Most people who live in open societies, especially in the West, take freedom of thought and the right to express that thought for granted. But through most of history, independent thinking, outside of the framework of social or religious convention, was discouraged and often actively persecuted. It is only recently that rational critiques of traditional perspectives have become an accepted part of public discourse. The struggle for independence of mind was many centuries in the making and involved repression, bloodshed, and martyrdom as well as breakthrough discoveries and heroic individuals who changed the way we look at the world, many times at risk to their own lives. One of the best surveys of this dramatic intellectual history is J. B. Bury’s Freedom of Thought. With striking eloquence and clarity of expression, Bury succinctly describes the struggle of reason in the search for truth from ancient times to the beginning of the 20th century. He leads the reader from the amazing florescence of rational inquiry in classical Greece, through the eclipse of free thought under the sway of religious authority during much of the Middle Ages, to the rediscovery of Greco-Roman philosophy in the Renaissance, and finally to the growth of rationalism during the Enlightenment and the scientific revolution. Along the way, Bury elucidates the key events that contributed to the modern rational comprehension of nature. He also provides thumbnail sketches of the many important persons —