"the power of preconceptions, of seeing in the anatomy what you expect to see. 'Contrary to Simons' and my original view, Ramapithecus itself does not have a parabolic dental arcade,' says Pilbeam. 'I 'knew' Ramapithecus, being a hominid, would have a short face and a rounded jaw-so that's what I saw.' Pilbeam and Simons were not uniquely guilty of this error. It occurs often, such is the uncertainty of interpreting fragmentary anatomy in fossils….
The clearest message of the Ramapithecus affair, however, is the power of preconceptions, which in this case led competent scientists to ignore the evidence of other competent scientists because the conclusions drawn from the evidence were at variance with established ideas. All scientists are guided to some degree by a set of assumptions, usually implicit rather than explicit. 'I try hard to detect them in my own thinking,' says Pilbeam, 'to isolate those assumptions that are not articulated because they are so 'obvious,' yet will seem so silly a few years from now. I am also aware of the fact that, at least in my own subject of paleoanthropology, 'theory'-heavily influenced by implicit ideas-almost always dominates 'data'…
Ideas that are totally unrelated to actual fossils have dominated theory building, which in turn strongly influences they way fossils are interpreted.'"
 "Rethinking Human Origins," in Discovery, vol. 13, pp. 5-6 (1978)
 Roger Lewin (noted science journalist), Bones of Contention (New York, NY: A Touchstone Book published by Simon & Schuster Inc., 1987), p. 28 citing "Myths and Methods in Anatomy," Journal of the Royal College of Surgeons of Edinburgh, vol. II, no. 2, pp. 87-114 (1966), p. 123 citing an interview with the author, Harvard, 23 Oct. 1984
 Lewin, pp. 126-127 citing "Rethinking Human Origins," in Discovery, vol. 13, pp. 8-9 (1978)