The doctor learns that if he gets ahead of the superstitions of his patients he is a ruined man; and the result is that he instinctively takes care not to get ahead of them.
It's prudent to gain the whole world and lose your own soul. But don't forget that your soul sticks to you if you stick to it; but the world has a way of slipping through your fingers.
We must not stay as we are, doing always what was done last time, or we shall stick in the mud. Yet neither must we undertake a new world as catastrophic Utopians, and wreck our civilization in our hurry to mend it.