A Constructive Survey of Upanishadic Philosophy c7.7.4

c7.7.4

and of the three Doshas, namely, wind, bile, and phlegm (S. 9. e); and in the Kaushitaki Upanishad we are told that the blood-vessels that go from the heart to the Puritat are as small as a hair divided thousand-fold, and that they are either tawny-coloured, or white,or dark, or yellow, or red (S. 9. f). With a little variation these blood-vessels were described, before the time of the Kaushitaki, in the Chhāndogya, as being tawny, white, blue, yellow and red (S. 9. g), and in the Bṛihadāraṇyaka as white, blue, tawny, green and red (S. 9. h). Whatever we may say about the "white" blood-vessels or "yellow" blood-vessels and the rest, it is evident that the authors of these passages knew at least the distinction between the blue and the red blood-vessels, a fact of great physiological importance. It was the study of Yoga which was the cause of the rise of physiological science which was the precursor of the later full-fledged systems of medicine.