Science is, in my view, a social product. Accordingly, I believe that the central problem of the history of science is to understand how scientific knowledge has been generated and certified in different social contexts. The way in which I have chosen to approach this large and complex problem is through extended case studies. I started my career by examining how increasing social support for chemistry in Enlightenment Germany enabled chemists there to form one of the first national discipline-oriented communities. I also explored how this new community's structure and values shaped its struggle over and eventual acceptance of Lavoisier's revolutionary chemical theory.

Since completing this study, I have focused on interdisciplinary science. What conditions and considerations inspire, or impel, some scientists to venture outside the familiar ground of their own disciplines in quest of tools, insights, or problems? How have such scientists' backgrounds, contexts, and styles influenced the ways in which they have gone about pursuing their interdisciplinary projects? These are two of the issues that I have sought to illuminate with historical studies of sudden infant death syndrome and on solar and stellar physics. I plan to continue my study of interdisciplinarity by writing a book on the history of the stellar-energy problem from 1903, when physicists and astronomers began speculating about possible subatomic sources, to 1938-41, when Hans Bethe resolved the conundrum by making a compelling case that the energy radiated by ordinary stars originates in cyclic thermonuclear reactions.