Hartsoeker's homonculus: a corrective note

Contrary to what is reported in many psychology texts, microscopists of the preformationist era in embryology, particularly Nicholas Hartsoeker and Antony van Leeuwenhoek, did not claim to have seen tiny homonculi, or fetuses, within human spermatozoa. This common misconception is based on the fact that both Hartsoeker and Leeuwenhoek had at one time included drawings of homonculi in their writings, but they did so only to suggest their possible appearance (Hartsoeker) or to refute allegations that they existed (Leeuwenhoek).