"Most people," observes the great psychologist, Carl Jung, "confuse "self-knowledge" with knowledge of their conscious ego personalities. Anyone who has ego-consciousness at all takes it for granted that he knows himself. But the ego knows only its own contents, not the unconscious and its contents."
"People," he points out, "measure their self-knowledge by what the average person in their social environment knows of himself, but not by the real psychic facts which are for the most part hidden from them. In this respect the psyche behaves like the body with its physiological and anatomical structure, of which the average person knows very little too. Although he lives in it and with it, most of it is totally unknown to the layman, and special scientific knowledge is needed to acquaint consciousness with what is known of the body, not to speak of all this is not known, which also exists."
"In this broad band of unconsciousness, which is immune to conscious criticism and control," he warns, "we stand defenseless, open to all kinds of influences and psychic infections. As with all dangers, we can guard against the risk of psychic infection only when we know what it is that is attacking us, and how, where and when the attack will come. Since self-knowledge is a matter of getting to know the individual facts, theories help very little in this respect. For the more a theory lays claim to universal validity the less capable it is of doing justice to the individual facts."
[Jung, "The Undiscovered Self," pp. 14-16.]
In "How To Know God: The Yoga Aphorisms of Patanjali" (written with Christopher Isherwood), Swami Prabhavanada notes that "(t)he external world even in its most beautiful appearances and noblest manifestations, is still superficial and transient. It is not the basic Reality. We must look through it, not at it, in order to see the Atman" (or true nature of our being). In short, we need to be "in the world" but not "of the world," as great sages and philosophers have told us since time immemorial.
"The mind of the truly illumined man is calm," Prabhavananda observes, "not because he is selfishly indifferent to the needs of others, but because he knows the peace of the Atman within all things, even within the appearance of misery, disease, strife and want."
[Isherwood and Prabhavananda, "How to Know God," p. 24.]
But how to know this non-conflictive and acceptive consciousness of our inner being? Through introspection, self-examination and meditation is the answer found in virtually all traditions.
"(M)editation," Prabhavananda observes, "is evolution in reverse. Meditation is a process of devolution. Beginning at the surface of life," he explains, "the meditative mind goes inward, seeking always the cause being the appearance, and then the cause behind the cause, until the innermost Reality is reached."
[Isherwood and Prabhavananda, "How to Know God," p. 41.]
Thus, to "Know Thyself!" one must move beyond the small "self" of the ego to the transcendental "Self" of one's own inner being.