A. C. Grayling’s lucid and stimulating books, based on the idea that philosophy should engage with the world and make itself useful, invariably cause discussion. The Challenge of Things joins earlier collections such as The Reason of Things and Thinking of Answers, collecting Grayling’s recent writings on the world in a time of war and conflict. In describing and exposing the dark side of things, he also explores ways out of the habits and prejudices of mind that would otherwise trap us forever in the deadly impasses of conflicts of all kinds. Whether he is writing about the First World War and its legacy, free speech, the advantages of an atheist prime minister or the role of science in the arts, his essays are always enlightening, enlivening, and hopeful.