109 ideas
| 22733 | Epicurus accepted God in his popular works, but not in his writings on nature [Epicurus, by Sext.Empiricus] |
| Full Idea: Epicurus in his popular exposition allows the existence of God, but in expounding the real nature of things he does not allow it. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Sextus Empiricus - Against the Physicists (two books) I.58 | |
| A reaction: Plato and Aristotle also distinguished their esoteric from their exoteric writings, but this is an indication that thei popular works may always have presented safer doctrines. |
| 13291 | Slavery to philosophy brings true freedom [Epicurus] |
| Full Idea: To win true freedom you must be a slave to philosophy. | |
| From: Epicurus (fragments/reports [c.289 BCE]), quoted by Seneca the Younger - Letters from a Stoic 008 | |
| A reaction: A lovely idea. It is one thing to free the body, or to free one's social situation, but the challenge to 'free your mind' is either romantic nonsense or totally baffling, apart from the suggestion offered here. Reason is freedom. Very Kantian. |
| 22758 | Philosophy aims at a happy life, through argument and discussion [Epicurus] |
| Full Idea: Philosophy is an activity which secures the happy life by arguments and discussions. | |
| From: Epicurus (fragments/reports [c.289 BCE]), quoted by Sextus Empiricus - Against the Ethicists (one book) VI.169 | |
| A reaction: Presumably this aims at the happiness of the participant. Universal happiness would need to be much more political. If this is your aim then you can't just follow the winds of the argument, but must channel it towards happiness. No nasty truths? |
| 14523 | We should come to philosophy free from any taint of culture [Epicurus] |
| Full Idea: I congratulate you, sir, because you have come to philosophy free of any taint of culture. | |
| From: Epicurus (fragments/reports [c.289 BCE]) | |
| A reaction: [source: Athenaeus, 'Deipnosophists' 13 588b] No one nowadays thinks such an aspiration remotely possible, not least because the culture is embedded in your native language, but I find the idea very appealing. |
| 22240 | The aim of medicine is removal of sickness, and philosophy similarly removes our affections [Epicurus] |
| Full Idea: Just as there is no benefit to medicine if it does not heal the sicknesses [nosos] of bodies, so too there is none to philosophy unless it expels that affections of the soul. | |
| From: Epicurus (fragments/reports [c.289 BCE], fr 221), quoted by James Allen - Soul's Virtue and the Health of the Body p.78 | |
| A reaction: This sounds rather Buddhist, if the only route to happiness is to suppress the emotions. Epicurus probably refers to the more extreme desires, which only lead to harm. Galen quotes Chrysippus as endorsing this idea (see footnote 5). |
| 1484 | We should say nothing of the whole if our contact is with the parts [Epicurus, by Plutarch] |
| Full Idea: We should make no assertion about the whole when our contact is with the parts. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Plutarch - 74: Reply to Colotes 1109e |
| 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. |
| 2670 | Epicurus despises and laughs at the whole of dialectic [Epicurus, by Cicero] |
| Full Idea: Epicurus despises and laughs at the whole of dialectic. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by M. Tullius Cicero - Academica II.30.97 |
| 9847 | A contextual definition permits the elimination of the expression by a substitution [Dummett] |
| Full Idea: The standard sense of a 'contextual definition' permits the eliminating of the defined expression, by transforming any sentence containing it into an equivalent one not containing it. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.11) | |
| A reaction: So the whole definition might be eliminated by a single word, which is not equivalent to the target word, which is embedded in the original expression. Clearly contextual definitions have some problems |
| 9820 | In classical logic, logical truths are valid formulas; in higher-order logics they are purely logical [Dummett] |
| Full Idea: For sentential or first-order logic, the logical truths are represented by valid formulas; in higher-order logics, by sentences formulated in purely logical terms. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch. 3) |
| 21668 | Epicurus rejected excluded middle, because accepting it for events is fatalistic [Epicurus, by Cicero] |
| Full Idea: Epicurus said that not every proposition is either true or false. ...Epicurus was afraid that if he admits that every proposition is true or false he will also have to admit that all events are caused by fate (if they are so from all eternity). | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by M. Tullius Cicero - On Fate ('De fato') 10.21 | |
| A reaction: Epicurus proposed his 'swerve' in the movements of atoms to avoid this fatalism. Epicurus is agreeing with Aristotle, who did not accept excluded middle for a future contingent sea-fight. |
| 21676 | Epicureans say disjunctions can be true whiile the disjuncts are not true [Epicurus, by Cicero] |
| Full Idea: Epicureans make the impudent assertion that disjunctions consisting of contrary propositions are true, but that the statements contained in the propositions are neither of them true. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by M. Tullius Cicero - On Fate ('De fato') 16.36 | |
| A reaction: Is that 'it is definitely one or the other, but we haven't a clue which one'? Seems to fit speculations about Goldbach's Conjecture. It doesn't sound terribly impudent to me. Or is it the crazy 'It's definitely one of them, but it's neither of them'? |
| 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 |
| 9896 | A prime number is one which is measured by a unit alone [Dummett] |
| Full Idea: A prime number is one which is measured by a unit alone. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], 7 Def 11) | |
| A reaction: We might say that the only way of 'reaching' or 'constructing' a prime is by incrementing by one till you reach it. That seems a pretty good definition. 64, for example, can be reached by a large number of different routes. |
| 18255 | Addition of quantities is prior to ordering, as shown in cyclic domains like angles [Dummett] |
| Full Idea: It is essential to a quantitative domain of any kind that there should be an operation of adding its elements; that this is more fundamental thaat that they should be linearly ordered by magnitude is apparent from cyclic domains like that of angles. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], 22 'Quantit') |
| 9895 | A number is a multitude composed of units [Dummett] |
| Full Idea: A number is a multitude composed of units. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], 7 Def 2) | |
| A reaction: This is outdated by the assumption that 0 and 1 are also numbers, but if we say one is really just the 'unit' which is preliminary to numbers, and 0 is as bogus a number as i is, we might stick with the original Greek distinction. |
| 9852 | We understand 'there are as many nuts as apples' as easily by pairing them as by counting them [Dummett] |
| Full Idea: A child understands 'there are just as many nuts as apples' as easily by pairing them off as by counting them. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.12) | |
| A reaction: I find it very intriguing that you could know that two sets have the same number, without knowing any numbers. Is it like knowing two foreigners spoke the same words, without understanding them? Or is 'equinumerous' conceptually prior to 'number'? |
| 9829 | The identity of a number may be fixed by something outside structure - by counting [Dummett] |
| Full Idea: The identity of a mathematical object may sometimes be fixed by its relation to what lies outside the structure to which it belongs. It is more fundamental to '3' that if certain objects are counted, there are three of them. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch. 5) | |
| A reaction: This strikes me as Dummett being pushed (by his dislike of the purely abstract picture given by structuralism) back to a rather empiricist and physical view of numbers, though he would totally deny that. |
| 9828 | Numbers aren't fixed by position in a structure; it won't tell you whether to start with 0 or 1 [Dummett] |
| Full Idea: The number 0 is not differentiated from 1 by its position in a progression, otherwise there would be no difference between starting with 0 and starting with 1. That is enough to show that numbers are not identifiable just as positions in structures. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch. 5) | |
| A reaction: This sounds conclusive, but doesn't feel right. If numbers are a structure, then where you 'start' seems unimportant. Where do you 'start' in St Paul's Cathedral? Starting sounds like a constructivist concept for number theory. |
| 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. |
| 9876 | Set theory isn't part of logic, and why reduce to something more complex? [Dummett] |
| Full Idea: The two frequent modern objects to logicism are that set theory is not part of logic, or that it is of no interest to 'reduce' a mathematical theory to another, more complex, one. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.18) | |
| A reaction: Dummett says these are irrelevant (see context). The first one seems a good objection. The second one less so, because whether something is 'complex' is a quite different issue from whether it is ontologically more fundamental. |
| 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) |
| 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. |
| 9884 | The distinction of concrete/abstract, or actual/non-actual, is a scale, not a dichotomy [Dummett] |
| Full Idea: The distinction between concrete and abstract objects, or Frege's corresponding distinction between actual and non-actual objects, is not a sharp dichotomy, but resembles a scale upon which objects occupy a range of positions. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.18) | |
| A reaction: This might seem right if you live (as Dummett chooses to) in the fog of language, but it surely can't be right if you think about reality. Is the Equator supposed to be near the middle of his scale? Either there is an equator, or there isn't. |
| 9869 | Realism is just the application of two-valued semantics to sentences [Dummett] |
| Full Idea: Fully fledged realism depends on - indeed, may be identified with - an undiluted application to sentences of the relevant kind of straightforwards two-valued semantics. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.15) | |
| A reaction: This is the sort of account you get from a whole-heartedly linguistic philosopher. Personally I would say that Dummett has got it precisely the wrong way round: I adopt a two-valued semantics because my metaphysics is realist. |
| 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) |
| 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) |
| 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) |
| 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) |
| 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) |
| 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) |
| 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) |
| 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. |
| 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) |
| 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) |
| 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) |
| 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) |
| 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) |
| 9880 | Nominalism assumes unmediated mental contact with objects [Dummett] |
| Full Idea: The nominalist superstition is based ultimately on the myth of the unmediated presentation of genuine concrete objects to the mind. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.18) | |
| A reaction: Personally I am inclined to favour nominalism and a representative theory of perception, which acknowledges some 'mediation', but of a non-linguistic form. Any good theory here had better include animals, which seem to form concepts. |
| 9885 | The existence of abstract objects is a pseudo-problem [Dummett] |
| Full Idea: The existence of abstract objects is a pseudo-problem. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.18) | |
| A reaction: This remark follows after Idea 9884, which says the abstract/concrete distinction is a sliding scale. Personally I take the distinction to be fairly sharp, and it is therefore probably the single most important problem in the whole of human thought. |
| 9858 | Abstract objects nowadays are those which are objective but not actual [Dummett] |
| Full Idea: Objects which are objective but not actual are precisely what are now called abstract objects. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.15) | |
| A reaction: Why can there not be subjective abstract objects? 'My favourites are x, y and z'. 'I'll decide later what my favourites are'. 'I only buy my favourites - nothing else'. |
| 9859 | It is absurd to deny the Equator, on the grounds that it lacks causal powers [Dummett] |
| Full Idea: If someone argued that assuming the existence of the Equator explains nothing, and it has no causal powers, so everything would be the same if it didn't exist, so we needn't accept its existence, we should gape at the crudity of the misunderstanding. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.15) | |
| A reaction: Not me. I would gape if someone argued that latitude 55° 14' (and an infinity of other lines) exists for the same reasons (whatever they may be) that the Equator exists. A mode of description can't create an object. |
| 9860 | 'We've crossed the Equator' has truth-conditions, so accept the Equator - and it's an object [Dummett] |
| Full Idea: 'We've crossed the Equator' is judged true if we are nearer the other Pole, so it not for philosophers to deny that the Earth has an equator, and we see that the Equator is not a concept or relation or function, so it must be classified as an object. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.15) | |
| A reaction: A lovely example of linguistic philosophy in action (and so much the worse for that, I would say). A useful label here, I suggest (unoriginally, I think), is that we should label such an item a 'semantic object', rather than a real object in our ontology. |
| 9872 | Abstract objects need the context principle, since they can't be encountered directly [Dummett] |
| Full Idea: To recognise that there is no objection in principle to abstract objects requires acknowledgement that some form of the context principle is correct, since abstract objects can neither be encountered nor presented. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.16) | |
| A reaction: I take this to be an immensely important idea. I consider myself to be a philosopher of thought rather than a philosopher of language (Dummett's distinction, he being one of the latter). Thought connects to the world, but does it connect to abstracta? |
| 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. |
| 9848 | Content is replaceable if identical, so replaceability can't define identity [Dummett, by Dummett] |
| Full Idea: Husserl says the only ground for assuming the replaceability of one content by another is their identity; we are therefore not entitled to define their identity as consisting in their replaceability. | |
| From: report of Michael Dummett (Frege philosophy of mathematics [1991]) by Michael Dummett - Frege philosophy of mathematics Ch.12 | |
| A reaction: This is a direct challenge to Frege. Tricky to arbitrate, as it is an issue of conceptual priority. My intuition is with Husserl, but maybe the two are just benignly inerdefinable. |
| 9842 | Frege introduced criteria for identity, but thought defining identity was circular [Dummett] |
| Full Idea: In his middle period Frege rated identity indefinable, on the ground that every definition must take the form of an identity-statement. Frege introduced the notion of criterion of identity, which has been widely used by analytical philosophers. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.10) | |
| A reaction: The objection that attempts to define identity would be circular sounds quite plausible. It sounds right to seek a criterion for type-identity (in shared properties or predicates), but token-identity looks too fundamental to give clear criteria. |
| 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. |
| 1823 | We can't seek for things if we have no idea of them [Epicurus, by Diog. Laertius] |
| Full Idea: We could not seek for anything if we had not some notion of it. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 10.21 |
| 1824 | To name something, you must already have an idea of what it is [Epicurus, by Diog. Laertius] |
| Full Idea: We could not give names to things, if we had not a preliminary notion of what the things were. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 10.21 |
| 5949 | Epicurus says colours are relative to the eye, not intrinsic to bodies [Epicurus, by Plutarch] |
| Full Idea: Epicurus says that colours are not intrinsic to bodies but a result of certain arrangements and positions relative to the eye, which implies that body is no more colourless than coloured. | |
| From: report of Epicurus (fragments/reports [c.289 BCE], Fr 30) by Plutarch - 74: Reply to Colotes §1110 | |
| A reaction: This seems to me such a self-evident truth that I am puzzled as to why anyone would claim that colours are real features of bodies. Epicurus points out that entering a dark room we see no colour, but then colour appears after a while. |
| 1821 | Sensations cannot be judged, because similar sensations have equal value, and different ones have nothing in common [Epicurus, by Diog. Laertius] |
| Full Idea: Sensation is out of reach of control, because one sensation cannot judge another which resembles itself, as they have equal value, and different sensations have different objects. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 10.20 | |
| A reaction: Scepticism about the possibility of purely empirical knowledge; an interesting comment on the question of whether perceptions contain any intrinsic knowledge. |
| 1820 | The criteria of truth are senses, preconceptions and passions [Epicurus, by Diog. Laertius] |
| Full Idea: The criteria of truth are the senses, the preconceptions, and the passions. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 10.20 |
| 1822 | Reason can't judge senses, as it is based on them [Epicurus, by Diog. Laertius] |
| Full Idea: Reason cannot judge the senses, because it is based on them. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 10.20 |
| 4549 | Epicurus denied knowledge in order to retain morality or hedonism as the highest values [Nietzsche on Epicurus] |
| Full Idea: Epicurus denied the possibility of knowledge in order to retain moral (or hedonistic) values as the highest values. | |
| From: comment on Epicurus (fragments/reports [c.289 BCE]) by Friedrich Nietzsche - The Will to Power (notebooks) §578 | |
| A reaction: The history of philosophy suggests that this dichotomy is unnecessary. Dogmatist place a high value on multitudes of things. |
| 2668 | Epicurus says if one of a man's senses ever lies, none of his senses should ever be believed [Epicurus, by Cicero] |
| Full Idea: Epicurus says that if one sense has told a lie once in a man's life, no sense must ever be believed. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by M. Tullius Cicero - Academica II.25.79 |
| 1482 | If two people disagree over taste, who is right? [Epicurus, by Plutarch] |
| Full Idea: If one person says the wine is dry and the other that it is sweet, and neither errs in his sensation, how is the wine any more dry than sweet? | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Plutarch - 74: Reply to Colotes 1109b |
| 1483 | Bath water is too hot for some, too cold for others [Epicurus, by Plutarch] |
| Full Idea: In the very same bath some treat the water as too hot, others as too cold. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Plutarch - 74: Reply to Colotes 1109b |
| 1487 | When entering a dark room it is colourless, but colour gradually appears [Epicurus] |
| Full Idea: On entering a dark room we see no colour, but do so after waiting a short time. | |
| From: Epicurus (fragments/reports [c.289 BCE]), quoted by Plutarch - 74: Reply to Colotes 1110d |
| 14526 | The rational soul is in the chest, and the non-rational soul is spread through the body [Epicurus] |
| Full Idea: Democritus and Epicurus say the soul has two parts, one which is rational and is situated in the chest area, and the other which is non-rational and is spread throughout the entire compound of the body | |
| From: Epicurus (fragments/reports [c.289 BCE]) | |
| A reaction: [source Aetius 4.4.6] |
| 6035 | Soul is made of four stuffs, giving warmth, rest, motion and perception [Epicurus, by Aetius] |
| Full Idea: Epicurus says the soul is a blend of fiery stuff (for bodily warmth), airy stuff (rest), breath (motion), and a nameless stuff (sense-perception). | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Aetius - fragments/reports 4.3.11 | |
| A reaction: Obviously Epicurus thought the four stuffs were different combinations of atoms, rather than being elements. Is there no stuff which gives reason? Reason must reduce to motion, presumably. |
| 6018 | Epicurus was the first to see the free will problem, and he was a libertarian [Epicurus, by Long/Sedley] |
| Full Idea: By posing the problem of determinism, Epicurus became arguably the first philosopher to recognise the philosophical centrality of what we call the Free Will Question. His strongly libertarian approach is strongly contrasted with Stoic determinism. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by AA Long / DN Sedley - Hellenic Philosophers commentary | |
| A reaction: Epicurus introduced the rather dubious 'swerve' of the atoms to make room for free will. It seems to me more consistent to stick with the determinism of Democritus. Zeno became a determinist in reaction to Epicurus. |
| 20922 | Epicurus showed that the swerve can give free motion in the atoms [Epicurus, by Diogenes of Oen.] |
| Full Idea: There is a free motion in the atoms, which Democritus did not discover, but which Epicurus brought to light, and which consists in a swerve, as he demonstrated on the basis of what is seen to be the case? | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Diogenes (Oen) - Wall inscription 54.II-III | |
| A reaction: I presume the last bit means that we see that we have freedom of choice, and infer the swerve in the atoms as the only possible explanation. The worry for libertarians is, of course, who is in charge of the swerve. |
| 14516 | There is no necessity to live with necessity [Epicurus] |
| Full Idea: Necessity is a bad thing, but there is no necessity to live with necessity. | |
| From: Epicurus (fragments/reports [c.289 BCE], 9) |
| 1909 | How can pleasure or judgement occur in a heap of atoms? [Sext.Empiricus on Epicurus] |
| Full Idea: If Epicurus makes the end consist in pleasure and asserts that the soul, like all else, is composed of atoms, it is impossible to explain how in a heap of atoms there can come about pleasure, or judgement of the good. | |
| From: comment on Epicurus (fragments/reports [c.289 BCE]) by Sextus Empiricus - Outlines of Pyrrhonism III.187 | |
| A reaction: This is a nice statement of the mind-body problem. Ontologically, physics still seems to present reality as a 'heap of particles', which gives no basis for the emergence of anything as strange as consciousness. But then magnetism is pretty strange. |
| 9849 | Maybe a concept is 'prior' to another if it can be defined without the second concept [Dummett] |
| Full Idea: One powerful argument for a thesis that one notion is conceptually prior to another is the possibility of defining the first without reference to the second. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.12) | |
| A reaction: You'd better check whether you can't also define the second without reference to the first before you rank their priority. And maybe 'conceptual priority' is conceptually prior to 'definition' (i.e. definition needs a knowledge of priority). Help! |
| 9850 | An argument for conceptual priority is greater simplicity in explanation [Dummett] |
| Full Idea: An argument for conceptual priority is greater simplicity in explanation. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.12) | |
| A reaction: One might still have to decide priority between two equally simple (or complex) concepts. I begin to wonder whether 'priority' has any other than an instrumental meaning (according to which direction you wish to travel - is London before Edinburgh?). |
| 9873 | Abstract terms are acceptable as long as we know how they function linguistically [Dummett] |
| Full Idea: To recognise abstract terms as perfectly proper items of a vocabulary depends upon allowing that all that is necessary for the lawful introduction of a range of expressions into the language is a coherent account of how they are to function in sentences. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.16) | |
| A reaction: Why can't the 'coherent account' of the sentences include the fact that there must be something there for the terms to refer to? How else are we to eliminate nonsense words which obey good syntactical rules? Cf. Idea 9872. |
| 9993 | There is no reason why abstraction by equivalence classes should be called 'logical' [Dummett, by Tait] |
| Full Idea: Dummett uses the term 'logical abstraction' for the construction of the abstract objects as equivalence classes, but it is not clear why we should call this construction 'logical'. | |
| From: report of Michael Dummett (Frege philosophy of mathematics [1991]) by William W. Tait - Frege versus Cantor and Dedekind n 14 | |
| A reaction: This is a good objection, and Tait offers a much better notion of 'logical abstraction' (as involving preconditions for successful inference), in Idea 9981. |
| 9857 | We arrive at the concept 'suicide' by comparing 'Cato killed Cato' with 'Brutus killed Brutus' [Dummett] |
| Full Idea: We arrive at the concept of suicide by considering both occurrences in the sentence 'Cato killed Cato' of the proper name 'Cato' as simultaneously replaceable by another name, say 'Brutus', and so apprehending the pattern common to both sentences. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.14) | |
| A reaction: This is intended to illustrate Frege's 'logical abstraction' technique, as opposed to wicked psychological abstraction. The concept of suicide is the pattern 'x killed x'. This is a crucial example if we are to understand abstraction... |
| 9833 | To abstract from spoons (to get the same number as the forks), the spoons must be indistinguishable too [Dummett] |
| Full Idea: To get units by abstraction, units arrived at by abstraction from forks must the identical to that abstracted from spoons, with no trace of individuality. But if spoons can no longer be differentiated from forks, they can't differ from one another either. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch. 8) | |
| A reaction: [compressed] Dummett makes the point better than Frege did. Can we 'think of a fork insofar as it is countable, ignoring its other features'? What are we left thinking of? Frege says it must still be the whole fork. 'Nice fork, apart from the colour'. |
| 9836 | Fregean semantics assumes a domain articulated into individual objects [Dummett] |
| Full Idea: A Fregean semantics assumes a domain already determinately articulated into individual objects. | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], Ch. 8) | |
| A reaction: A more interesting criticism than most of Dummett's other challenges to the Frege/Davidson view. I am beginning to doubt whether the semantics and the ontology can ever be divorced from the psychology, of thought, interests, focus etc. |
| 7814 | It was Epicurus who made the question of the will's freedom central to ethics [Epicurus, by Grayling] |
| Full Idea: Epicurus was responsible for the innovatory recognition that the question of the will's freedom is central to ethics. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by A.C. Grayling - What is Good? Ch.3 | |
| A reaction: Compare Ideas 7672 and 6018. Obviously ethical action needs freedom, but the idea of a 'free will' is quite different. It is a fiction, created to give some sort of arrogant ultimate responsibility to our actions, like God. |
| 3562 | Fine things are worthless if they give no pleasure [Epicurus] |
| Full Idea: I spit on the fine and those who emptily admire it, when it doesn't make any pleasure. | |
| From: Epicurus (fragments/reports [c.289 BCE]), quoted by Julia Annas - The Morality of Happiness Ch.16 | |
| A reaction: in Athenaeus |
| 1840 | Pleasure is the chief good because it is the most natural, especially for animals [Epicurus, by Diog. Laertius] |
| Full Idea: Pleasure is the chief good, because all animals from the moment of their birth are delighted with pleasure and offended by pain by their natural instinct, without the employment of reason. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 10.29 | |
| A reaction: The highest pleasure of predators is likely to be the killing of weaker animals. What all animals do isn't much of a criterion for the natural chief good. They also breathe. |
| 1839 | Pains of the soul are worse than pains of the body, because it feels the past and future [Epicurus, by Diog. Laertius] |
| Full Idea: The pains of the soul are worst, for the flesh is only sensible of present affliction, but the soul feels the past, present and future. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 10.29 | |
| A reaction: I don't think feeling extended across time is very relevant. What matters is that pains of the soul usually endure far longer than physical suffering. |
| 1842 | Pleasures only differ in their duration and the part of the body affected [Epicurus] |
| Full Idea: If every pleasure lasted long, and affected the whole body, then there would be no difference between one pleasure and another | |
| From: Epicurus (fragments/reports [c.289 BCE]), quoted by Diogenes Laertius - Lives of Eminent Philosophers 10.31.08 | |
| A reaction: This seems to miss out on intensity, which is of great importance to most pleasure seekers. Also it is a pleasure to be alive, which is lifelong, but we barely notice it. |
| 3557 | The end for Epicurus is static pleasure [Epicurus, by Annas] |
| Full Idea: Epicurus identifies our final end with what he calls tranquillity or 'ataraxia', which is static pleasure. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Julia Annas - The Morality of Happiness Ch.7 | |
| A reaction: I don't recall any Greek ever spotting that boredom is a problem. But then they didn't have privacy, so other people always hold their attention. Maybe this is a dream of privacy. |
| 1845 | Justice has no independent existence, but arises entirely from keeping contracts [Epicurus] |
| Full Idea: Justice has no independent existence; it results from mutual contracts, and establishes itself wherever there is a mutual engagement to guard against doing or sustaining mutual injury. | |
| From: Epicurus (fragments/reports [c.289 BCE]), quoted by Diogenes Laertius - Lives of Eminent Philosophers 10.31.35 |
| 1841 | We choose virtue because of pleasure, not for its own sake [Epicurus, by Diog. Laertius] |
| Full Idea: We choose the virtues for the sake of pleasure, and not on their own account. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 10.30 |
| 1829 | A wise man would be happy even under torture [Epicurus, by Diog. Laertius] |
| Full Idea: Even if the wise man were put to the torture, he would still be happy. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 10.26 |
| 1843 | Friendship is by far the most important ingredient of a complete and happy life [Epicurus] |
| Full Idea: Of all the things which wisdom provides for the happiness of the whole life, by far the most important is the acquisition of friendship. | |
| From: Epicurus (fragments/reports [c.289 BCE]), quoted by Diogenes Laertius - Lives of Eminent Philosophers 10.31.28 |
| 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) |
| 1831 | Wise men should partake of life even if they go blind [Epicurus, by Diog. Laertius] |
| Full Idea: Even though he lose his eyes, a wise man should still partake of life. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 10.26 |
| 12044 | Only Epicurus denied purpose in nature, for the whole world, or for its parts [Epicurus, by Annas] |
| Full Idea: Epicurus alone among the ancient schools denies that in nature we find any teleological explanations. Nothing in nature is for anything, neither the world as a whole nor anything in it. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Julia Annas - Ancient Philosophy: very short introduction | |
| A reaction: This may explain the controversial position that epicureanism held in the seventeenth century, as well as its incipient atheism. |
| 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. |
| 20907 | Democritus says atoms have size and shape, and Epicurus added weight [Epicurus, by Ps-Plutarch] |
| Full Idea: Democritus said that the properties of the atoms are in number two, magnitude and shape, but Epicurus added to these a third one, weight. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by Pseudo-Plutarch - On the Doctrine of the Philosophers 1.3.18 | |
| A reaction: The addition of Epicurus seems very sensible, and an odd omission by Democritus. He seems to think that atoms have a uniform density, so that volume indicates weight. |
| 21669 | Atoms don't swerve by being struck, because they move in parallel, so the swerve is uncaused [Cicero on Epicurus] |
| Full Idea: The swerve of Epicurus takes place without a cause; it does not take place in consequence of being struck by another atom, since how can that take place if they are indivisible bodies travelling perpendicularly in straight lines by the force of gravity? | |
| From: comment on Epicurus (fragments/reports [c.289 BCE]) by M. Tullius Cicero - On Fate ('De fato') 10.22 | |
| A reaction: The swerve is the most ad hoc proposal in the history of theoretical physics. This is interesting for spelling out that the travel in vertical parallels. What's that all about, then? |
| 21680 | What causes atomic swerves? Do they draw lots? What decides the size or number of swerves? [Cicero on Epicurus] |
| Full Idea: What fresh cause exists in nature to make the atom swerve (or do the atoms cast lots among them which is to swerve and which not?), or to serve as the reason for making a very small swerve and not a large one, or one swerve, and not two or three swerves? | |
| From: comment on Epicurus (fragments/reports [c.289 BCE]) by M. Tullius Cicero - On Fate ('De fato') 20.46 | |
| A reaction: This is an appeal to the Principle of Sufficient Reason, which seems to be the main ground for rejecting the swerve. The only reason to accept the swerve is reluctance to accept determinism or fatalism. |
| 18257 | Why should the limit of measurement be points, not intervals? [Dummett] |
| Full Idea: By what right do we assume that the limit of measurement is a point, and not an interval? | |
| From: Michael Dummett (Frege philosophy of mathematics [1991], 22 'Quantit') |
| 14525 | Stoics say time is incorporeal and self-sufficient; Epicurus says it is a property of properties of things [Epicurus] |
| Full Idea: Stoics posited that time is an incorporeal which is conceived of all by itself, while Epicurus thinks that it is an accident of certain things, ...and he called in a property of properties. | |
| From: Epicurus (fragments/reports [c.289 BCE]) | |
| A reaction: [Source Sextus 'Adversus Mathematicos' 10.219-227] |
| 2637 | For Epicureans gods are made of atoms, and are not eternal [Epicurus, by Cicero] |
| Full Idea: For Epicureans the gods are made of atoms, so in that case they are not eternal. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by M. Tullius Cicero - On the Nature of the Gods ('De natura deorum') I.68 |
| 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) |
| 2633 | Epicurus saw that gods must exist, because nature has imprinted them on human minds [Epicurus, by Cicero] |
| Full Idea: Epicurus alone saw that gods must exist because nature herself has imprinted an idea of them in the minds of all mankind. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by M. Tullius Cicero - On the Nature of the Gods ('De natura deorum') I.43 |
| 2639 | Some say Epicurus only pretended to believe in the gods, so as not to offend Athenians [Epicurus, by Cicero] |
| Full Idea: Some believe that Epicurus gave lip-service only to the gods, so as not to offend the Athenians, but in fact did not believe in them. | |
| From: report of Epicurus (fragments/reports [c.289 BCE]) by M. Tullius Cicero - On the Nature of the Gods ('De natura deorum') I.84 |
| 14527 | If god answered prayers we would be destroyed, because we pray for others to suffer [Epicurus] |
| Full Idea: If god acted in accordance with the prayers of men, all men would rather quickly be destroyed, since they constantly pray for many sufferings to befall each other. | |
| From: Epicurus (fragments/reports [c.289 BCE]) | |
| A reaction: [source Maximus the Abbott 'Gnom.' 14] |