Abstract

The launch of a revolutionary new scientific theory represents a rare occasion on which the apparently cumulative development of science might be influenced by particular events. Yet in the case of the Darwinian revolution it is often claimed that the theory of evolution by natural selection would have emerged more or less inevitably, given the scientific and cultural circumstances prevailing in mid-Victorian Britain. This essay challenges that claim by arguing that if Darwin had not been there to write his Origin of Species the subsequent development of biology would have occurred along a line that steadily diverged from the sequence of events we actually experienced. There would certainly have been an evolutionary movement in the late nineteenth century, but there would have been no selection theory to disturb the progressionist assumptions of the time. A totally non-Darwinian evolutionism might not have generated the challenges that led to the emergence of modern genetics in the early twentieth century, resulting in a very different understanding of the relationship between development, heredity, and environment.