| 21264 | Mortals are incapable of being fully rational [Plato] |
| 19740 | A very hungry man cannot choose between equidistant piles of food [Aristotle] |
| 1800 | Sceptics say reason is only an instrument, because reason can only be attacked with reason [Pyrrho, by Diog. Laertius] |
| 1815 | Reasoning needs arbitrary faith in preliminary hypotheses (Mode 14) [Agrippa, by Diog. Laertius] |
| 1813 | All reasoning endlessly leads to further reasoning (Mode 12) [Agrippa, by Diog. Laertius] |
| 1811 | Proofs often presuppose the thing to be proved (Mode 15) [Agrippa, by Diog. Laertius] |
| 1812 | All discussion is full of uncertainty and contradiction (Mode 11) [Agrippa, by Diog. Laertius] |
| 23343 | Because reason performs all analysis, we should analyse reason - but how? [Epictetus] |
| 22752 | Reasoning is impossible without a preconception [Sext.Empiricus] |
| 1403 | A rational donkey would starve to death between two totally identical piles of hay [Buridan, by PG] |
| 6675 | The heart has its reasons of which reason knows nothing [Pascal] |
| 19433 | The universe is infinitely varied, so the Buridan's Ass dilemma could never happen [Leibniz] |
| 22520 | You can't reason someone out of an irrational opinion [Swift] |
| 19767 | Reason leads to prudent selfishness, which overrules natural compassion [Rousseau] |
| 8099 | The truths of reason instruct, but they do not illuminate [Joubert] |
| 8932 | Truth does not come from giving reasons for and against propositions [Hegel] |
| 6558 | A foolish consistency is the hobgoblin of little minds [Emerson] |
| 4523 | What can be 'demonstrated' is of little worth [Nietzsche] |
| 8594 | People have had good reasons for thinking that the circle has been squared [Shoemaker] |
| 3092 | If you believe that some of your beliefs are false, then at least one of your beliefs IS false [Harman] |
| 7986 | Drunken boat pilots are less likely to collide than clearly focused ones [Baudrillard] |
| 8062 | Proof is a barren idea in philosophy, and the best philosophy never involves proof [MacIntyre] |
| 3801 | Rationality requires the assumption that things are either for better or worse [Dennett] |
| 1591 | Unfortunately for reason, argument can't be used to establish the value of argument [Roochnik] |
| 1599 | Attempts to suspend all presuppositions are hopeless, because a common ground must be agreed for the process [Roochnik] |
| 18781 | Inconsistency doesn't prevent us reasoning about some system [Mares] |
| 6557 | Humans may never be able to attain a world view which is both rich and consistent [Fogelin] |
| 6568 | A game can be played, despite having inconsistent rules [Fogelin] |