At the center of this philosophical tale by the acclaimed author of The Island at the Center of the World is a simple mystery: Where in the world is Descartes's skull, and how did it get separated from the rest of his remains? Following the journey of the great 17th-century French thinker's bones—over six countries, across three centuries, through three burials—after his death in Stockholm in 1650, Shorto also follows the philosophical journey into modernity launched by Descartes's articulation of the mind-body problem. Shorto relates the life of the self-centered, vainglorious, vindictive Descartes and the bizarre story of his remains with infectious relish and stylistic grace, and his exploration of philosophical issues is probing. But the bones are too slender to bear the metaphorical weight of modernity that he gives them. Their sporadic appearance in the tale also makes them a shaky narrative frame for the sprawling events Shorto presents as the result of Descartes's work: the Enlightenment, the French Revolution, the 19th century's scientific explosion, 21st-century battles between faith and reason. Given Shorto's splendid storytelling gifts, this is a pleasure to read, but ultimately unsatisfying.