Appeal to ignorance - the claim that whatever has not been proved false must be true, and vice versa (e. g. There is no compelling evidence that UFOs are not visiting the Earth; therefore UFOs exist - and there is intelligent life elsewhere in the universe. Or: There may be seventy kazillion other worlds, but not one is known to have the moral advancement of the Earth, so we're still central to the Universe.) This impatience with ambiguity can be criticized in the phrase: absence of evidence is not evidence of absence. (Carl Sagan)

Appeal to ignorance - the claim that whatever has not been proved false must be true, and vice versa (e. g. There is no compelling evidence that UFOs are not visiting the Earth; therefore UFOs exist - and there is intelligent life elsewhere in the universe. Or: There may be seventy kazillion other worlds, but not one is known to have the moral advancement of the Earth, so we're still central to the Universe.) This impatience with ambiguity can be criticized in the phrase: absence of evidence is not evidence of absence.

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absence advancement ambiguity central claim compelling earth elsewhere false ignorance known vice whatever

Related quotes

Reports that say that something hasn't happened are always interesting to me, because as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns - the ones we don't know we don't know. And if one looks throughout the history of our country and other free countries, it is the latter category that tend to be the difficult ones. The absence of evidence is not evidence of absence, or vice versa.

Donald Rumsfeld

If, in pursuing this object, we employ our skill in research, not in forming vain conjectures; and if data are to be found, on which Science may form just conclusions, we should not long remain in ignorance with respect to the natural history of this Earth, a subject on which hitherto opinion only, and not evidence, has decided. For in no subject is there naturally less defect of evidence, although philosophers, led by prejudice, or misguided by false theory, have neglected to employ that light by which they should have seen the system of the world.

Stephen Baxter

This, obviously, is a fallacious argument. That same negative evidence can used to "prove" that molemen from beneath the surface of the earth have perpetrated these murders. The fact that the molemen have left no evidence behind proves how good they are at remaining hidden. That no sewer or road building projects have ever cut across their tunnels proves that politicians and engineers and other professionals are in league with the molemen. Just as obviously, anyone who denies the molemen exist is either in league with them, or is a fool who cannot see the end coming.

Michael A. Stackpole

Is there not therefore rational necessity, but vital anguish that impels us to believe in God. And to believe in God - I must reiterate it yet again - is, before all and above all, to feel a hunger for God, a hunger for divinity, to be sensible to his lack and absence, to wish that God may exist. And it is the wish to save the human finality of the Universe. For one might even come to resign oneself to being absorbed by God, if it be that our consciousness is based upon Consciousness, if consciousness is the end of the Universe.

Miguel de Unamuno

The principle of maximum diversity says that the laws of nature, and the initial conditions at the beginning of time, are such as to make the universe as interesting as possible. As a result, life is possible but not too easy. Maximum diversity often leads to maximum stress. In the end we survive, but only by the skin of our teeth. This is the confession of faith of a scientific heretic. Perhaps I may claim as evidence for progress in religion the fact that we no longer burn heretics.

Freeman Dyson