You must pursue facts for their own sake, but penetrated with a vivid sense of the problems of your own time. This is not a principle of perversion, but a principle of selection. You must have some principle of selection, and you could not have a better one than to pay special attention to the history of the social problems which are agitating the world now, for you may be sure that they are problems not of temporary but of lasting importance.
— Arnold Toynbee
