To every age its virtue. For the Greeks, courage; the Romans, duty; the Middle Ages, piety. Our virtue is industriousness, in the industrial age. (It is one that would have been incomprehensible to other times. The Greeks had a word for people who worked harder than anyone else: slaves.) It is the Protestant ethic, in other words, made general by the Victorians as the factories rose. That it is a virtue, not merely a value, is proved by the aura of righteousness that surrounds it.