‘since traditions vary so much the world over and men’s opinions are so obviously opposed to one another and mutually destructive, and that not only among different nations but in one and the same state – for each single opinion we learn from others becomes a tradition – and finally since everybody contends so fiercely for his own opinion and demands that he be believed, it would plainly be impossible – supposing tradition alone lays down the ground of our duty – to find out what that tradition is, or to pick out truth from among such a variety, because no ground can be assigned why one man of the old generation, rather than another maintaining quite the opposite, should be credited with the authority of tradition or be more worthy of trust; except it be that reason discovers a difference in the things themselves that are transmitted, and embraces one opinion while rejecting another, just because it detects more evidence recognizable by the light of nature for the one than for the other. Such a procedure, surely, is not the same as to believe in tradition, but is an attempt to form a considered opinion about things themselves; and this brings all the authority of tradition to naught.’

John Locke, Essays on the Law of Nature