Parmenides [c.364 BCE], 157c) by Verity Harte - Plato on Parts and Wholes 3.2 | |
A reaction: This looks like the right way to go with the term 'part'. We presuppose a unity before we even talk of its parts, so we can't get into contradictions and paradoxes about their relationships. |
15850 | Anything which has parts must be one thing, and parts are of a one, not of a many [Plato] |
Full Idea: The whole of which the parts are parts must be one thing composed of many; for each of the parts must be part, not of a many, but of a whole. | |
From: Plato (Parmenides [c.364 BCE], 157c) | |
A reaction: This is a key move of metaphysics, and we should hang on to it. The other way madness lies. |
13259 | It seems that the One must be composed of parts, which contradicts its being one [Plato] |
Full Idea: The One must be composed of parts, both being a whole and having parts. So on both grounds the One would thus be many and not one. But it must be not many, but one. So if the One will be one, it will neither be a whole, nor have parts. | |
From: Plato (Parmenides [c.364 BCE], 137c09), quoted by Kathrin Koslicki - The Structure of Objects 5.2 | |
A reaction: This is the starting point for Plato's metaphysical discussion of objects. It seems to begin a line of thought which is completed by Aristotle, surmising that only an essential structure can bestow identity on a bunch of parts. |
15847 | Two things relate either as same or different, or part of a whole, or the whole of the part [Plato] |
Full Idea: Everything is surely related to everything as follows: either it is the same or different; or, if it is not the same or different, it would be related as part to whole or as whole to part. | |
From: Plato (Parmenides [c.364 BCE], 146b) | |
A reaction: This strikes me as a really helpful first step in trying to analyse the nature of identity. Two things are either two or (actually) one, or related mereologically. |
3888 | Hume assumes that necessity can only be de dicto, not de re [Scruton] |
Full Idea: It was one of the assumptions of Hume's empiricism that all necessities are de dicto: i.e. they are artefacts of language. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 13.5) |
3903 | The conceivable can't be a test of the possible, if there are things which are possible but inconceivable [Scruton] |
Full Idea: If there are things which are possible but inconceivable, we must abandon the view, which has had a considerable following since Descartes, that the conceivable is a test of the possible. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 25) |
3897 | Epistemology is about the justification of belief, not the definition of knowledge [Scruton] |
Full Idea: In my view the concept of knowledge is of no very great interest in epistemology, which actually concerns the justification of belief. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 22) | |
A reaction: I think this is an excellent thought. I see knowledge as slippery, and partially contextual, and I don't care whether someone precisely 'knows' something. I just want to know why they believe it. |
3881 | In the Cogito argument consciousness develops into self-consciousness [Scruton] |
Full Idea: In the course of the argument the first person has acquired a character; he is not merely conscious, but self-conscious. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 4) |
3887 | Maybe our knowledge of truth and causation is synthetic a priori [Scruton] |
Full Idea: 'Every event has a cause' and 'truth is correspondence to facts' are candidates for being synthetic a priori knowledge. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 13.2) |
3901 | Touch only seems to reveal primary qualities [Scruton] |
Full Idea: Touch seems to deliver a purely primary-quality account of the world. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 24) | |
A reaction: Interesting, though a little over-confident. It seems occasionally possible for touch to be an illusion. |
3885 | We only conceive of primary qualities as attached to secondary qualities [Scruton] |
Full Idea: Bradley argued that we cannot conceive of primary qualities except as attached to secondary qualities. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 10.1) |
3910 | If primary and secondary qualities are distinct, what has the secondary qualities? [Scruton] |
Full Idea: If primary and secondary qualities are distinct, what do secondary qualities inhere in? | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], Ch.10 n) | |
A reaction: What is the problem? A pin causes me pain, but I know the pain isn't in the pin. It is the same with colour. It is a mental property, if you like, triggered by a wavelength of radiation. |
3899 | The representational theory says perceptual states are intentional states [Scruton] |
Full Idea: The representational theory is the unsurprising view that perceptual states are intentional, like beliefs, emotions and desires. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 23.3) |
3898 | My belief that it will rain tomorrow can't be caused by its raining tomorrow [Scruton] |
Full Idea: It is impossible that my present belief that it will rain tomorrow is caused by its raining tomorrow. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 22.4) | |
A reaction: This doesn't demolish a causal account of belief. It would be very surprising if I were to believe it was going to rain tomorrow for no cause whatsoever. That would be irrational. |
3880 | Logical positivism avoids scepticism, by closing the gap between evidence and conclusion [Scruton] |
Full Idea: If the evidence for p is q, and that is the only evidence there is or can be, then 'p' means q. Hence there is no gap between evidence and conclusion, and the sceptical problem does not arise. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 3.2) |
3878 | Why should you believe someone who says there are no truths? [Scruton] |
Full Idea: A writer who says that there are no truths, or that all truth is 'merely relative', is asking you not to believe him. So don't. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 1.1) |
3892 | Every event having a cause, and every event being determined by its cause, are not the same [Scruton] |
Full Idea: To say that every event has a cause is one thing; to say that every event is determined by its cause is quite another thing. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 17.1) |
3911 | The very concept of a substance denies the possibility of mutual interaction and dependence [Scruton] |
Full Idea: It is often held to be a consequence of the rationalist conception of substance, that separate substances cannot interact (since causal interaction is a form of mutual dependence). | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], Ch.16 n) | |
A reaction: Yes, substances seem incapable of interaction, just as Leibniz argues that perfections could never interact. They are too pure. |
3882 | Wittgenstein makes it impossible to build foundations from something that is totally private [Scruton] |
Full Idea: Wittgenstein's point is that if I search for foundations in what can only be known to me, then the belief that I have discovered those foundations will also fall victim to Descartes' demon. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 5.3) | |
A reaction: Why should foundations based in wider society or a language community fare any better? Getting a lot of people to agree won't trouble the demon too much. Flat earthers. |
3896 | Any social theory of morality has the problem of the 'free rider', who only pretends to join in [Scruton] |
Full Idea: Any attempt to provide a social justification of morality runs the risk of the 'free rider' - one who pretends to play the game in order to enjoy the fruits of it. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 20.6) |
3886 | Membership is the greatest source of obligation [Scruton] |
Full Idea: Membership is the greatest source of obligation. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 11.2) | |
A reaction: An interesting and rather Aristotelian idea. The alternative is individual debt or obligation. |
3895 | The categorical imperative is not just individual, but can be used for negotiations between strangers [Scruton] |
Full Idea: The categorical imperative is also an instrument of negotiation and compromise between strangers, through which they can rise out of enmity and confront each other as equals. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 20.6) |
222 | Only a great person can understand the essence of things, and an even greater person can teach it [Plato] |
Full Idea: Only a man of very great natural gifts will be able to understand that everything has a class and absolute essence, and an even more wonderful man can teach this. | |
From: Plato (Parmenides [c.364 BCE], 135a) |
225 | The unlimited has no shape and is endless [Plato] |
Full Idea: The unlimited partakes neither of the round nor of the straight, because it has no ends nor edges. | |
From: Plato (Parmenides [c.364 BCE], 137e) |
233 | Some things do not partake of the One [Plato] |
Full Idea: The others cannot partake of the one in any way; they can neither partake of it nor of the whole. | |
From: Plato (Parmenides [c.364 BCE], 159d) | |
A reaction: Compare Idea 231 |
2062 | The only movement possible for the One is in space or in alteration [Plato] |
Full Idea: If the One moves it either moves spatially or it is altered, since these are the only motions. | |
From: Plato (Parmenides [c.364 BCE], 138b) |
231 | Everything partakes of the One in some way [Plato] |
Full Idea: The others are not altogether deprived of the one, for they partake of it in some way. | |
From: Plato (Parmenides [c.364 BCE], 157c) | |
A reaction: Compare Idea 233. |
3890 | 'Cause' used to just mean any valid explanation [Scruton] |
Full Idea: Traditionally (before Leibniz and Spinoza) the world 'cause' signified any valid explanation. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 14) |
3904 | Measuring space requires no movement while I do it [Scruton] |
Full Idea: I can measure the length of something only if I know that it has not moved between the moment when I locate one end of it and the moment when I locate the other. | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 25.3) | |
A reaction: A nice example of how even simple propositions have many presuppositions. |
234 | We couldn't discuss the non-existence of the One without knowledge of it [Plato] |
Full Idea: There must be knowledge of the one, or else not even the meaning of the words 'if the one does not exist' would be known. | |
From: Plato (Parmenides [c.364 BCE], 160d) |
3905 | 'Existence' is not a predicate of 'man', but of the concept of man, saying it has at least one instance [Scruton] |
Full Idea: When I say that a man exists, Frege argues, I do not predicate existence of a man, but rather of the concept man: I say the concept has at least one instance (and existence is a predicate of predicates). | |
From: Roger Scruton (Modern Philosophy:introduction and survey [1994], 26.2) |