“ A man who is willing to take another’s opinion has to exercise his judgment in the choice of whom to follow, which is often as nice a matter as to judge of things for one’s self. ”
 Oliver Wendell Holmes Sr., The Autocrat of the Breakfast-Table (1858). copy citation

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“For his part, common sense was good enough for him. Precisely so, my dear sir, I replied; common sense, as you understand it. We all have to assume a standard of judgment in our own minds, either of things or persons. A man who is willing to take another’s opinion has to exercise his judgment in the choice of whom to follow, which is often as nice a matter as to judge of things for one’s self. On the whole, I had rather judge men’s minds by comparing their thoughts with my own, than judge of thoughts by knowing who utter them. I must do one or the other. It does not follow, of course, that I may not recognize another man’s thoughts as broader and deeper than my own;” source