“Mental Transmutation” means the art of changing and transforming mental states, forms, and conditions, into others. So you may see that Mental Transmutation is the “Art of Mental Chemistry,” if you like the term—a form of practical Mystic Psychology.
The first of the Seven Hermetic Principles is the Principle of Mentalism, the axiom of which is “THE ALL is Mind; the Universe is Mental,” which means that the Underlying Reality of the Universe is Mind; and the Universe itself is Mental—that is, “existing in the Mind of THE ALL.”
Not only may the mental states, etc., of one's self be changed or transmuted by Hermetic Methods; but also the states of others may be, and are, constantly transmuted in the same way, usually unconsciously, but often consciously by some understanding the laws and principles, in cases where the people affected are not informed of the principles of self-protection.
The truth is, that beneath the material chemistry, astronomy and psychology (that is, the psychology in its phase of “brain-action”) the ancients possessed a knowledge of transcendental astronomy, called astrology; of transcendental chemistry, called alchemy; of transcendental psychology, called mystic psychology.
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