“From experience. That something is irrational is no argument against its existence, but rather a condition for it.”
Section IX, "Man Alone with Himself" / aphorism 515
Human, All Too Human (1878), Helen Zimmern translation
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Friedrich Nietzsche655
German philosopher, poet, composer, cultural critic, and cl… 1844–1900Related quotes
“In principio it is impossible to prove from experiments that something is non-existent.”
Felix Ehrenhaft (1879–1952) Austrian physicist
The Magnetic Current http://adsabs.harvard.edu/abs/1941Sci....94..232E, Science, Volume 94, Issue 2436, pp. 232-233 (September, 1941)
Emmanuel Levinas (1906–1995) French philosopher
The Theory Of Intuition In Husserls Phenomenology 1963, 1995 p. 9
George Holmes Howison (1834–1916) American philosopher
Source: The Limits of Evolution, and Other Essays, Illustrating the Metaphysical Theory of Personal Ideaalism (1905), Human Immortality: its Positive Argument, p.312
Robert G. Ingersoll (1833–1899) Union United States Army officer
Rome, or Reason? A Reply to Cardinal Manning. Part I. The North American Review (1888)
Greg Egan (1961) Australian science fiction writer and former computer programmer
Comment on Scott Aaronson's "Does it come with a 14-Gyr warranty?" http://www.scottaaronson.com/blog/?p=265#comment-7403 <br class="br">Other
“That maxim, it’s not an argument against atheism—it’s an argument against foxholes.”
James K. Morrow book Towing Jehovah
Source: Towing Jehovah (1994), Chapter 8, “Famine” (p. 213)
“The Pythagoreans discovered the existence of incommensurable lines, or of irrationals.”
Thomas Little Heath (1861–1940) British civil servant and academic
This was, doubtless, first discovered with reference to the diagonal of a square which is incommensurable with the side, being in the ratio to it of √2 to 1. The Pythagorean proof of this particular case survives in Aristotle and in a proposition interpolated in Euclid's Book X.; it is by a reductio ad absurdum proving that, if the diagonal is commensurable with the side, the same number must be both odd and even. This discovery of the incommensurable... showed that the theory of proportion invented by Pythagoras was not of universal application and therefore that propositions proved by means of it were not really established. ...The fatal flaw thus revealed in the body of geometry was not removed till Eudoxus discovered the great theory of proportion (expounded in Euclid's Book V.), which is applicable to incommensurable as well as to commensurable magnitudes.
Achimedes (1920)