OM Also AUM or pranava, Skt.; the most comprehensive and venerable symbol of spiritual knowledge in Hinduism. It also appears in Buddhism (particularly in Vajrayāna) as a mantric syllable, but has a different sense than in Hinduism. OM is a symbol of form as well as sound. This syllable is no magic word and is not even considered to be a word; rather it is a manifestation of spiritual power, a symbol that is to be found throughout the East, which betokens the presence of the absolute within māyā. The worlds of the physical, mental, and unconscious are represented in the letters of the syllable OM by three curves; the supreme consciousness is represented by the point outside and above the rest; this illuminates and reveals the other three. The form of OM is a concrete manifestation of the visible truth. No concept or object of this universe is independent. All are permutations of the one consciousness and participate in its nature to various degrees; in this way they are connected with one another.
The OM symbol consists of three curves, a semicircle, and a point and is an enclosed unit. The three curves are connected with one another and grow one out of the other. The point with the semicircle stands by itself. It rules the whole. The symbol stands for three states of consciousness—the waking state, the dream state, and the state of deep sleep—as well as the supreme consciousness or self, which observes and permeates these states. The semicircle under the point is not closed; it symbolizes the infinite and its openness indicates that finite thinking cannot grasp the depth and the height of the point.
The material world of the wakeful consciousness, the level of external activity and thus the most palpable, is symbolized by the large lower curve. The level of the dream state, subject to the stimulus not of external objects but only of mental representations, is symbolized by the second, small curve, which is, so to speak, between wakefulness and sleep. The upper curve symbolizes the unconscious, which we call deep sleep, but it is also a connective link, for it is closest to the point that represents absolute consciousness. The point is the absolute consciousness that illuminates and governs the three others; it is Turīya, “the fourth.” Without turīya, there would be no thinking, no symbol, and no universe. The point illuminates the three states. It itself lights by its own light and is only experienced by persons who have gone beyond the three curves and attained the point and merged with it. The point can be interpreted variously: as absolute consciousness, as witnessing consciousness behind body and thought, or as liberation from the world of appearance.
Western commentators have equated OM as aum with the three deities (trimurti); however this exposition is not sufficiently profound.
Source: The Encyclopedia of Eastern Philosophy and Religion: Buddhism, Hinduism, Taoism, Zen. Shambhala Publications, Inc.
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