In the wind of the mind arises the turbulence called I. It breaks; down shower the barren thoughts. All life is choked. This desert is the abyss wher… - Aleister Crowley

Each being is, exactly as you are, the sole centre of a Universe in no wise identical with, or even assimilable to, your own. The impersonal Universe of Nature is only an abstraction, approximately true, of the factors which it is convenient to regard as common to all. The Universe of another is therefore necessarily unknown to, and unknowable by, you; but it induces currents of energy in yours by determining in part your reactions. Use men and women, therefore, with the absolute respect due to inviolable standards of measurement; verify your own observations by comparison with similar judgements made by them; and, studying the methods which determine their failure or success, acquire for yourself the wit and skill required to cope with your own problems.

Awake from dream, the truth is known: awake from waking. The truth is: The Unknown

It is a sort of sinister warning that there is some person or some thing in the Universe outside oneself: and the realisation of that is as frankly frightening as the other realisation, that one is eternally alone, is horrible.