50 ideas
| 326 | For relaxation one can consider the world of change, instead of eternal things [Plato] |
| Full Idea: If, for relaxation, one gives up discussing eternal things, it is pleasant to consider likely accounts of the world of change. | |
| From: Plato (Timaeus [c.349 BCE], 59c) | |
| A reaction: To understand this, examine Plato's example of the Line at 'Republic' 509d. |
| 315 | Philosophy is the supreme gift of the gods to mortals [Plato] |
| Full Idea: Philosophy is the greatest gift the gods have ever given or ever will give to mortals. | |
| From: Plato (Timaeus [c.349 BCE], 47b) | |
| A reaction: I wonder why they gave it to us? |
| 3656 | The greatest good for a state is true philosophers [Descartes] |
| Full Idea: The greatest good which can exist in a state is to have true philosophers. | |
| From: René Descartes (Principles of Philosophy [1646], Pref) | |
| A reaction: …because they understand true reality, especially the Good. |
| 306 | Nothing can come to be without a cause [Plato] |
| Full Idea: Nothing can come to be without a cause. | |
| From: Plato (Timaeus [c.349 BCE], 28a) |
| 324 | Before the existence of the world there must have been being, space and becoming [Plato] |
| Full Idea: There were, before the world came into existence, being, space, and becoming, three distinct realities. | |
| From: Plato (Timaeus [c.349 BCE], 52d) |
| 20364 | The apprehensions of reason remain unchanging, but reasonless sensation shows mere becoming [Plato] |
| Full Idea: That which is apprehended by intelligence and reason is always in the same state, but that which is conceived by opinion with the help of sensation and without reason is always in a process of becoming and perishing, and never really is. | |
| From: Plato (Timaeus [c.349 BCE], 28a) | |
| A reaction: Lots of problems with this, of which I take the main one to be the idea that sensation is 'without reason', as if there were a sharp dichotomy in our ways of evaluating reality. Laws of nature seem to be laws of change, not of stasis. |
| 16705 | Whiteness isn't created in an alteration, because it is just this-being-white [Oresme] |
| Full Idea: If it is said that whiteness begins to be through alteration, this does not hold, because whiteness is nothing other than this-being-white. | |
| From: Nicole Oresme (On 'Generation and Corruption' [1349], I.2), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 19.3 | |
| A reaction: This innocent-looking remark is dynamite, because it rejects the separability of qualities, which threatens the doctrine of Transubstantiation. |
| 16744 | All powers can be explained by obvious features like size, shape and motion of matter [Descartes] |
| Full Idea: There are no powers in stones and plants that are not so mysterious that they cannot be explained …from principles that are known to all and admitted by all, namely the shape, size, position, and motion of particles of matter. | |
| From: René Descartes (Principles of Philosophy [1646], IV.187), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 23.6 | |
| A reaction: This is an invocation of 'categorical' properties, against dispositions. I take this to be quite wrong. The explanation goes the other way. What supports the structures; what drives the motion; what initiates anything? |
| 5016 | Five universals: genus, species, difference, property, accident [Descartes] |
| Full Idea: The five commonly enumerated universals are: genus, species, difference, property and accident. | |
| From: René Descartes (Principles of Philosophy [1646], I.59) | |
| A reaction: Interestingly, this seems to be Descartes passing on his medieval Aristotelian inheritance, in which things are defined by placing them in a class, and then noting what distinguishes them within that class. |
| 12042 | Plato's Forms were seen as part of physics, rather than of metaphysics [Plato, by Annas] |
| Full Idea: In the ancient world Plato's Theory of Forms was mostly seen as one aspect of Plato's 'physics' or theory of the world (rather than as 'metaphysics'). | |
| From: report of Plato (Timaeus [c.349 BCE]) by Julia Annas - Ancient Philosophy: very short introduction Ch.5 | |
| A reaction: This is how I also see the theory, but then I am inclined to see religion as a rather startling branch of speculative physics. Annas cites 'Timaeus' as the key text for this. |
| 307 | Something will always be well-made if the maker keeps in mind the eternal underlying pattern [Plato] |
| Full Idea: Whenever the maker of anything keeps his eye on the eternally unchanging and uses it as his pattern for the form and function of his product the result must be good. | |
| From: Plato (Timaeus [c.349 BCE], 28b) |
| 318 | In addition to the underlying unchanging model and a changing copy of it, there must also be a foundation of all change [Plato] |
| Full Idea: In addition to an eternal unchanging model and a visible and changing copy of reality, there must be a third part, the receptacle and nurse of all becoming and change. | |
| From: Plato (Timaeus [c.349 BCE], 49b) | |
| A reaction: cf Aristotle's criticism in Metaphysics |
| 321 | For knowledge and true opinion to be different there must be Forms; otherwise we are just stuck with sensations [Plato] |
| Full Idea: If intelligence and true opinion are different, then the forms must exist, but if they are the same, then what our senses perceive must be the most certain reality. | |
| From: Plato (Timaeus [c.349 BCE], 51d) |
| 317 | The universe is basically an intelligible and unchanging model, and a visible and changing copy of it [Plato] |
| Full Idea: Our basic description of the universe contained an intelligible and unchanging model, and a visible and changing copy of it. | |
| From: Plato (Timaeus [c.349 BCE], 48e) |
| 5015 | A universal is a single idea applied to individual things that are similar to one another [Descartes] |
| Full Idea: Universals arise solely from the fact that we avail ourselves of one idea in order to think of all individual things that have a certain similitude. When we understand under the same name all the objects represented by this idea, that name is universal. | |
| From: René Descartes (Principles of Philosophy [1646], I.59) | |
| A reaction: Judging by the boldness of the pronouncement, it looks as if Descartes hasn't recognised the complexity of the problem. How do we spot a 'similarity', especially an abstraction like 'tool' or 'useful'? This sounds like Descartes trying to avoid Platonism. |
| 16630 | If we perceive an attribute, we infer the existence of some substance [Descartes] |
| Full Idea: Based on perceiving the presence of some attribute, we conclude there must also be present an existing thing or substance to which it can be attributed. | |
| From: René Descartes (Principles of Philosophy [1646], I.52), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 08.1 | |
| A reaction: A rainbow might be a tricky case. This illustrates the persistent belief in substances, even among philosophers who embraced the new corpuscular and mechanistic view of matter. |
| 5013 | A substance needs nothing else in order to exist [Descartes] |
| Full Idea: By substance we can understand nothing else than a thing which so exists that it needs no other thing in order to exist. | |
| From: René Descartes (Principles of Philosophy [1646], I.51) | |
| A reaction: Properties, of course, are the things which have dependent existence. Can properties be reduced to substances (e.g. by adopting a materialist theory of mind)? Note that Descartes does not think that substances depend on God for existence. |
| 16633 | A substance has one principal property which is its nature and essence [Descartes] |
| Full Idea: Each substance has one principal property that constitutes its nature and essence, to which all its other properties are referred. Extension in length, breadth, and depth constitutes the nature of corporeal substance; and thought of thinking substances. | |
| From: René Descartes (Principles of Philosophy [1646], I.53), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 08.3 | |
| A reaction: Property is likely to be 'propria', which is a property distinctive of some thing, not just any old modern property. This is quite a strikingly original view of the nature of essence. Descartes despised 'substantial forms'. |
| 3658 | Total doubt can't include your existence while doubting [Descartes] |
| Full Idea: He who decides to doubt everything cannot nevertheless doubt that he exists while he doubts. | |
| From: René Descartes (Principles of Philosophy [1646], Pref) |
| 5005 | I think, therefore I am, because for a thinking thing to not exist is a contradiction [Descartes] |
| Full Idea: There is a contradiction in conceiving that what thinks does not (at the same time as it thinks) exist. Hence this conclusion I think, therefore I am, is the first and most certain that occurs to one who philosophises in an orderly way. | |
| From: René Descartes (Principles of Philosophy [1646], I.07) | |
| A reaction: The classic statement of his argument. The significance here is that it seems to have the structure of an argument, as it involves 'philosophising', which leads to a 'contradiction', and hence to the famous conclusion. It is not just intuitive. |
| 5006 | 'Thought' is all our conscious awareness, including feeling as well as understanding [Descartes] |
| Full Idea: By the word 'thought' I understand everything we are conscious of as operating in us. And that is why not only understanding, willing, imagining, but also feeling, are here the same thing as thinking. | |
| From: René Descartes (Principles of Philosophy [1646], I.09) | |
| A reaction: There is a bit of tension here between Descartes' correct need to include feeling in thought for his Cogito argument, and his tendency to dismiss animal consciousness, on the grounds that they only sense things, and don't make judgements. |
| 5012 | 'Nothing comes from nothing' is an eternal truth found within the mind [Descartes] |
| Full Idea: The proposition 'nothing comes from nothing' is not to be considered as an existing thing, or the mode of a thing, but as a certain eternal truth which has its seat in our mind and is a common notion or axiom. | |
| From: René Descartes (Principles of Philosophy [1646], I.49) | |
| A reaction: There is a tension here, in his assertion that it is 'eternal', but 'not existing'. How does one distinguish an innate idea from an innate truth? 'Eternal' sounds like an external guarantee of truth, but being 'in our mind' sounds less reliable. |
| 334 | Only bird-brained people think astronomy is entirely a matter of evidence [Plato] |
| Full Idea: Birds are empty-headed men who grew feathers instead of hair, because they were interested in astronomy but thought it was entirely a matter of physical evidence. | |
| From: Plato (Timaeus [c.349 BCE], 91d) |
| 5004 | We can know basic Principles without further knowledge, but not the other way round [Descartes] |
| Full Idea: It is on the Principles, or first causes, that the knowledge of other things depends, so the Principles can be known without these last, but the other things cannot reciprocally be known without the Principles. | |
| From: René Descartes (Principles of Philosophy [1646], Pref) | |
| A reaction: A particularly strong assertion of foundationalism, as it says that not only must the foundations exist, but also we must actually know them. This sounds false, as elementary knowledge then seems to require far too much sophistication. |
| 5962 | Plato says the soul is ordered by number [Plato, by Plutarch] |
| Full Idea: Plato regards the substance of soul not as number but as being ordered by number. | |
| From: report of Plato (Timaeus [c.349 BCE]) by Plutarch - 68: Generation of the soul in 'Timaeus' 1023 | |
| A reaction: This remark points towards Plato's esoteric doctrines, which are some sort of mathematical metaphysics. The idea that order and numbers are in some way connected is one of the most powerful in western civilization, with undeniable appeal. |
| 5014 | We can understand thinking occuring without imagination or sensation [Descartes] |
| Full Idea: We can understand thinking without imagination or sensation, as is quite clear to anyone who attends to the matter. | |
| From: René Descartes (Principles of Philosophy [1646], I.53) | |
| A reaction: We may certainly take it that Descartes means if it is understandable then it is logically possible. To believe that thinking could occur without imagination strikes me as an astonishing error. I take imagination to be more central than understanding. |
| 5017 | In thinking we shut ourselves off from other substances, showing our identity and separateness [Descartes] |
| Full Idea: Because each one of us understands what he thinks, and that in thinking he can shut himself off from every other substance, we may conclude that each of us is really distinct from every other thinking substance and from corporeal substance. | |
| From: René Descartes (Principles of Philosophy [1646], I.60) | |
| A reaction: This seems to be a novel argument which requires elucidation. I can 'shut myself off from every other substance'? If I shut myself off from thinking about food, does that mean hunger is not part of me? Or convince yourself that you don't have a brother? |
| 5010 | Our free will is so self-evident to us that it must be a basic innate idea [Descartes] |
| Full Idea: It is so evident that we are possessed of a free will that can give or withhold its assent, that this may be counted as one of the first and most common notions found innately in us. | |
| From: René Descartes (Principles of Philosophy [1646], I.39) | |
| A reaction: It seems to me plausible to say that we have an innate conception of our own will (our ability to make decisions), though Hume says we only learn about the will from experience, but the idea that it is absolutely 'free' might never cross our minds. |
| 330 | No one wants to be bad, but bad men result from physical and educational failures, which they do not want or choose [Plato] |
| Full Idea: No one wishes to be bad, but a bad man is bad because of some flaw in his physical makeup and failure in his education, neither of which he likes or chooses. | |
| From: Plato (Timaeus [c.349 BCE], 86e) |
| 5011 | There are two ultimate classes of existence: thinking substance and extended substance [Descartes] |
| Full Idea: I observe two ultimate classes of things: intellectual or thinking things, pertaining to the mind or to thinking substance, and material things, pertaining to extended substance or to body. | |
| From: René Descartes (Principles of Philosophy [1646], I.48) | |
| A reaction: This is clear confirmation that Descartes believed the mind is a substance, rather than an insubstantial world of thinking. It leaves open the possibility of a different theory: that mind is not a substance, but is a Platonic adjunct to reality. |
| 5018 | Even if tightly united, mind and body are different, as God could separate them [Descartes] |
| Full Idea: Even if we suppose God had united a body and a soul so closely that they couldn't be closer, and made a single thing out of the two, they would still remain distinct, because God has the power of separating them, or conserving out without the other. | |
| From: René Descartes (Principles of Philosophy [1646], I.60) | |
| A reaction: If Descartes lost his belief in God (after discussing existence with Kant) would he cease to be a dualist? This quotation seems to be close to conceding a mind-body relationship more like supervenience than interaction. |
| 5007 | Most errors of judgement result from an inaccurate perception of the facts [Descartes] |
| Full Idea: What usually misleads us is that we very frequently form a judgement although we do not have an accurate perception of what we judge. | |
| From: René Descartes (Principles of Philosophy [1646], I.33) | |
| A reaction: This seems to me a generally accurate observation, particularly in the making of moral judgements (which was probably not what Descartes was considering). The implication is that judgements are to a large extent forced by our perceptions. |
| 5009 | We do not praise the acts of an efficient automaton, as their acts are necessary [Descartes] |
| Full Idea: We do not praise automata, although they respond exactly to the movements they were designed to produce, since their actions are performed necessarily | |
| From: René Descartes (Principles of Philosophy [1646], I.37) | |
| A reaction: I say we attribute responsibility when we perceive something like a 'person' as causing them. We don't blame small animals, because there is 'no one at home', but we blame children as they develop a full character and identity. We can ignore free will. |
| 5008 | The greatest perfection of man is to act by free will, and thus merit praise or blame [Descartes] |
| Full Idea: That the will should extend widely accords with its nature, and it is the greatest perfection in man to be able to act by its means, that is, freely, and by so doing we are in peculiar way masters of our actions, and thereby merit praise or blame. | |
| From: René Descartes (Principles of Philosophy [1646], I.37) | |
| A reaction: This seems to me to be a deep-rooted and false understanding which philosophy has inherited from theology. It doesn't strike me that there must an absolute 'buck-stop' to make us responsible. Why is it better for a decision to appear out of nowhere? |
| 316 | Music has harmony like the soul, and serves to reorder disharmony within us [Plato] |
| Full Idea: Music has harmonic motions like the orbits of the soul, and is not for irrational pleasure, but to reduce to order any disharmony in the revolutions within us. | |
| From: Plato (Timaeus [c.349 BCE], 47d) |
| 332 | One should exercise both the mind and the body, to avoid imbalance [Plato] |
| Full Idea: One should preserve a balance and avoid exercising the mind or body without the other; mathematicians should exercise physically, and athletes mentally. | |
| From: Plato (Timaeus [c.349 BCE], 88c) | |
| A reaction: Excellent, and very modern. Use it or lose it. It suggests that Plato had a fairly holistic view of a human being, and saw mind and body as closely integrated. |
| 328 | Everything that takes place naturally is pleasant [Plato] |
| Full Idea: Everything that takes place naturally is pleasant. | |
| From: Plato (Timaeus [c.349 BCE], 81e) | |
| A reaction: Not many people would agree with this. I recently watched a sparrowhawk eat a pigeon in my garden. This is the source of the stoic formula of living according to nature. |
| 322 | Intelligence is the result of rational teaching; true opinion can result from irrational persuasion [Plato] |
| Full Idea: Intelligence is produced by teaching, involves truth and reason, and cannot be moved; true opinion involves persuasion, is irrational and can be moved. | |
| From: Plato (Timaeus [c.349 BCE], 51e) |
| 331 | Bad governments prevent discussion, and discourage the study of virtue [Plato] |
| Full Idea: Under a bad government discussion, both public and private, is bad, and no courses of study are available to cure faults of character. | |
| From: Plato (Timaeus [c.349 BCE], 87b) |
| 311 | The cosmos must be unique, because it resembles the creator, who is unique [Plato] |
| Full Idea: So that our universe can resemble the perfect living creature in being unique, the universe was, is and will continue to be its maker's only creation. | |
| From: Plato (Timaeus [c.349 BCE], 31c) |
| 15987 | Physics only needs geometry or abstract mathematics, which can explain and demonstrate everything [Descartes] |
| Full Idea: I do not accept or desire any other principle in physics than in geometry or abstract mathematics, because all the phenomena of nature may be explained by their means, and sure demonstrations can be given of them. | |
| From: René Descartes (Principles of Philosophy [1646], 2.64), quoted by Peter Alexander - Ideas, Qualities and Corpuscles 7 | |
| A reaction: This is his famous and rather extreme view, which might be described as hyper-pythagoreanism (by adding geometry to numbers). It seems to leave out matter, forces and activity. |
| 310 | The creator of the cosmos had no envy, and so wanted things to be as like himself as possible [Plato] |
| Full Idea: This changing cosmos was made because its maker is good, and therefore lacks envy; he therefore wished all things to be as like himself as possible. | |
| From: Plato (Timaeus [c.349 BCE], 29e) |
| 12730 | We will not try to understand natural or divine ends, or final causes [Descartes] |
|
Full Idea:
We will not seek for the reason of natural things from the end which God or nature has set before him in their creation |
|
| From: René Descartes (Principles of Philosophy [1646], §28) | |
| A reaction: Teleology is more relevant to biology than to the other sciences, and it is hard to understand an eye without a notion of 'what it is for'. Planetary motion reveals nothing about purposes. If you demand a purpose, it becomes more baffling. |
| 325 | We must consider the four basic shapes as too small to see, only becoming visible in large numbers [Plato] |
| Full Idea: We must think of the individual units of all four basic shapes as being far too small to be visible, and only becoming visible when massed together in large numbers. | |
| From: Plato (Timaeus [c.349 BCE], 56c) |
| 16601 | Matter is not hard, heavy or coloured, but merely extended in space [Descartes] |
| Full Idea: The nature of matter, or body viewed as a whole, consists not in its being something which is hard, heavy, or colored, or which in any other way affects the senses, but only in its being a thing extended in length, breadth and depth. | |
| From: René Descartes (Principles of Philosophy [1646], 2.4), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 04.5 |
| 327 | There are two types of cause, the necessary and the divine [Plato] |
| Full Idea: We must distinguish two types of cause, the necessary and the divine. | |
| From: Plato (Timaeus [c.349 BCE], 68e) |
| 314 | Heavenly movements gave us the idea of time, and caused us to inquire about the heavens [Plato] |
| Full Idea: Days, months, years and solstices have caused the invention of number, given us the notion of time, and caused us to inquire into the nature of the universe. | |
| From: Plato (Timaeus [c.349 BCE], 47a) |
| 312 | Time came into existence with the heavens, so that there will be a time when they can be dissolved [Plato] |
| Full Idea: Time came into being with the heavens, so that they should be dissolved together if ever they are dissolved. | |
| From: Plato (Timaeus [c.349 BCE], 38c) |
| 309 | Clearly the world is good, so its maker must have been concerned with the eternal, not with change [Plato] |
| Full Idea: If the world is beautiful and its maker good, he had an eye on the eternal; if not, on that which is subject to change; clearly the world is the fairest of things, and he the best of causes, so it is eternal. | |
| From: Plato (Timaeus [c.349 BCE], 29a) |
| 308 | If the cosmos is an object of perception then it must be continually changing [Plato] |
| Full Idea: The cosmos is visible, tangible and corporeal, and therefore perceptible by the senses; therefore it is an object of opinion and sensation, and therefore change and coming into being. | |
| From: Plato (Timaeus [c.349 BCE], 28d) |