Hippocrates

View of a statue of Hippocrates.  Hippocrates (ca. 460–370 B.C.—the same era that the Parthenon was being constructed in Athens and Nehemiah was building the walls of Jerusalem) is considered to be the "father" of modern medicine who practiced at the Asclepion on Cos.

The famous "Hippocratic Oath" is attributed to him.  For a convenient presentation, with the actual text in Greek and English, see the article on Wikipedia.