Book excerpt: David Ricardo’s theories have been widely studied and discussed, including the prominent theory on comparative advantage. Ricardo and International Trade looks at the ongoing renaissance of the Ricardian international trade theory. The book’s interpretation brings fresh insights into and new developments on the Ricardian international trade theory by examining the true meaning of the ‘four magic numbers’. By putting together theories of comparative advantage and international money, the book attempts to elucidate Ricardo’s international trade theory in the real world. This book also features contributions from the Japanese perspective and compares Ricardian theories with those of his contemporaries, such as Malthus, Torrens and J. S. Mill. This book will be a valuable reference for researchers and scholars with interests in history of economic thought and international economics.