I value a man mainly for his primary relations with truth, as I understand truth,—not for any secondary artifice in handling his ideas. Some of the sharpest men in argument are notoriously unsound in judgment. I should not trust the counsel of a smart debater, any more than that of a good chess-player.
 Oliver Wendell Holmes Sr., The Autocrat of the Breakfast-Table (1858). copy citation

Context

“The great minds are those with a wide span, which couple truths related to, but far removed from, each other. Logicians carry the surveyor’s chain over the track of which these are the true explorers. I value a man mainly for his primary relations with truth, as I understand truth,—not for any secondary artifice in handling his ideas. Some of the sharpest men in argument are notoriously unsound in judgment. I should not trust the counsel of a smart debater, any more than that of a good chess-player. Either may of course advise wisely, but not necessarily because he wrangles or plays well. The old gentleman who sits opposite got his hand up, as a pointer lifts his forefoot, at the expression, “his relations with truth, as I understand truth,”” source