Ultimately, therefore, it is the relation of a class to society as a whole which maps out its part in the drama; and its success is determined by the breadth and variety of the interests, other than its own, which it is able to serve. Indeed, no policy of narrow class interest can safeguard even that interest well-a rule which allows of but few exceptions. Unless the alternative to the social setup is a plunge into utter destruction, no crudely selfish class can maintain itself in the lead.