short transitional phase – it reaches out at the immediate environment, shaking, shaping and grinding to suit the form, the requirements, the wishes, and the whims of man. And in the long third phase, it will reach down into the secret places of the great universe of its own nature, and by aid of its ever growing intelligence and co‐operation, shape itself into an increasingly sublime creation – a being beside which the mythical divinities of the past will seem more and more ridiculous, and which setting its own marvellous inner powers against the brute Goliath of the suns and the planets, challenges them to contest.5
The case for positive engineering is not helped by adopting the tones of the mad scientist in a horror film. But behind the rhetoric is a serious point. If we decide on a positive programme to change our nature, this will be a central moment in our history, and the transformation might be beneficial to a degree we can now scarcely imagine. The question is: how are we to weigh this possibility against Tinbergen’s objection, and against other objections and doubts?
For the rest of this discussion, I shall assume that, subject to adequate safeguards against things going wrong, negative genetic engineering is acceptable. The issue is positive engineering. I shall also assume that we can ignore problems about whether positive engineering will be technically possible. Suppose we have the power to choose people’s genetic characteristics. Once we have eliminated genetic defects, what, if anything, should we do with this power? […]
The View that Overall Improvement is Unlikely or Impossible
There is one doubt about the workability of schemes of genetic improvement which is so widespread that it would be perverse to ignore it. This is the view that, in any genetic alteration, there are no gains without compensating losses. On this view, if we bring about a genetically based improvement, such as higher intelligence, we are bound to pay a price somewhere else: perhaps the more intelligent people will have less resistance to disease, or will be less physically agile. If correct, this might so undermine the practicability of applying eugenics or genetic engineering that it would be hardly worth discussing the values involved in such programmes.
This view perhaps depends on some idea that natural selection is so efficient that, in terms of gene survival, we must already be as efficient as it is possible to be. If it were possible to push up intelligence without weakening some other part of the system, natural selection would already have done so. But this is a naive version of evolutionary theory. In real evolutionary theory, far from the genetic status quo always being the best possible for a given environment, some mutations turn out to be advantageous, and this is the origin of evolutionary progress. If natural mutations can be beneficial without a compensating loss, why should artificially induced ones not be so too?
It should also be noticed that there are two different ideas of what counts as a gain or a loss. From the point of view of evolutionary progress, gains and losses are simply advantages and disadvantages from the point of view of gene survival. But we are not compelled to take this view. If we could engineer a genetic change in some people which would have the effect of making them musical prodigies but also sterile, this would be a hopeless gene in terms of survival, but this need not force us, or the musical prodigies themselves, to think of the change as for the worse. It depends on how we rate musical ability as against having children, and evolutionary survival does not dictate priorities here.
The view that gains and losses are tied up with each other need not depend on the dogma that natural selection must have created the best of all possible sets of genes. A more cautiously empirical version of the claim says there is a tendency for gains to be accompanied by losses. John Maynard Smith, in his paper on ‘Eugenics and Utopia’,6 takes this kind of ‘broad balance’ view and runs it the other way, suggesting, as an argument in defence of medicine, that any loss of genetic resistance to disease is likely to be a good thing: ‘The reason for this is that in evolution, as in other fields, one seldom gets something for nothing. Genes which confer disease‐resistance are likely to have harmful effects in other ways: this is certainly true of the gene for sickle‐cell anaemia and may be a general rule. If so, absence of selection in favour of disease resistance may be eugenic.’
It is important that different characteristics may turn out to be genetically linked in ways we do not yet realize. In our present state of knowledge, engineering for some improvement might easily bring some unpredicted but genetically linked disadvantage. But we do not have to accept that there will in general be a broad balance, so that there is a presumption that any gain will be accompanied by a compensating loss (or Maynard Smith’s version that we can expect a compensating gain for any loss). The reason is that what counts as a gain or loss varies in different contexts. Take Maynard Smith’s example of sickle‐cell anaemia. The reason why sickle‐cell anaemia is widespread in Africa is that it is genetically linked with resistance to malaria. Those who are heterozygous (who inherit one sickle‐cell gene and one normal gene) are resistant to malaria, while those who are homozygous (whose genes are both sickle‐cell) get sickle‐cell anaemia. If we use genetic engineering to knock out sickle‐cell anaemia where malaria is common, we will pay the price of having more malaria. But when we eradicate malaria, the gain will not involve this loss. Because losses are relative to context, any generalization about the impossibility of overall improvements is dubious.
The Family and Our Descendants
Unlike various compulsory eugenic policies, genetic engineering need not involve any interference with decisions by couples to have children together, or with their decisions about how many children to have. And let us suppose that genetically engineered babies grow in the mother’s womb in the normal way, so that her relationship to the child is not threatened in the way it might be if the laboratory or the hospital were substituted for the womb. The cruder threats to family relationships are eliminated.
It may be suggested that there is a more subtle threat. Parents like to identify with their children. We are often pleased to see some of our own characteristics in our children. Perhaps this is partly a kind of vanity, and no doubt sometimes we project on to our children similarities that are not really there. But, when the similarities do exist, they help the parents and children to understand and sympathize with each other. If genetic engineering resulted in children fairly different from their parents, this might make their relationship have problems.
There is something to this objection, but it is easy to exaggerate. Obviously, children who were like Midwich cuckoos, or comic‐book Martians, would not be easy to identify with. But genetic engineering need not move in such sudden jerks. The changes would have to be detectable to be worth bringing about, but there seems no reason why large changes in appearance, or an unbridgeable psychological gulf, should be created in any one generation. We bring about environmental changes which make children different from their parents, as when the first generation of children in a remote place are given schooling and made literate. This may cause some problems in families, but it is not usually thought a decisive objection. It is not clear that genetically induced changes of similar magnitude are any more objectionable.
A related objection concerns our attitude to our remoter descendants. We like to think of our descendants stretching on for many generations. Perhaps this is in part an immortality substitute. We hope they will to some extent be like us, and that, if they think of us, they will do so with sympathy and approval. Perhaps these hopes about the future of mankind are relatively unimportant to us. But, even if we mind about them a lot, they are unrealistic in the very long term. Genetic engineering would make our descendants less like us, but this would only speed up the natural rate of change. Natural mutations and selective pressures make it unlikely that in a few million years our descendants will be physically or mentally much like us. So what genetic engineering threatens here is probably doomed anyway. […]
Risks and
