The human enhancement debate has over the last few decades been concerned with ethical issues in methods for improving the physical, cognitive, or emotive states of individual people, and of the human species as a whole. Arguments in favour of enhancement defend it as a paradigm of rationality, presenting it as a clear-eyed, logical defence of what we stand to gain from transcending the typical limits of our species. If these arguments are correct, it appears that adults should in principle (...) be able to make rational and informed decisions about enhancing themselves. In this paper, however, we suggest that a rational and informed choice to enhance oneself may in some cases be impossible. Drawing on L. A. Paul’s work on ‘transformative experience’, we argue that some enhancements—such as certain moral or cognitive modifications—may give rise to unbridgeable epistemic gaps in key domains. Importantly, such gaps could prove to be not merely contingently unbridgeable due to a lack of information at a given moment, but radically unbridgeable, making someone in a non-enhanced state inherently unable to conceive of what it would be like to be enhanced in a particular way. Where this experience is key to understanding what values are being pursued by the enhancement itself, it may prove impossible for a person to be sufficiently informed, and to make a rational decision about whether or not to enhance herself. This poses a challenge for human enhancement proponents in general, and for transhumanists in particular. (shrink)

Dementia patients in the moderate-late stage of the disease can, and often do, express different preferences than they did at the onset of their condition. The received view in the philosophical literature argues that advance directives which prioritize the patient’s preferences at onset ought to be given decisive moral weight in medical decision-making. Clinical practice, on the other hand, favors giving moral weight to the preferences expressed by dementia patients after onset. The purpose of this article is to show that (...) the received view in the philosophical literature is inadequate and is out of touch with real clinical practice. I argue that having dementia is a cognitive transformative experience and that preference changes which result from this are legitimate and ought to be given moral weight in medical decision-making. This argument ought to encourage us to reduce our confidence in the moral weight of advance directives for dementia patients. (shrink)