Treatise on Toleration

In 1762 Jean Calas, a merchant from Toulouse, was executed after being falsely accused of killing his son. As it became clear that Calas was in fact persecuted for being a Protestant, Voltaire began a campaign to get his sentence overturned – and in the process made the case for some of the most important values upheld by the Enlightenment, from religious tolerance to freedom of thought. Treatise on Toleration is the story of this case and a screed against fanaticism – a book that is as fresh and urgent today as it was when it was first published in 1763.