Neuroethics applies cognitive neuroscience for prescribing alterations to conceptions of self and society, and for prescriptively judging the ethical applications of neurotechnologies. Plentiful normative premises are available to ground such prescriptivity, however prescriptive neuroethics may remain fragmented by social conventions, cultural ideologies, and ethical theories. Herein we offer that an objectively principled neuroethics for international relevance requires a new meta-ethics: understanding how morality works, and how humans manage and improve morality, as objectively based on the brain and social sciences. This (...) new meta-ethics will simultaneously equip neuroethics for evaluating and revising older cultural ideologies and ethical theories, and direct neuroethics towards scientifically valid views of encultured humans intelligently managing moralities. Bypassing absolutism, cultural essentialisms, and unrealistic ethical philosophies, neuroethics arrives at a small set of principles about proper human flourishing that are more culturally inclusive and cosmopolitan in spirit. This cosmopolitanism in turn suggests augmentations to traditional medical ethics in the form of four principled guidelines for international consideration: empowerment, non-obsolescence, self-creativity, and citizenship. (shrink)