Works on Āyurveda (science of health and longevity) generally deal with eight subjects, one of which is ‘bhūtavidyā.’ It is the ancient equivalent of the modern psychiatry. Mental disorders, it was believed, were caused by bhūtas or malevolent spirits. The remedies recommended were prayers, oblations, exorcism as also some drugs.
See also ĀYURVEDA.
Bhūtavidyā is one of the nineteen branches of Knowledge (vidyās) mentioned in the Chāndogya Upaniṣad (7.1.2). It is, perhaps, the science and art of involving, inviting or controlling the goblins and disembodied spirits.
Spirit worship was and is quite rampant in tribal and semitribal societies of India.
See also BHŪTA.