The writer who is neither an advocate nor an opponent avoids slanting, except when he is seeking special literary effects. The avoidance of slanting is not only a matter of being fair and impartial; it is even more importantly a matter of making good maps of the territory of experience.
The profoundly biased individual cannot make good maps because he can see an enemy only as an enemy and a friend only as a friend. The individual with genuine skill in writing -- one who has imagination and insight -- can look at the same subject from many points of view. (p.49)