Despairing when his son Prince Antiochus was desperately ill, Seleucus, king of Syria, summoned the distinguished Greek physician Erasistratus (circa 330-255 BC) to diagnose his malady. Erasistratus and his colleague Herophilis from Alexandria in Egypt were renowned for their medical treatments that were based on their understanding of human anatomy and neuroanatomy, derived from dissecting the bodies of condemned criminals. Erasistratus is said to be the first physiologist, the first to appreciate that the heart is a pump, and the first to accurately describe the 1-way passage of blood through the heart's valves.2 Centuries before William Harvey described the circulation of the blood, Erasistratus recognized how veins and arteries were connected to the heart. Herophilus, his colleague in Alexandria, Egypt, timed the pulse, linked the pulse to the beating of the heart, and recognized its clinical importance. Erasistratus relied chiefly on hygiene, diet, baths, and exercise (rather than purgatives and bloodletting) as treatments. He anticipated psychosomatic medicine in observations grounded in anatomy and physiology and in hypothesis testing.