Black Oxen by Gertrude Atherton

It seemed to Clavering that he had run the gamut of the emotions while listening to that brief biography, so sterilely told, but there had also been times when he had felt as if suspended in a void even while visited by flashes of acute consciousness that he was being called upon to know himself for the first time in his life. And in such fashion as no man had ever been called upon to know himself before.

There was no precedent in life or in fiction to guide him, and he had realized with a sensation of panic even while she talked that it was doubtful if any one had ever understood himself since the dawn of time. Man had certain standards, fixed beliefs, ideals, above all, habits -- how often they scattered to the winds under some unheralded or teratogenic stress. He had seen it more than once, and not only in war. Every man had at least two personalities that he was aware of, and he dimly guessed at others. Some were frank enough to admit that they had not an idea what they would do in a totally unfamiliar situation. Clavering had sometimes emblemized man and his personalities with the old game of the ivory egg. A twist and the outer egg revealed an inner. Another and one beheld a third. And so on to the inner unmanipulatable sphere, which might stand for the always inscrutable soul.