Physicist Stephen M. Barr's lucid Student's Guide to Natural Science gives students an understanding, in broad outline, of the nature, history, and great ideas of natural science from ancient times to the present, with a primary focus on physics. Barr discusses the contributions of the ancient Greeks, the medieval roots of the scientific revolution of the seventeenth century, the role religion played in fostering the idea of a lawful natural order, and the major theoretical breakthroughs of modern physics. Throughout this thoughtful guide, Barr draws his readers' attention to the larger themes and trends of scientific history, including the increasing unification of our view of the physical world, in which the laws of nature appear increasingly to form a single harmonious mathematical edifice.