This text tries to shed some light on the origin of the idea of moral enhancement, on its epistemic and moral foundations. This requires a comparative analysis of similar ideas present in various trends of bioethics today - the analysis of the very roots of Poter?s global bioethics, the idea of moral enhancement, as well as the break between advocates of moral enhancement and John Harris, their transhumanist colleague, with whom they used (...) to share the same perspective. In this article we identify some basic starting points, similarities and differences between global bioethics and moral enhancement, and draw lines of demarcation between transhumanism and moral enhancement. (shrink)