If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind… — John Stuart Mill
If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind.
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More from this book
No one can be a great thinker who does not recognise, that as a thinker it is his first duty to follow his intellect to whatever conclusions it may lead...Not that it is solely, or chiefly, to form great thinkers, that freedom of thinking is required. On the contrary, it is as much and even more indispensable to enable average human beings to attain the mental stature which they are capable of.
I regard utility as the ultimate appeal on all ethical questions; but it must be utility in the largest sense, grounded on the permanent interests of man as a progressive being.
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.

