“He who knows only his own side of the case knows little of that. His reasons may be good, and no one may have been able to refute them. But if he is equally unable to refute the reasons on the opposite side, if he does not so much as know what they are, he has no ground for preferring either opinion... Nor is it enough that he should hear the opinions of adversaries from his own teachers, presented as they state them, and accompanied by what they offer as refutations. He must be able to hear them from persons who actually believe them...he must know them in their most plausible and persuasive form.”

John Stuart Mill

John Stuart Mill - “He who knows only his own side of...” 1

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“The nationalist not only does not disapprove of atrocities committed by his own side, but he has a remarkable capacity for not even hearing about them.”

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“Let the tutor make his charge pass everything through a sieve and lodge nothing in his head on mere authority and trust: let not Aristotle's principles be principles to him any more than those of the Stoics or Epicureans. Let this variety of ideas be set before him; he will choose if he can; if not, he will remain in doubt. Only the fools are certain and assured. For if he embraces Xenophon's and Plato's opinions by his own reasoning, they will no longer be theirs, they will be his. He who follows another follows nothing. He finds nothing; indeed he seeks nothing. We are not under a king; let each one claim his own freedom. Let him know that he knows, at least. He must imbibe their ways of thinking, not learn their precepts. And let him boldly forget, if he wants, where he got them, but let him know how to make them his own. Truth and reason are common to everyone, and no more belong to the man who first spoke them than to the man who says them later. It is no more according to Plato than according to me, since he and I understand and see it the same way. The bees plunder the flowers here and there, but afterward they make of them honey, which is all theirs; it is no longer thyme or marjoram. Even so with the pieces borrowed from others; he will transform and blend them to make a work of his own, to wit, his judgment. His education, work, and study aim only at forming this.”

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