The expansion of research and technical innovation in the neurosciences and allied disciplines over the past quarter century has given rise to myriad practical applications. The advent of new ways of detecting, measuring and manipulating aspects of human mental life and behavior in real-world social situations raises many ethical, moral, legal, and political questions. Fueled by hopes (on the one hand) about enhancing the quality of human life and by fears (on the other) of advancing psychotechnological dehumanization, there is, once again widespread and intense discussion about The meaning of human nature and the power of behavior control (Chorover, 1979). Several topics of contemporary neuroethical import will be surveyed in historical context. At least some of what is currently happening in this area will be shown to be not entirely unprecedented. However, a number of factors will also be identified that arguably introduce some new twists into traditional debates about the social and ethical implication...