Abstract
Interventions that modify a person’s motivations through chemically or physically influencing the brain seem morally objectionable, at least when they are performed nonconsensually. This chapter raises a puzzle for attempts to explain their objectionability. It first seeks to show that the objectionability of such interventions must be explained at least in part by reference to the sort of mental interference that they involve. It then argues that it is difficult to furnish an explanation of this sort. The difficulty is that these interventions seem no more objectionable, in terms of the kind of mental interference that they involve, than certain forms of environmental influence that many would regard as morally innocuous. The argument proceeds by comparing a particular neurointervention with a comparable environmental intervention. The author argues, first, that the two dominant explanations for the objectionability of the neurointervention apply equally to the environmental intervention, and second, that the descriptive difference between the environmental intervention and the neurointervention that most plausibly grounds the putative moral difference in fact fails to do so. The author concludes by presenting a trilemma that falls out of the argument.