For more than a thousand years, Christians denounced the Pythagoreans. They complained that Pythagoras did "ten thousand kinds of sorcery" healing the sick, predicting events, and stopping storms over rivers and seas so that his disciples might sail across them, like Jesus Christ. Some pagans said that Pythagoras was the son of the god Apollo and a human mother. Whereas Jesus died and resurrected only once, Pythagoras survived death multiple times as his soul was repeatedly reborn in other bodies. Whereas Jesus was dead for less than three days before his resurrection, Pythagoras allegedly spent two centuries in Hell, yet he returned to life. And similarly to the apostles of Jesus, some of the disciples of Pythagoras allegedly exorcised demons and resurrected the dead. But unlike the apostles, some of the Pythagoreans returned to life after death. Saint Hippolytus of Rome criticized this "alliance between heresy and the Pythagorean philosophy," and he denounced the "disciples not of Christ but of Pythagoras." The Pythagorean cosmology also troubled the Christians. The Pythagoreans said that that the infernal regions begin with the Milky Way, souls fall from it to Earth, and that animals' souls come from the stars. They said the Earth moves, and that stars and planets were other worlds. They said that souls live in those countless worlds, and that there were demons living on the Moon. They said that Pythagoras came from Jupiter and had lived on the Moon as a demon.

For centuries, the Christians rejected such "poisonous doctrines" and "devilish lies" of the Pythagoreans. The present book traces the development of Pythagorean beliefs about religion and astronomy, explaining how Church Fathers condemned such beliefs, and how that conflict reappeared in the Renaissance. This book is related to Burned Alive: Giordano Bruno, Galileo, and the Inquisition (Reaktion, 2018). While that book focused on Bruno, Galileo, and the Inquisition, this new book focuses on the religious conflicts between Christians and Pythagoreans. Historians know that the Pythagoreans were a secretive religious group, yet there was no historical account of how the early Christians criticized their evolving pagan beliefs and how such heresies resurfaced in the Copernican Revolution. How did the ancient Pythagorean religion relate to astronomy? How did it clash with Christianity?

Alberto A. Martinez is a professor of history at the University of Texas at Austin. He is the author of several books, including Burned Alive (2018), The Cult of Pythagoras: Math and Myths (Univ. of Pittsburgh Press, 2012), Science Secrets (Univ. of Pittsburgh Press, 2011), Kinematics: the Lost Origins of Einstein's Relativity (Johns Hopkins University Press, 2009), and Negative Math (Princeton University Press, 2005).