The capacity for discerning the essential truth, in fact, is as rare among men as it is common among crows, bullfrogs and mackerel. The man who shows it is a man of quite extraordinary quality–perhaps even a man diseased…. All the durable truths that have come into the world within historic times have been opposed as bitterly as if they were so many waves of smallpox, and every individual who has welcomed and advocated them, absolutely without exception, has been denounced and punished as an enemy of the race.