Challenges long-standing linear notions of scientific progress, arguing that transformative ideas don't arise from the day-to-day, gradual process of experimentation and data accumulation, but that revolutions in science, those breakthrough moments that disrupt accepted thinking and offer unanticipated ideas, occur outside of normal science.

This new edition of Kuhn's essential work includes an insightful introduction by Hacking, which clarifies terms popularized by Kuhn. Newly designed, with an expanded index, this edition will be eagerly welcomed by readers seeking to understand the history of our perspectives on science.