Abstract

When is it rational to undergo cognitive enhancement? In the case of what I’ll call massive cognitive enhancement, my answer is never. The reason is that one must base one’s decision to undergo massive cognitive enhancement on what I’ll call either phenomenal or non-phenomenal outcomes. If the former, the choice is not rational because massive cognitive enhancements are transformative and, I’ll argue with Paul (2015), transformative experiences cannot be chosen rationally. If the latter, the choice is not rational because it ought to be based at least partly on phenomenal outcomes. This argument, however, leaves open the idea that it may nonetheless be rational to choose massive cognitive enhancement for others—for example, one’s children. The article explores this possibility, arguing that choosing enhancement for others can be rational or moral, but not both.