The eight root downfall is to regard our physical bodies, or the skandhas or aggregates of our psycho-physical makeup, as impure and base. The reason why this is a root downfall is because Vajrayana sees everything as sacred. All appearances is a form of divinity, all sound is the sound of mantra, and all thought and awareness is the divine play of the transcending awareness, the Mahamudra experience. The potential for that sacredness exists within our present framework, so to speak, of the five skandhas. Acknowledging psycho-physical aggregates of an individual as the potential of the Buddhas of the five families, or the five elements, or the five feminine aspects, and so forth, is to recognize that, in tantra, the potential for the transformation exists within our present situation. To disparage that potential as something useless or impure or unwholesome is a root downfall, a basic contradiction, from the point of view of tantric practice.
-- from Foundations of Tibetan Buddhism by H.E. Kalu Rinpoche.
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