The biomedical enhancement of moral status.

The biomedical enhancement of human capacities has emerged as one of the most philosophically invigorating areas of contemporary bioethical research. In exploring the ethical dimensions of emerging biotechnologies and human–machine interfaces, the literature on human enhancement has made significant contributions to traditional problems in moral philosophy. One such area concerns the enhancement of cognitive capacities that bear on moral status. Could biotechnological or other forms of neurocognitive intervention result in the creation of ‘postpersons’ who possess a moral status that is higher than that of ‘mere persons’? If the creation of postpersons with a higher moral status is indeed possible, is it morally wrong to bring this about? Nicholas Agar takes up these two questions in his Feature Article for this issue (see page 67, Editor ’s Choice), in which he defends affirmative answers to both. Most moral philosophers in the Kantian tradition would agree that were we to enhance the cognitive capacities of a nonrational sentient creature (such as a dog) so as to confer on it the psychological properties associated with personhood (such as practical rationality, selfawareness, interests that extend into the future, mutual accountability, and so on), we will have increased that creature’s intrinsic moral worth relative to nonrational sentient beings, and thus we will have enhanced its moral status. Virtually all parties to the moral status enhancement debate agree on this much. Why then would it not be similarly possible in principle to enhance the cognitive capacities of mere persons so as to create postpersons who possess a higher moral status than that of mere persons? While this may seem like a reasonable extrapolation from the first scenario, it is here that moral philosophical boats begin to diverge. Allen Buchanan was the first to address systematically the possibility of moral status enhancement and his work sets the backdrop for Agar ’s analysis. Buchanan argues that personhood is a threshold rather than scalar property that, once realised, confers a single tier of moral status on its bearers. His chief basis for this assertion is our commitment to the equal moral worth of persons, which entails that having more or less of X (where X is some cognitive property or cluster of properties necessary for personhood) has no bearing whatsoever on moral status, so long as X is realised to some minimal (non-zero) degree—and X is realised to some minimal degree, by definition, in all persons. The idea is powerful and seemingly persuasive: some people may be more rational, mutually accountable, deliberative, selfcontemplative or forward-looking than others, but this does not imply that such individuals have greater moral worth or possess rights that are more inviolable, on any plausible account of human rights. In some cases it may be difficult to determine whether a minimal degree of X is present in a given animal, but this is a separate epistemic question. Utilitarian moral philosophers, on the other hand, have an easier time justifying the differential weighting of mere person and postperson interests, respectively, according to the degree of X that they possess (for a discussion, see page 80). Agar’s target, however, is the Kantian approach. He argues that our commitment to the equal moral worth of persons is contingent on the existing range of human variation in X, and fails to extrapolate to a scenario involving vast disparities in cognitive abilities, such as the mixed society of mere persons and postpersons that he envisions. Agar contends that not only is it possible, but that we actually have affirmative reasons to believe (see below), that there are higher moral status thresholds than the one occupied by mere persons— thresholds that can be realised through radical cognitive enhancement. Yet a formidable challenge to the moral imagination remains: If there exists a higher threshold of moral status beyond that realised by mere persons, what sorts of cognitive capacities would give rise to this higher threshold? Would this simply involve greater degrees of the capacities canonically associated with personhood, or would it require, as suggested by Hauskeller (see page 76), an entirely novel cognitive ability, one that is different in kind from anything that mere persons possess? Agar punts on this question, though he has a good (if not entirely convincing) excuse: he contends that such a failure of imagination is to be expected, indeed is necessitated. For whatever property confers a higher moral status than that of mere persons, it will be a cognitive property; and because we, qua mere persons, lack that cognitive property, we cannot even conceive of what that property would be like, let alone describe its contours in any detail. Our position of epistemic ignorance vis-à-vis the defining properties of postpersonhood, Agar analogises, is akin to the futility of a non-rational sentient creature attempting to contemplate cognitive abilities associated with a higher moral status, such as rationality. This move might be too quick, however. We human mere persons can recognise and remark on the ability of toothed whales and microchiropteran bats to form detailed images through echolocation, even though we manifestly lack this ability. In a similar vein, why couldn’t we imagine nomically possible cognitive properties that we lack, such as visualising the universe in higher dimensions? Of course, there is no reason to think that abilities such as these have anything to do with moral status. But that is precisely the point. Our failure to imagine what properties might confer higher moral status on postpersons, if they do not simply involve more of X, is neither expected nor nomically necessitated. Nevertheless, Agar offers an inductive argument that such morally relevant properties exist. He notes that we currently have at least three widely accepted levels of moral status: non-sentient entities (with zero moral status), sentient non-persons (with intermediate moral status), and persons (with the currently highest level of moral status). We might add to this list (though not without controversy): some environmental ethicists hold that nonsentient living things posses a non-zero moral status, and many bioethicists have argued for a minimal moral status in the case of human embryos. Agar ’s induction proceeds as follows: given the plurality of putative moral statuses in the known universe, it seems likely that there are higher levels of moral status that are possible but currently not instantiated, or actual but currently unknown. To think otherwise, if I may offer an analogy on Agar’s behalf, would be akin to tallying the number of currently observable exoplanets and claiming, quite ludicrously, that there are precisely no more to be found. Note, however, the following: if Agar is right that we cannot conceive of the cognitive property that confers higher moral status, then it is impossible to know what sorts of cognitive enhancements would bring about higher moral status—the implication being that moral status enhancement could only occur as an accidental or incidental side effect of the enhancement of known, targeted properties of mere persons. If this is so, then Agar should be wary of even moderate