SummaryIn this article I argue that Darwin was the author, quite contrary to his original intentions, of a fundamental revolution in the theory of scientific knowledge. In 1838, in order to meet the anti-evolutionist challenge of his professional colleague, William Whewell, he began to sketch a transmutationist theory of the origin of human ideas which would explain the success of inductive science: its discovery of what Whewell and his contemporaries thought were necessary and certain truths. But though it explained how (...) scientific ideas originated, Darwin's theory implied also that theoretical certainty in science was impossible. Thus Darwin's evolutionism when combined with Whewell's a priorism led to a thorough-going fallibilism. This was worked out in detail by W. K. Clifford, a Cambridge evolutionist, Kantian and fallibilist. (shrink)

Historians should not use their own up-to-date methodologies to judge the rationality or correctness of the research strategies of scientists in history. For the history of science is, in part, the history of the rational growth of methodology and the historian's own up-to-date methodology is, in part, a product of the scientific revolutions of the past. Historians who use their own methodologies to judge the rationality of past research strategies are being too wise after the event. I show, using the (...) case of Charles Darwin, how we can judge the rationality and correctness of research strategies and revolutions without being too wise after the event. I do this by rejecting the idea that methodologies double as rationality theories and by drawing instead on Popper's competing view of rationality as critical debate. (shrink)