Singham replies: If there is one thing that a study of the history of science teaches us, it is that the exact circumstances surrounding any specific scientific revolution—such as when exactly it occurred, who caused it, what factors triggered it, and how it gained acceptance—are unlikely to be answered to everyone’s satisfaction. A probe through the mists of time surrounding the events enriches one’s understanding of their complexity while seemingly not getting much closer to answering basic questions.
As Thomas Kuhn said,
[Historians of science] discover that additional research makes it harder, not easier, to answer questions like: When was oxygen discovered? Who first conceived of energy conservation? Increasingly, a few of them suspect that these are simply the wrong sorts of questions to ask…. [A] new theory, however special its range of application, is seldom or never just an increment to what is already known. Its assimilation requires the reconstruction of prior theory and the re-evaluation of prior fact, an intrinsically revolutionary process that is seldom completed by a single man and never overnight. 1
That is particularly true of the rich history of the Copernican revolution, even though the very accessibility of the competing models of heliocentrism and geocentrism, which can be understood by any layperson, fuels the feeling that getting at the truth of how this major change in our understanding of the solar system came about should be easy. But the truth here, like the truth elsewhere, is an elusive quantity.
The letter writers have raised important questions. Was Galileo’s discovery of Jupiter’s moons the decisive factor in the Copernican revolution gaining acceptance or just one of the many at play? Was the lack of acceptance of Aristarchus’s earlier heliocentric model an irrational, dogma-driven mistake that set back science for more than a thousand years, or was it a perfectly rational decision by his contemporaries based on the evidence available to them at the time? How important was technology to this scientific discovery? What role does aesthetics play in the acceptance of a new idea? Although these questions have no simple answers, investigating them, as the letter writers have done, can be highly rewarding and enlightening.
I am grateful to the writers for providing additional information about the events surrounding the Copernican revolution. For every letter submitted, there are likely dozens more that could have provided additional insights. The intent of my short article was not to provide the definitive account of such a major event in scientific history—an impossible task—but to make readers aware of the richness beneath the superficial stories handed down from generation to generation and to encourage teachers and students to explore the historical record more thoughtfully. I hope the contributions of the letter writers act as further stimuli to such an endeavor.
