Up to 1616, when the Copernican theory of heliocentrism was prohibited, Galileo had never asserted its truth. But the pope and cardinals of the Roman Inquisition assumed that he had, and he was required to repudiate it. In contrast, Copernicus’s book was only lightly corrected and allowed to be read. Galileo continued his practice of not asserting the reality of heliocentrism in his Dialogue on the two world systems, but he was put on trial nevertheless, in 1633. However, instead of being charge