Ripley's tripartite system of race put him at odds both with others on the topic of human difference, including those who insisted that there was only one European race, and those who insisted that there were at least ten European races (such as Joseph Deniker, who Ripley saw as his chief rival). The conflict between Ripley and Deniker was criticized by Jan Czekanowski, who states, that ""the great discrepancies between their claims decrease the authority of anthropology"", and what is more, he points out, that both Deniker and Ripley had one common feature, as they both omitted the existence of an "Armenoid race", which Czekanowski claimed to be one of the four main races of Europe, met especially among the Eastern Europeans and Southern Europeans. Writing at a time when such racialist theories were widely accepted among academics, Ripley was the first American recipient of the Huxley Medal of the Royal Anthropological Institute in 1908 for his contributions to anthropology.