by Tom Swift

Consciousness is a very recent acquisition and as such is still in an “experimental state” — frail, menaced by specific dangers, and easily injured. As a matter fact, one of the most common mental derangements among primitives consists in the “loss of the soul,” which, as the term indicates, means a noticeable dissociation of consciousness. …

What we observe in the seemingly remote sphere of the primitive mind has by no means vanished in our advanced civilization. Only too often, as I have said, the right hand does not know what the left is doing, and in a state of violent affect one frequently forgets who one is, so that people can ask: “What the devil has gotten into you?” We are possessed and altered by our moods, we can suddenly be unreasonable, or important facts unaccountably vanish from our memory. We talk about being able to “control ourselves,” but self-control is a rare and remarkable virtue. If you ask your friends or relatives they may be able to tell you things about yourself of which you have no knowledge. One almost always forgets or omits to apply to oneself the criticism that one hands out so freely to others, fascinated by the mote in one’s brother’s eye.

-C.G. Jung, The Undiscovered Self (1957)