| 21264 | Mortals are incapable of being fully rational [Plato] |
| Full Idea: We mustn't assume that mortal eyes will ever be able to look upon reason and get to know it adequately. | |
| From: Plato (The Laws [c.348 BCE], 897d) | |
| A reaction: This is in the context of the rational control of the whole Cosmos. I presume Plato would be flabbergasted by the findings of recent physics and cosmology. Did Kant believe that he was being completely rational about ethics? |
| 19740 | A very hungry man cannot choose between equidistant piles of food [Aristotle] |
| Full Idea: The man who, though exceedingly hungry and thirsty, and both equally, yet being equidistant from food and drink, is therefore bound to stay where he is. | |
| From: Aristotle (On the Heavens [c.336 BCE], 296b33) | |
| A reaction: This is, of course, Buridan's famous Ass, but this quotation has the advantage of precedence, and also of being expressed in an original quotation (which does not exist for Buridan). |
| 1800 | Sceptics say reason is only an instrument, because reason can only be attacked with reason [Pyrrho, by Diog. Laertius] |
| Full Idea: The Sceptics say that they only employ reason as an instrument, because it is impossible to overturn the authority of reason, without employing reason. | |
| From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.8 |
| 1815 | Reasoning needs arbitrary faith in preliminary hypotheses (Mode 14) [Agrippa, by Diog. Laertius] |
| Full Idea: Fourteenth mode: reasoning requires arbitrary faith in preliminary hypotheses. | |
| From: report of Agrippa (fragments/reports [c.60]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.10 |
| 1812 | All discussion is full of uncertainty and contradiction (Mode 11) [Agrippa, by Diog. Laertius] |
| Full Idea: Eleventh mode: all topics of discussion are full of uncertainty and contradiction. | |
| From: report of Agrippa (fragments/reports [c.60]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.10 |
| 1811 | Proofs often presuppose the thing to be proved (Mode 15) [Agrippa, by Diog. Laertius] |
| Full Idea: Fifteenth mode: proofs often presuppose the thing to be proved. | |
| From: report of Agrippa (fragments/reports [c.60]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.10 |
| 1813 | All reasoning endlessly leads to further reasoning (Mode 12) [Agrippa, by Diog. Laertius] |
| Full Idea: Twelfth mode: all reasoning leads on to further reasoning, and this process goes on forever. | |
| From: report of Agrippa (fragments/reports [c.60]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.10 |
| 23343 | Because reason performs all analysis, we should analyse reason - but how? [Epictetus] |
| Full Idea: Since it is reason that analyses and completes all other things, reason itself should not be left unanalysed. But by what shall it be analysed? ..That is why philosophers put logic first, just as when measuring grain we first examine the measure. | |
| From: Epictetus (The Discourses [c.56], 1.17.01) | |
| A reaction: The problem of the definitive metre rule in Paris. I say we have to test reason against the physical world, and the measure of reason is truth. Something has to be primitive, but reason is too vague for that role. Idea 23344 agrees with me! |
| 22752 | Reasoning is impossible without a preconception [Sext.Empiricus] |
| Full Idea: It is not possible either to seek or to doubt without a preconception. | |
| From: Sextus Empiricus (Against the Ethicists (one book) [c.180], II.22) | |
| A reaction: [Sextus quotes this from 'the sapient Epicurus'] I think this may be a message across the centuries to Hegel, who attempted this impossible feat. My picture of philosophy is a continual shift of the preconceptions, to explore thoroughly. |
| 1403 | A rational donkey would starve to death between two totally identical piles of hay [Buridan, by PG] |
| Full Idea: A rational donkey faced with two totally identical piles of hay would be unable to decide which one to eat first, and would therefore starve to death | |
| From: report of Jean Buridan (talk [1338]) by PG - Db (ideas) | |
| A reaction: also De Caelo 295b32 (Idea 19740). |
| 6675 | The heart has its reasons of which reason knows nothing [Pascal] |
| Full Idea: The heart has its reasons of which reason knows nothing. | |
| From: Blaise Pascal (Pensées [1662], 423 (277)) | |
| A reaction: This romantic remark has passed into folklore. I am essentially against it, but the role of intuition and instinct are undeniable in both reasoning and ethics. I don't feel inclined, though, to let my heart overrule my reason concerning what exists. |
| 19433 | The universe is infinitely varied, so the Buridan's Ass dilemma could never happen [Leibniz] |
| Full Idea: The Buridan's Ass case of perfect equilibrium is chimerical. ...The universe has no centre and its parts are infinitely varied; thus it will never happen that all will be perfectly equal and will strike equally from one side or the other. | |
| From: Gottfried Leibniz (Letters to Coste [1707], 1707) | |
| A reaction: Can the great Leibniz have missed the point? Surely all that matters is that the ass cannot distinguish the two options - not that they actually are identical in every detail? If the ass is short-sighted, that should be easy to set up. |
| 22520 | You can't reason someone out of an irrational opinion [Swift] |
| Full Idea: Reasoning will never make a man correct an ill opinion, which by reasoning he never acquired. | |
| From: Jonathan Swift (Letters to a Young Clergyman [1720]) | |
| A reaction: It would be hard to prove this, and someone full of irrational beliefs may have their rationality awakened by a sound argument. Nice remark, but too pessimistic. |
| 19767 | Reason leads to prudent selfishness, which overrules natural compassion [Rousseau] |
| Full Idea: Reason is what engenders egocentrism ...turns man in upon himself ...and separates him from all that troubles him and afflicts him. Philosophy is what ...moves him to say at the sight of a suffering man 'Perish if you will; I am safe and sound'. | |
| From: Jean-Jacques Rousseau (Discourse on the Origin of Inequality [1754], Part I) | |
| A reaction: He goes on to observe that fights in the marketplace are stopped by women, while the philosophers have all run away! This thinking leads to the sentimental movement, and then to romanticism. |
| 8099 | The truths of reason instruct, but they do not illuminate [Joubert] |
| Full Idea: There are truths that instruct, perhaps, but they do not illuminate. In this class are all the truths of reasoning. | |
| From: Joseph Joubert (Notebooks [1800], 1800) | |
| A reaction: A rather romantic view, which strikes me as false. An inspiring truth can suddenly collapse when you see why it must be false. Equally a line of reasoning can lead to a truth which need becomes an illumination. |
| 8932 | Truth does not come from giving reasons for and against propositions [Hegel] |
| Full Idea: The way of asserting a proposition, adducing reasons for it, and in the same way refuting its opposite by reasons, is not the form in which truth can appear. | |
| From: Georg W.F.Hegel (Phenomenology of Spirit [1807], Pref 48) | |
| A reaction: I can't see Plato or Aristotle agreeing with this. It is obviously the prelude to Hegel's dialectical account of reasoning. However, if we don't believe things because we have good reason to, I'm not sure where we shoud start. |
| 6558 | A foolish consistency is the hobgoblin of little minds [Emerson] |
| Full Idea: A foolish consistency is the hobgoblin of little minds, adored by little statesmen and philosophers and divines. With consistency a great soul has simply nothing to do. | |
| From: Ralph Waldo Emerson (Self-Reliance [1841], p.37) | |
| A reaction: A remark to warm the hearts of pragmatists, Wittgensteinians, Nietzscheans and the post-modern mob. But pay careful attention to the word "foolish". Robert Fogelin gives a very balanced view of the matter (e.g. Idea 6557). |
| 4523 | What can be 'demonstrated' is of little worth [Nietzsche] |
| Full Idea: What can be 'demonstrated' is of little worth. | |
| From: Friedrich Nietzsche (The Will to Power (notebooks) [1888], §431) | |
| A reaction: He admits that some things can be demonstrated, and that they have some worth. But demonstration may be a matter of coherence, so that anything can be demonstrated, by assuming a range of ideas as being beyond demonstration. |
| 8594 | People have had good reasons for thinking that the circle has been squared [Shoemaker] |
| Full Idea: People have had good reasons for thinking that the circle has been squared. | |
| From: Sydney Shoemaker (Time Without Change [1969], p.54) | |
| A reaction: A lovely concise illustration of the limits of reason. We might distinguish 'rational to us' from 'rational in itself', with only what is true or real aspiring to the latter status. But the latter might be unknowable by us. |
| 3092 | If you believe that some of your beliefs are false, then at least one of your beliefs IS false [Harman] |
| Full Idea: If a rational man believes he has at least some other false beliefs, it follows that a rational man knows that at least one of his beliefs is false (the one believed false, or this new belief). | |
| From: Gilbert Harman (Thought [1973], 7.2) |
| 7986 | Drunken boat pilots are less likely to collide than clearly focused ones [Baudrillard] |
| Full Idea: Two boats on Lake Constance in dense fog are in less danger of colliding if their pilots are drunk than if they are attempting to master the situation. | |
| From: Jean Baudrillard (The Intelligence of Evil [2004], p.196) | |
| A reaction: Charming, but I think empirical research would prove it false. At least rational pilots know to keep to the right (?) when a shape looms through the fog. I prefer rational pilots, but then I am one of those sad people who admires the Enlightenment. |
| 8062 | Proof is a barren idea in philosophy, and the best philosophy never involves proof [MacIntyre] |
| Full Idea: Arguments in philosophy rarely take the form of proofs; and the most successful arguments on topics central to philosophy never do. (The ideal of proof is a relatively barren one in philosophy). | |
| From: Alasdair MacIntyre (After Virtue: a Study in Moral Theory [1981], Ch.18) | |
| A reaction: He seems proud of this, but he must settle for something which is less than proof, which has to be vindicated to the mathematicians and scientists. I agree, though. Plato is the model, and the best philosophy builds a broad persuasive picture. |
| 3801 | Rationality requires the assumption that things are either for better or worse [Dennett] |
| Full Idea: We must assume that something matters - that some things are for better and some things are for worse, for without that our assumed rationality would have nothing on which to get a purchase. | |
| From: Daniel C. Dennett (Elbow Room: varieties of free will [1984], §7.1) | |
| A reaction: It does seem that rationality wouldn't exist as an activity without some value to motivate it. |
| 1591 | Unfortunately for reason, argument can't be used to establish the value of argument [Roochnik] |
| Full Idea: Unfortunately for the logos there is no argument that can, without begging the question, establish the goodness of argumentation. | |
| From: David Roochnik (The Tragedy of Reason [1990], p.106) |
| 1599 | Attempts to suspend all presuppositions are hopeless, because a common ground must be agreed for the process [Roochnik] |
| Full Idea: To debate about suspending all our presuppositions requires a common ground which, upon being established, immediately renders the debate superfluous. | |
| From: David Roochnik (The Tragedy of Reason [1990], p.144) |
| 18781 | Inconsistency doesn't prevent us reasoning about some system [Mares] |
| Full Idea: We are able to reason about inconsistent beliefs, stories, and theories in useful and important ways | |
| From: Edwin D. Mares (Negation [2014], 1) |
| 6557 | Humans may never be able to attain a world view which is both rich and consistent [Fogelin] |
| Full Idea: It might be wholly unreasonable to suppose that human beings will ever be able to attain a view of the world that is both suitably rich and completely consistent. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Intro) | |
| A reaction: Fogelin's lectures develop this view very persuasively. I think all philosophers must believe that the gods could attain a 'rich and consistent' view. Our problem is that we are a badly organised team, whose members keep dying. |
| 6568 | A game can be played, despite having inconsistent rules [Fogelin] |
| Full Idea: The presence of an inconsistency in the rules that govern a game need not destroy the game. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.2) | |
| A reaction: He only defends this thesis if the inconsistency is away from the main centre of the action. You can't have an inconsistent definition of scoring a goal or a touchdown. |