Conceptual Revolutions

In this path-breaking work, Paul Thagard draws on history and philosophy of science, cognitive psychology, and the field of artificial intelligence to develop a theory of conceptual change capable of accounting for all major scientific revolutions. The history of science contains dramatic episodes of revolutionary change in which whole systems of concepts have been replaced by new systems. For example, Copernicus's theory of the solar system supplanted Ptolemy's, and Darwin's theory of evolution by natural selection replaced earlier creationist views. Thagard provides a new and comprehensive perspective on the transformation of scientific conceptual systems. In addition to examining the Copernican and the Darwinian revolutions, Thagard turns his attention to the emergence of Newton's mechanics, Lavoisier's oxygen theory, Einstein's theory of relativity, quantum theory, and the geological theory of plate tectonics. He discusses the psychological mechanisms by which new concepts and links between them are formed, and advances a computational theory of explanatory coherence to show how new theories can be judged to be superior to previous ones. To assess whether the field of psychology has undergone revolutions similar to those in physics, chemistry, biology, and geology, he describes the nature and growth of behaviorism and cognitivism. Finally, he compares the transformations in scientific revolutions with the kinds of conceptual change that developmental psychologists have observed in children. Conceptual Revolutions is essential reading for historians and philosophers of science, and has important implications as well for research in cognitive science. It is clearly written and shouldbe accessible to anyone interested in problems of scientific change.