Book excerpt: The dramatic collapse of the friendship between Rousseau and Hume, in the context of their grand intellectual quest to conquer the limits of human understanding. The rise and spectacular fall of the friendship between the two great philosophers of the eighteenth century, barely six months after they first met, reverberated on both sides of the Channel. As the relationship between Jean-Jacques Rousseau and David Hume unraveled, a volley of rancorous letters was fired off, then quickly published and devoured by aristocrats, intellectuals, and common readers alike. Everyone took sides in this momentous dispute between the greatest of Enlightenment thinkers. In this lively and revealing book, Robert Zaretsky and John T. Scott explore the unfolding rift between Rousseau and Hume. The authors are particularly fascinated by the connection between the thinkers' lives and thought, especially the way that the failure of each to understand the other--and himself--illuminates the limits of human understanding. In addition, they situate the philosophers' quarrel in the social, political, and intellectual milieu that informed their actions, as well as the actions of the other participants in the dispute, such as James Boswell, Adam Smith, and Voltaire. By examining the conflict through the prism of each philosopher's contribution to Western thought, Zaretsky and Scott reveal the implications for the two men as individuals and philosophers as well as for the contemporary world.