"Students of social science must fear popular approval; evil is with them when all men speak well of them. If there is any set of opinions by the advocacy of which a newspaper can increase its sales, then the student . . . is bound to dwell on the limitations and defects and errors, if any, in that set of opinions; and never to advocate them unconditionally even in an ad hoc discussion. It is almost impossible for a student to be a true patriot and have the reputation of being one at the same time."