Every branch of human knowledge, if traced up to its source and final principles, vanishes into mystery.
If a man dreams that he has committed a sin before which the sun hid his face, it is often safe to conjecture that, in sheer forgetfulness, he wore a red tie, or brown boots with evening dress.
It is all nonsense, to be sure and so much the greater nonsense inasmuch as the true interpretation of many dreams - not by any means of all dreams - moves, it may be said, in the opposite direction to the method of psycho-analysis.
Now, everybody, I suppose, is aware that in recent years the silly business of divination by dreams has ceased to be a joke and has become a very serious science.