Servetus, Michael (1511–1553)

Spanish Anabaptist theologian and physician. He was a pioneer in the study of the circulation of the blood and found that it circulates to the lungs from the right chamber of the heart. He was, however, as noted for his death as for his life: passing through Calvin's Geneva, he was arrested for his unorthodox views on the Trinity (expressed in his treatise On the Errors of the Trinity (1531)). After Servetus had been found guilty of heresy, Calvin had him burnt.