Our knowledge of human biology – in particular of genetics and neurobiology – is beginning to enable us to directly affect the biological or physiological bases of human motivation, either through drugs, or through genetic selection or engineering, or by using external devices that affect the brain or the learning process. We could use these techniques to overcome the moral and psychological shortcomings that imperil the human species.
The first thing to keep in mind is that this is not a unified category of things. We already use drugs in a limited way for moral enhancement -- caffeine to keep alert so that we can do our jobs, pychiatric treatments to compensate for various problems that can make a good human life more difficult, and so forth. It is completely unclear how we would go about engaging in moral enhancement on the basis of genetic engineering, however, and people have already tried the genetic selection or eugenics route and discovered that, even if, like Savulescu, you can get over the historical associations, there is no clear way to make it work in practice. Its influence over actual moral choices is obviously going to be as a general matter extremely indirect, and thus liable to be swamped out by other factors; voluntary genetic selection is quite slow and would require sustained effort over centuries; coercive genetic selection is obviously illiberal and leads to a completely understandable widespread resentment; and since there are a vast number of very different dimensions along with which one's moral life may be enhanced, and since we cannot select for them all simultaneously, it will necessarily be highly arbitrary and the choice in constant danger of political and social manipulation.
Savulescu and Perrson consider three facets of the case against putting much emphasis on this approach: that it is too slow, that it is subject to immoral capture, and that liberal democracy is a better approach. None of their responses to these are entirely adequate. To the first they say:
We do not dispute this. The relevant research is in its inception, and there is no guarantee that it will deliver in time, or at all. Our claim is merely that the requisite moral enhancement is theoretically possible – in other words, that we are not biologically or genetically doomed to cause our own destruction – and that we should do what we can to achieve it.
I'm not sure who holds that we are biologically or genetically self-destructive as a species. But this response massively underestimates everything across the board -- the sheer variety of things that fall into the category of 'moral bioenhancement' and thus our ability to make general claims here; our ability to know what moral enhancement would actually be required to give reasonable guarantee of "the basic ethical skills we need to ensure our own survival is not jeopardised" (which is not even necessarily possible, given that conditions of survival constantly change); and the ability of a something that is merely "theoretically possible" and future to lay much of a claim on our resources given that practically possible solutions to practical problems now are often already laying claim to those same resources here and now; and our ability to engage in the sort of massive multi-generational research that would be required for some of the moral bioenhancements Savulescu and Perrson have in mind. Far from providing even a gesture at an answer, their response to the problem really just underlines how serious it is for their position.
Likewise, their supposed answer to the bootstrapping problem -- how can we reasonably guarantee proper research and application, so that we actually enhance rather than deteriorate our moral abilities, especially given that the defects we are supposed to be eliminating will themselves be found throughout the whole phase of research and application? -- is simply to state it again in different words.
The problem is intensified, in fact, when we consider their response to the liberal democracy issue. They argue that, given "our parochial altruism and bias towards the near future," "there is good reason to believe that voters are more likely to get it wrong than right". This may be so, but the same biases will be operative throughout any sort of enhancement research, and the bigger the scale of the enhancement research, the more extensive their influence could become. Even if this weren't so, liberal democracy does not consist merely of voters voting; voting is itself merely one of the institutional processes of negotiation and deliberation by which things get accomplished in a free society. These very same institutional processes of negotiation and deliberation will necessarily be involved, often directly, in any extensive form of research.
It is a point that is worth emphasizing: large-scale scientific research is a social process depending heavily on other social processes for resources, and the only systems of processes that have any promise of being sufficiently stable for research on the scale that Savulescu and Perrson clearly have in mind and yet sufficiently resilient to resist domination by political interests are all liberal-democratic. You can organize large-scale research technocratically without dependence on the processes of a liberal democracy, but large-scale research of any kind is by its very size vulnerable to the interests that control the resources on which it depends. Technocracy without liberal democracy merely simplifies the processes of control -- it makes it easier for factions to dominate the whole by dominating certain key decision-making parts. If liberal democracy, then, cannot be reasonably trusted to deliver this sort of bioenhancement research, and to deliver it in a reasonably ethical way, then it simply cannot be done -- we know of no other way to maintain the social processes of research that could possibly provide a serious alternative. Scientific inquiry does not occur in a social void.