This article examines a scientific controversy that raged for twenty years in physical organic chemistry during the second half of the twentieth century. After explaining what was at stake in the non-classical ion debate, I attempt—by examining the methodological reflections of some of the participants—a partial explanation of what sustained this controversy, particularly during its early stages. Instead of suggesting a breakdown of scientific method or the unavoidable historical contingency of scientific development, the endurance of this controversy instead reveals the (...) heuristic and pragmatic character of many of the explanations and predictions generated by theoretical organic chemistry. The results in this case are used to suggest a new role for the study of scientific controversies in revealing the economics of scientific inquiry. 1 Introduction2 The Non-classical Ion Debate3 Models for the 2-Norbornyl System4 Soft Theories and Reasoning by Analogy5 Scientific Controversy and the Non-classical Ion Debate6 Conclusion. (shrink)

In this essay I consider whether the theory of organic chemistry is reducible to the theory of quantum chemistry. Using philosophical machinery developed by James Woodward, I characterize the understanding provided by both theories. Then I argue that there are systematic reasons to suspect that quantum chemistry is incapable of supporting some of the significant explanations, predictions, and applications underwritten by an understanding of theoretical organic chemistry. Consequently, even should quantum chemistry be ‘reducible to’ quantum physics in some suitable sense, (...) there are good reasons to doubt that many of the significant results of organic chemistry could be reproduced by quantum chemistry alone. (shrink)