Galen (c.129-200 AD), Ancient Greek physician and anatomist, lecturing on anatomy in Rome, in the Temple of Peace, using animal skeletons (right). Galen came to Rome in 162 AD. He became physician to the emperor Marcus Aurelius, and gave public lectures and demonstrations in his native Greek. Galen's ideas would dominate western medicine for the next 1500 years. Artwork from the 19th century book Vies des Savants Illustres.