"In a book the writer is often trying to persuade others of the result of his thinking; in a classroom the teacher ought to be trying to show others how one man thinks--and at the same time reveal what a fine feeling he gets when he does it well.  The teacher ought then, it seems to me, to make very explicit the assumptions, the facts, the methods, the judgments.  He ought not to hold back anything, but ought to take it very slowly and at all times repeatedly make clear the full range of moral alternatives before he gives his own choice"  (The Sociological Imagination, 1959, p. 79).