The rediscovery of Idealism is an unmistakable feature of contemporary philosophy. Heavily criticised by the dominant philosophies of the twentieth century, it is being reconsidered in the twenty-first as a rich and untapped resource for contemporary philosophical arguments and concepts. This volume provides a comprehensive portrait of the major arguments and philosophers in the Idealist tradition. Idealism is philosophy on a grand scale, combining micro and macroscopic problems into systematic accounts of everything from the nature of the universe to the particulars of human feeling. In consequence, it offers perspectives on everything from the natural to the social sciences, from ecology to critical theory. Since Idealism is sometimes considered anti-science, however, this book places particular emphasis on its naturalism. Written for a broad readership, the book provides the fullest possible introduction to this most philosophical of philosophical movements.