This book will deal with two tectonic movements in ideas, two truly major developments in intellectual history. One occurred in the years around 1600, and the other is happening right now. History doesn’t come with sharp edges, of course, but sometime around the turn of the seventeenth century there began what is often called the modern period, or modernity.[1] It lasted, roughly, until sometime in the late twentieth century. The vigorous youth of this period is often called the Enlightenment—a piece