The Lost Calculation
Introduction
India and Tibet are at the heart of the richest philosophical, medical, and astrological traditions known to humankind. India has especially influenced the Tibetan philosophical, medical, and astrological traditions, but if we view the Tibetan systems as being purely of Indian origin and influence then we simultaneously dismiss a wealth of knowledge. Students in these fields cannot afford to rely purely on Sanskrit texts of Indian origin if they hope to ascertain a complete portrait of the profound sciences they study. For many reasons, portions of Sanskrit texts have been either entirely lost or patched together over centuries, facing the misfortune of errors, misunderstandings, and corruption. The Tibetans have thus done a great service to Indian culture by translating a plethora of such texts into the Tibetan language, thereby preserving them.
Those who doubt that the Tibetans have indeed done so need only study the Sanskrit and Tibetan languages. Tibetan is derived from Sanskrit and it mirrors Sanskrit largely for the purpose of easily translating Sanskrit texts. The Tibetan language was, in fact, so well-structured upon Sanskrit that modern scholars have been able to translate Tibetan texts back into the original Sanskrit in cases where the original Sanskrit text has been entirely lost. However, in preserving the Indian texts they found to be of value, the Tibetans were not merely accepting the Indian paradigms--they were critically examining and improving upon what they found. A poor understanding of this leads to the common assertions people make of Tibetan culture when they state that Tibetan Medicine is nothing other than Indian Ayurveda, or that Tibetan Astrology is nothing other than a fusion of Indian and Chinese Astrology. There is no doubt of the Indian influence and foundation of these systems in Tibet, but the Tibetans have improved upon these systems and also brought the understanding of their own native culture (Bön) to it.
My purpose in stating this is due to the fact that there is currently great controversy amongst Vedic astrologers as to which zodiac to use (sidereal or tropical). Given that no existing text in the Vedic tradition has been able to offer irresolute proof that one should be used over the other, I have naturally turned to an Indian text in the Buddhist tradition that has been incorporated into the Tibetan astrological and yogic tradition: the Kālacakra Tantra. The Kālacakra Tantra, together with its commentary, Vimalaprabhā, constitute two 11th century texts that provide the foundation of Indian astrology in Tibet. What is interesting about these texts is that while they proceed directly from the Indian siddhāntas, they directly criticize and correct the perceived errors in calculation. I believe that the Kālacakra Tantra offers a revolutionary spirit and vision of clarity in times of naïve orthodoxy where the only absolute has become ambiguity itself. The import of my findings are therefore the proceeding content and significance of this essay.