The first edition of this book profoundly challenged and divided students of philosophy, sociology, and the history of science when it was published in 1976. In this second edition, Bloor responds in a substantial new Afterword to the heated debates engendered by his book. "Bloor's book came out as a broadside that announced a new approach to the history and philosophy of science, an approach that became known as the strong programme.' . . . Now, any book published in history and philosophy of science must take Bloor and the strong programme into account."--Robert J. Richards, University of Chicago