There is good reason for believing that the ancient Greeks derived much of their philosophy and religion from the Egyptians, who seem in their turn to have taken both in great measure from India. Says Elphinstone: “It is impossible not to be struck with the identity of the topics discussed by the Hindu philosophers with those which engaged the attention of the same class in ancient Greece, and with the similarity between the doctrines of schools subsisting in regions of the earth so remote from each other.”[230] Here we find the doctrines of the eternity of matter, the derivation of all souls from God and their return to Him, the doctrine of atoms and a whole system similar to that of Pythagoras. The Greek philosopher taught that intermediate between God and mankind are a host of aerial beings who exercise various influences on the condition of mankind and the affairs of the world. Enfield[231] and Stanley[232] say that Pythagoras learned his doctrine from the Magi or Oriental philosophers. Max Müller says that Zarathustra and his followers, the Zoroastrians, had been settled in India before they immigrated into Persia. “That the Zoroastrians and their ancestors started from India during the Vaidik period, can be proved as distinctly as that the inhabitants of Massilia started from Greece.... Many of the gods of the Zoroastrians come out ... as mere reflections and deflections of the primitive and authentic gods of _Veda_.”[233] The Hindus say that when their four immortal Vedas, named Rig, Yajur, Sáma, and Atharva, were originally given to man by Brahma, there was no disease or sin; but when mankind fell away from this virtuous and happy state, life was shortened and disease introduced. Brahma, in his compassion for the sufferings of mankind, then gave a second class of sacred books, the _Upavédas_; one of these, named _Ayur-Veda_, treats of the prevention and cure of diseases. Some say this work really came from Siva; it is the sacred medical authority of the Hindus, and is of the highest antiquity. It was originally of great length, but Brahma in mercy to mankind shortened it. Fragments now only remain, and these in the works of commentators. Two divisions treat of surgery. 1st, _Salya_ treats of the surgery of the removal of foreign bodies, pus, and the dead child from the uterus; of healing wounds caused by knives, etc.; of bandaging, operations, blistering, and the treatment of abscesses and inflammations. 2nd, _Sálákya_ treats of diseases of the eyes, ears, mouth, and nose. 3rd, _Káyachikitsá_ describes diseases affecting the whole body, as fevers, dysentery, etc. This section may be considered as constituting the practice of medicine. 4th, _Bhutavidya_ deals with the art of restoring the deranged faculties of the mind produced by demoniacal possession, as by the anger of the gods, devils, giants, or spirits of dead men. They can only be removed by prayers, medicines, ablution, and offerings to the offended deity.