The leading theoretical physicist Carlo Rovelli turns to the ancient Greek philosopher Anaximander—the author of the first scientific concept of how the world is structured—to trace the history of scientific thought. The author carefully reconstructs Anaximander’s theories based on what we know, paying special attention to their historical and philosophical context. In the book, descriptions of the earliest concepts of the world’s structure naturally intertwine with reflections by a prominent scientist of our time on the very nature of scientific thinking.