A small conical gland (also called Conarium or Epiphysis Cerebri), about the size of a pea, located at the rear part of the forebrain. It secretes the hormone melatonin, which helps regulate the internal body clock or circadian rhythms. Melatonin secretion is affected by perception of light by the retina, and peaks in the evening and diminishes during the daytime.

Esoteric traditions link the pineal gland to the mysterious “third eye,” both in its physical sense and the extrasensory meaning. Helena P. BLAVATSKY affirms that the pineal gland used to be a physical eye, as evidenced by the New Zealand lizard called Hatteria punctata which still has this eye in an atrophied state.

She states that the pineal gland is connected with certain functions of the mind. It contains semi-transparent yellowish sand (acervulus cerebri) that has been observed by physiologists to be absent in children below six years old, congenital idiots and very old people. This is connected with the fact that the MANAS or Mind Ego “does not accomplish its full union with the child before he is six or seven years old” (CW XII:619). The Pineal Gland, she states, “is that which the Eastern Occultist calls Devāka, the ‘Divine Eye,’ or the ‘Third Eye.’ To this day, it is the chief and foremost organ of spirituality in the human brain.” It is “the very seat of the highest and divinest consciousness in man” (Key to Theosophy, Sec. 7).

The philosopher Rene Descartes believed that the pineal gland was the seat of the soul and that it connects the physical body and the mind, to which Blavatsky comments:

Unscientific as this may appear in our day of exact learning, Descartes was yet far nearer the occult truth than is any Hæckel. For the pineal gland, as shown, is far more connected with Soul and Spirit than with the physiological senses of man. (SD II:298)

The pineal gland, as well as the pituitary, are affected by intake of alcohol. Thus wine and liquors are absolutely prohibited among esoteric students, as they have a “directly pernicious effect upon the brain” and prevents the development of the “third eye” (CW XII:698, 496).

The Pineal Gland corresponds with Manas until it is touched by the vibrating light of Kunalinî, which proceeds from Buddhi, and then it becomes Buddhi-Manas. When Manas is united to Buddhi, or when Buddhi — and therefore Ātman also — is centred in Manas, it acts in the three higher cavities [of the brain], radiating and sending forth a halo of light, and this sometimes becomes visible in the case of very holy persons. The fires are always playing round the Pineal Gland; but when Kunalinī illuminates them for a brief instant, the whole universe is seen. (CW XII:697)

According to Annie Besant, the pineal gland becomes connected with one of the chakras in the astral body and through that with the mental body, and serves as a physical organ for the transmission of thought from one brain to another in telepathy (A Study in Consciousness, p. 259). See also PITUITARY GLAND.

V.H.C./P.S.H.

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