Robert Broom (1866–1951) was one of South Africa's most distinguished scientists, a multi-faceted genius who contributed to many scientific disciplines, most notably to comparative anatomy, palaeontology and physical anthropology. This paper investigates the least known aspect of Broom's scientific output, his views on the mechanisms of evolutionary change. Broom believed that spiritual forces were behind evolution and that the creation of superhuman individuals and immortal souls was the ultimate end of evolution. This explanation was one of many similar attempts by scientists to incorporate into a theory of organic evolution some of the religious beliefs and values that seemed to be undermined by Darwinism. Speculative and unscientific from the perspective of contemporary science, Broom's theory of evolution gains different meaning if perceived within the intellectual context of the end of the nineteenth and the beginning of the twentieth century from which it originated.