Nations have always been conscious of the utility of acquiring general beliefs, and have instinctively understood that their disappearance would be the signal for their own decline. In the case of the Romans, the fanatical cult of Rome was the belief that made them masters of the world, and when the belief had died out Rome was doomed to die. As for the barbarians who destroyed the Roman civilisation, it was only when they had acquired certain commonly accepted beliefs that they attained a measure of cohesion and emerged from anarchy.
Plainly it is not for nothing that nations have always displayed intolerance in the defence of their opinions. This intolerance, open as it is to criticism from the philosophic standpoint, represents in the life of a people the most necessary of virtues. It was to found or uphold general beliefs that so many victims were sent to the stake in the Middle Ages and that so many inventors and innovators have died in despair even if they have escaped martyrdom. It is in defence, too, of such beliefs that the world has been so often the scene of the direst disorder, and that so many millions of men have died on the battlefield, and will yet die there.
There are great difficulties in the way of establishing a general belief, but when it is definitely implanted its power is for a long time to come invincible, and however false it be philosophically it imposes itself upon the most luminous intelligence. Have not the European peoples regarded as incontrovertible for more than fifteen centuries religious legends which, closely examined, are as barbarous[21] as those of Moloch? The frightful absurdity of the legend of a God who revenges himself for the disobedience of one of his creatures by inflicting horrible tortures on his son remained unperceived during many centuries. Such potent geniuses as a Galileo, a Newton, and a Leibnitz never supposed for an instant that the truth of such dogmas could be called in question. Nothing can be more typical than this fact of the hypnotising effect of general beliefs, but at the same time nothing can mark more decisively the humiliating limitations of our intelligence.