The Hippocratic Oath is an oath historically taken by physicians. It is one of the most widely known of Greek medical texts. In its original form, it requires a new physician to swear, by a number of healing gods, to uphold specific ethical standards. The Oath is the earliest expression of medical ethics in the Western world, establishing several principles of medical ethics which remain of paramount significance today. These include the principles of medical confidentiality and non-maleficence. Although the ancient text is only of historic and symbolic value, swearing a modified form of the Oath remains a rite of passage for medical graduates in many countries.

The first paragraph of the oath:

"I swear by Apollo the Healer, by Asclepius, by Hygieia, by Panacea, and by all the gods and goddesses, making them my witnesses, that I will carry out, according to my ability and judgment, this oath and this indenture."

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