It's up to the person who advances a thesis to prove it.
Summary
Quotes
« Many orthodox people talk as if it were the job of skeptics to disprove dogmas rather than those who support them to prove them. This is obviously a mistake. If I were to suggest that between the Earth and Mars lies a porcelain teapot in elliptical orbit around the Sun, no one would be able to prove the contrary, provided I took the precaution of pointing out that the teapot is too small to be detected by our most powerful telescopes. But if I were to assert that, since my proposition cannot be disproved, it is intolerable for human reason to doubt it, I would immediately be considered a lunatic. However, if the existence of this teapot were described in ancient books, taught as a sacred truth every Sunday and inculcated in children at school, then any hesitation to believe in its existence would become a sign of eccentricity and would earn the skeptic the care of a psychiatrist in an enlightened age, or of the Inquisitor in more ancient times. »
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