29 ideas
3600 | Slow and accurate thought makes the greatest progress [Descartes] |
Full Idea: Those who go forward only very slowly can progress much further if they always keep to the right path, than those who run and wander off it. | |
From: René Descartes (A Discourse on Method [1637], §1.2) | |
A reaction: Like Descartes' 'Method'. This seems to place a low value on 'nous' or intuition. |
3601 | Most things in human life seem vain and useless [Descartes] |
Full Idea: Looking at the various activities and enterprises of mankind with the eye of a philosopher, there is hardly one which does not seem to me vain and useless. | |
From: René Descartes (A Discourse on Method [1637], §1.3) | |
A reaction: Well, yes. The obvious retort is that everything is vain and useless; or if not, then certainly metaphysics is. Useful for what? Is ornamental gardening useless, or sport? Art? What is the use of cosmology? He's right, of course. |
3602 | Almost every daft idea has been expressed by some philosopher [Descartes] |
Full Idea: There is nothing one can imagine so strange or so unbelievable that has not been said by one or other of the philosophers. | |
From: René Descartes (A Discourse on Method [1637], §2.16) | |
A reaction: Actually I think that extensive areas of logical possibilities for existence remain totally unexplored. On the other hand, most of the metaphysical beliefs of most of the human race, including the majority of philosophers, strike me as being false. |
3603 | Methodical thinking is cautious, analytical, systematic, and panoramic [Descartes, by PG] |
Full Idea: Descartes' four principles for his method of thinking are: be cautious, analyse the problem, be systematic from simple to complex, and keep an overview of the problem | |
From: report of René Descartes (A Discourse on Method [1637], §2.18) by PG - Db (ideas) |
3612 | Clear and distinct conceptions are true because a perfect God exists [Descartes] |
Full Idea: That the things we grasp very clearly and very distinctly are all true, is assured only because God is or exists, and because he is a perfect Being. | |
From: René Descartes (A Discourse on Method [1637], §4.38) |
3610 | Truth is clear and distinct conception - of which it is hard to be sure [Descartes] |
Full Idea: I take it as a general rule that the things we conceive very clearly and very distinctly are all true, but that there is merely some difficulty in properly discerning which are those which we distinctly conceive. | |
From: René Descartes (A Discourse on Method [1637], §4.33) |
17884 | Mathematical set theory has many plausible stopping points, such as finitism, and predicativism [Koellner] |
Full Idea: There are many coherent stopping points in the hierarchy of increasingly strong mathematical systems, starting with strict finitism, and moving up through predicativism to the higher reaches of set theory. | |
From: Peter Koellner (On the Question of Absolute Undecidability [2006], Intro) |
17893 | 'Reflection principles' say the whole truth about sets can't be captured [Koellner] |
Full Idea: Roughly speaking, 'reflection principles' assert that anything true in V [the set hierarchy] falls short of characterising V in that it is true within some earlier level. | |
From: Peter Koellner (On the Question of Absolute Undecidability [2006], 2.1) |
17894 | We have no argument to show a statement is absolutely undecidable [Koellner] |
Full Idea: There is at present no solid argument to the effect that a given statement is absolutely undecidable. | |
From: Peter Koellner (On the Question of Absolute Undecidability [2006], 5.3) |
17890 | There are at least eleven types of large cardinal, of increasing logical strength [Koellner] |
Full Idea: Some of the standard large cardinals (in order of increasing (logical) strength) are: inaccessible, Mahlo, weakly compact, indescribable, Erdös, measurable, strong, Wodin, supercompact, huge etc. (...and ineffable). | |
From: Peter Koellner (On the Question of Absolute Undecidability [2006], 1.4) | |
A reaction: [I don't understand how cardinals can have 'logical strength', but I pass it on anyway] |
17887 | PA is consistent as far as we can accept, and we expand axioms to overcome limitations [Koellner] |
Full Idea: To the extent that we are justified in accepting Peano Arithmetic we are justified in accepting its consistency, and so we know how to expand the axiom system so as to overcome the limitation [of Gödel's Second Theorem]. | |
From: Peter Koellner (On the Question of Absolute Undecidability [2006], 1.1) | |
A reaction: Each expansion brings a limitation, but then you can expand again. |
17891 | Arithmetical undecidability is always settled at the next stage up [Koellner] |
Full Idea: The arithmetical instances of undecidability that arise at one stage of the hierarchy are settled at the next. | |
From: Peter Koellner (On the Question of Absolute Undecidability [2006], 1.4) |
4577 | There is no necessity higher than natural necessity, and that is just regularity [Quine] |
Full Idea: In principle I see no higher or more austere necessity than natural necessity; and in natural necessity, or our attribution of it, I see only Hume's regularities | |
From: Willard Quine (Necessary Truth [1963], p.76) | |
A reaction: Presumably this allows logical necessity as a 'lower' necessity, but denies 'metaphysical' necessity, in line with Hume and other tough empiricists. Personally I adore metaphysical necessities, but they are a bit hard to establish conclusively. |
3605 | We can believe a thing without knowing we believe it [Descartes] |
Full Idea: The action of thought by which one believes a thing, being different from that by which one knows that one believes it, they often exist the one without the other. | |
From: René Descartes (A Discourse on Method [1637], §3.23) |
1583 | In morals Descartes accepts the conventional, but rejects it in epistemology [Roochnik on Descartes] |
Full Idea: Descartes' procedure for treating values (accepting normal conventions when faced with uncertainty) is the exact antithesis of that used to attain knowledge. | |
From: comment on René Descartes (A Discourse on Method [1637], §3.23) by David Roochnik - The Tragedy of Reason p.73 |
3607 | In thinking everything else false, my own existence remains totally certain [Descartes] |
Full Idea: While I decided to think that everything was false, it followed necessarily that I who thought thus must be something; the truth 'I think therefore I am' was so certain that the most extravagant scepticism could never shake it. | |
From: René Descartes (A Discourse on Method [1637], §4.32) |
3617 | I aim to find the principles and causes of everything, using the seeds within my mind [Descartes] |
Full Idea: I have tried to find in general the principles or first causes of everything which is or which may be in the world, ..without taking them from any other source than from certain seeds of truth which are naturally in our minds. | |
From: René Descartes (A Discourse on Method [1637], §6.64) |
3611 | Understanding, rather than imagination or senses, gives knowledge [Descartes] |
Full Idea: Neither our imagination nor our senses could ever assure us of anything, if our understanding did not intervene. | |
From: René Descartes (A Discourse on Method [1637], §4.37) |
3606 | I was searching for reliable rock under the shifting sand [Descartes] |
Full Idea: My whole plan had for its aim simply to give me assurance, and the rejection of shifting ground and sand in order to find rock or clay. | |
From: René Descartes (A Discourse on Method [1637], §3.29) | |
A reaction: I take this to be characteristic of an age when religion is being quietly rocked by the revival of ancient scepticism. If he'd settled for fallibilism, our civilization would have gone differently. |
3604 | When rebuilding a house, one needs alternative lodgings [Descartes] |
Full Idea: Before beginning to rebuild the house in which one lives…. one must also provide oneself with some other accommodation in which to be lodge conveniently while the work is going on. | |
From: René Descartes (A Discourse on Method [1637], §3.22) |
3618 | Only experiments can settle disagreements between rival explanations [Descartes] |
Full Idea: I observe almost no individual effect without immediately knowing that it can be deduced in many different ways, ..and I know of no way to resolve this but by experiments such that the results are different according to different explanations. | |
From: René Descartes (A Discourse on Method [1637], §6.65) |
3615 | Little reason is needed to speak, so animals have no reason at all [Descartes] |
Full Idea: Animals not only have less reason than men, but they have none at all; for we see that very little of it is required in order to be able to speak. | |
From: René Descartes (A Discourse on Method [1637], §5.58) |
3609 | I am a thinking substance, which doesn't need a place or material support [Descartes] |
Full Idea: I concluded that I was a substance, of which the whole essence or nature consists in thinking, and which, in order to exist, needs no place and depends on no material thing. | |
From: René Descartes (A Discourse on Method [1637], §4.33) | |
A reaction: To me that sounds like "I concluded that I wasn't a human being", which highlights the bizarre wishful thinking that seems to have gripped the human race for the first few thousand years of its serious thinking. |
3608 | I can deny my body and the world, but not my own existence [Descartes] |
Full Idea: I could pretend that I had no body, and that there was no world or place that I was in, but I could not, for all that, pretend that I did not exist. | |
From: René Descartes (A Discourse on Method [1637], §4.32) | |
A reaction: He makes the (in my opinion) appalling blunder of thinking that because he can pretend that he has no body, that therefore he might not have one. I can pretend that gold is an unusual form of cheese. However, "I don't exist" certainly sounds wrong. |
3613 | Reason is universal in its responses, but a physical machine is constrained by its organs [Descartes] |
Full Idea: Whereas reason is a universal instrument which can serve on any kind of occasion, the organs of a machine need a disposition for each action; so it is impossible to have enough different organs in a machine to respond to all the occurrences of life. | |
From: René Descartes (A Discourse on Method [1637], §5.57) | |
A reaction: How can Descartes know that reason is 'universal' rather than just 'very extensive'? Is there any information which cannot be encoded in a computer? It doesn't feel as if there any intrinsic restrictions to reason, but note Idea 4688. |
3616 | The soul must unite with the body to have appetites and sensations [Descartes] |
Full Idea: It is not sufficient that the reasonable soul should be lodged in the body like a pilot in a ship, unless perhaps to move its limbs, but it needs to be united more closely with the body in order to have sensations and appetites, and so be a true man. | |
From: René Descartes (A Discourse on Method [1637], §5.59) | |
A reaction: The idea that the pineal gland is the link suggests that Descartes has the 'pilot' view, but this idea shows that he believes in very close and complex interaction between mind and body. But how can a mind 'have' appetites if it has no physical needs? |
3614 | A machine could speak in response to physical stimulus, but not hold a conversation [Descartes] |
Full Idea: One may conceive of a machine made so as to emit words, and even emit them in response to a change in its bodily organs, such as being touched, but not to reply to the sense of everything said in its presence, as the most unintelligent men can. | |
From: René Descartes (A Discourse on Method [1637], §5.56) | |
A reaction: A critique of the Turing Test, written in 1637! You have to admire. Because of the advent of the microprocessor, we can 'conceive' more sophisticated, multi-level machines than Descartes could come up with. |
1581 | Greeks elevate virtues enormously, but never explain them [Descartes] |
Full Idea: The ancient pagans place virtues on a high plateau and make them appear the most valuable thing in the world, but they do not sufficiently instruct us about how to know them. | |
From: René Descartes (A Discourse on Method [1637], §1.8) |
16686 | God has established laws throughout nature, and implanted ideas of them within us [Descartes] |
Full Idea: I have noticed certain laws that God has so established in nature, and of which he has implanted such notions in our souls, that …we cannot doubt that they are exactly observed in everything that exists or occurs in the world. | |
From: René Descartes (A Discourse on Method [1637], pt 5), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 15.5 | |
A reaction: This is the view of laws which still seems to be with us (and needs extirpating) - that some outside agency imposes them on nature. I suspect that even Richard Feynman thought of laws like that, because he despised philosophy, and was thus naďve. |