Thomas S. Kuhn (1922–1996) exerted a strong force on intellectual discourse in the last third of the 20th century, by the publication of a book only 200 pages long. Why did Kuhn’s publications in his own primary field, history of science, have so little impact on that field? Was The Structure of Scientific Revolutions so successful in accelerating the trend toward social history of science that his own internalist work seemed outmoded? Kuhn wrote incisive articles on a wide range of topics including Robert Boyle and structural chemistry, energy conservation as an example of simultaneous discovery, the Cagnard engine, and the historiography of science, as well as a book on the Copernican Revolution; they are rarely cited by historians of science. His most important historical contribution in later years was in the history of quantum theory; he led a project to collect and preserve source materials, and published a monograph on the origin of the quantum hypothesis. Why does he receive almost no recognition for his remarkable work on the history of quantum physics? Does everyone still believe (in spite of Kuhn) that Planck introduced a physical quantum discontinuity in 1900?