Russell’s teapot is an analogy, formulated by the philosopher Bertrand Russell (1872–1970), to illustrate that the philosophic burden of proof lies upon a person making unfalsifiable claims, rather than shifting the burden of disproof to others.
Russell specifically applied his analogy in the context of religion. He wrote that if he were to assert, without offering proof, that a teapot, too small to be seen by telescopes, orbits the Sun somewhere in space between the Earth and Mars, he could not expect anyone to believe him solely because his assertion could not be proven wrong.
Russell’s teapot is still invoked in discussions concerning the existence of God, and has had influence in various fields and media.
In an article titled «Is There a God?» commissioned, but never published, by Illustrated magazine in 1952, Russell wrote:
Many orthodox people speak as though it were the business of sceptics to disprove received dogmas rather than of dogmatists to prove them. This is, of course, a mistake. If I were to suggest that between the Earth and Mars there is a china teapot revolving about the sun in an elliptical orbit, nobody would be able to disprove my assertion provided I were careful to add that the teapot is too small to be revealed even by our most powerful telescopes. But if I were to go on to say that, since my assertion cannot be disproved, it is intolerable presumption on the part of human reason to doubt it, I should rightly be thought to be talking nonsense. If, however, the existence of such a teapot were affirmed in ancient books, taught as the sacred truth every Sunday, and instilled into the minds of children at school, hesitation to believe in its existence would become a mark of eccentricity and entitle the doubter to the attentions of the psychiatrist in an enlightened age or of the Inquisitor in an earlier time.
In 1958, Russell elaborated on the analogy:
I ought to call myself an agnostic; but, for all practical purposes, I am an atheist. I do not think the existence of the Christian God any more probable than the existence of the Gods of Olympus or Valhalla. To take another illustration: nobody can prove that there is not between the Earth and Mars a china teapot revolving in an elliptical orbit, but nobody thinks this sufficiently likely to be taken into account in practice. I think the Christian God just as unlikely.
Other thinkers have posited non-disprovable analogies, such as J. B. Bury in his 1913 book, History of Freedom of Thought:
Some people speak as if we were not justified in rejecting a theological doctrine unless we can prove it false. But the burden of proof does not lie upon the rejecter…. If you were told that in a certain planet revolving around Sirius there is a race of donkeys who speak the English language and spend their time in discussing eugenics, you could not disprove the statement, but would it, on that account, have any claim to be believed? Some minds would be prepared to accept it, if it were reiterated often enough, through the potent force of suggestion.
Astronomer Carl Sagan in his 1995 book The Demon-Haunted World offered a similar non-disprovable analogy called the Dragon in the Garage as an example of skeptical thinking. If Sagan claimed there was a dragon in his garage, you would wish to verify it for yourself but if Sagan’s dragon was impossible to detect:
Now, what’s the difference between an invisible, incorporeal, floating dragon who spits heatless fire and no dragon at all? If there’s no way to disprove my contention, no conceivable experiment that would count against it, what does it mean to say that my dragon exists?