The introduction challenges the view of the history of science that predominated before publication of The Structure of Scientific Revolutions in 1962. That view held science to be a sequence of datable discoveries, inventions, and theories. It served a small but attitude-building function in science education because it formed part of the received knowledge in textbooks. Textbooks covered contemporary knowledge but not its development, seldom explaining scientific history in depth. Historians such as Alexander Koyré, Kuhn points out, were unable to support the development-by-accumulation view of science textbooks because it was sometimes impossible to determine precisely who made a discovery or when. If such questions as who or when were not always relevant, then a continuous, orderly development is at best a conveniently fictional image of science. Kuhn promises that his book will offer a new image drawn from a close examination of history.

In the first chapter, Kuhn argues that the methods of science alone cannot guarantee a unique answer to a question about nature. A researcher who is versed in the standards of evidence and logic in science but who is not trained in a particular discipline such as chemistry might devise any number of mutually incompatible answers to a problem in chemistry by applying standard scientific techniques. It is prior experience in a discipline, gained from scientists’ education and their professional careers, that guides a researcher to an answer that is useful to the discipline and compatible with it. Therefore, specialized training helps determine the types of questions that scientists will ask about the aspect of nature they study and the sorts of answers that they are likely to produce.