The whiteboard in John Harris’s office declares: “John is cool.” Many hold a different opinion of one of the most controversial philosophers in Britain. Here are some of his views: abortion and euthanasia are both fine, desirable even; parents should be allowed to create designer or cloned babies; there’s nothing wrong with a drug-fuelled Olympics; scientists and medics should strive to make us immortal, even on a crowded planet; our bodies should be routinely plundered after death for organs, even if the dead and bereaved do not wish it; it is morally justified to compel people to participate in scientific trials, just as we compel them to do jury service.

Harris believes in plain speaking. Every argument, he suggests, should be reduced to its least palatable form to see if it is ethically digestible: “I believe there is a moral imperative to describe things in their most uncongenial way, to see if we really could become comfortable with them. For example, when I defend abortion, I don’t insist on calling it termination of pregnancy. I’m prepared to say that I believe in the killing of unborn children.” No wonder Harris, the Sir David Alliance Professor of Bioethics at Manchester University, attracts hate mail and death threats from the pro-life lobby, even as he insists that it is he who is the real pro-lifer.

Now he has gone to town on his pro-life convictions in a compelling new book, which argues that we are morally obliged to take whatever steps we can – as parents, as citizens, as scientists – to make life better and longer for ourselves and our children. While society does so much to save life – think of how staunchly we defend threatened A&E units – we never stop to think that saving life is, in reality, postponing death.

If it is right to save life, Harris says, it is right to postpone death ad infinitum by stemming the flow of diseases that carry us to the grave. We should engineer ourselves to be free of such curses as cancer and dementia, instead of believing that they are acceptable inevitabilities of human life. And we should make any such technology available as soon as we can, even if it means the human race initially splitting into the strong, clever, beautiful, immortal haves and the dumber, disease-ridden have-nots.

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Background

• Legalised euthanasia safer

• US phone firm bans abortion rights messages

• You’re taking liberties with our DNA, m'lud

• Prisoners of our genes?

• Doing a ton with ease?

Harris denies advocating the pursuit of perfection; instead, he frames it as the pursuit of a life emptied of harms and overflowing with benefits. There is, however, the minor matter of the book’s arresting front cover, which will only fuel suspicions that Harris has a more sinister agenda. It is a bold, art-comic depiction of a muscled arm locked in a bicep curl, signifiying strength, power and dominance. It looks, I suggest to Harris, a mite Aryan. He shakes his head: “There are no lessons to be learnt from the Nazi period about the legitimacy of human enhancement. The Nazis weren’t concerned with enhancing the Aryan race; they just wanted to wipe out the Jews, gypsies and others they didn’t like.

“The truth is, the publishers and my wife were very keen on this cover. I wanted The School of Athensby Raphael instead. The publishers thought that would be disastrous because it wouldn’t sell any books.”

So the bicep curl won? “Of course. I write books to be read; I’m not ashamed of that.”

We meet in Harris’s university office in central Manchester. He is dapper and smiling, tie-less in a pinstriped suit and looks a decade younger than his 62 years (he’d like to live for a few million more, which we’ll come to later).

Born in 1945 to Jewish parents, he has risen above unpromising beginnings – orphaned at 13, denigrated by his headmaster at 16 as “too stupid to do A-levels” – to become one of our most prominent contemporary philosophers. He lectures, writes books, is a master of the radio soundbite; he is a member of the Human Genetics Commission and an adviser to the Government on the potential moral quandaries posed by a flu pandemic (eg, compulsory quarantine). He jointly edits the Journal of Medical Ethics. His work is unusually accessible and leavened with kindly humour.

Less benignly, he has been painted as one of a group of philosophers, including Ronald Dworkin and Peter Singer, responsible for nurturing a “culture of death” through his stance on abortion and euthanasia. His guiding principles are libertarianism – that people should be free to do as they wish, provided it doesn’t harm others – and utilitarianism, which is why he thinks that the living have a right to the organs of the dead.

What does he mean by “better people”? “I mean better in the ways we want to be better. Most people value health, attractiveness, knowledge, having a good memory. It is better to have strengths in those areas than weaknesses.” Ah, he mentions aesthetics. Research shows that prettier, taller people have happier, more successful lives. Does that mean we are morally obliged to produce not just healthy children but beautiful children?

“There are some goods, or qualities, that are so important to have and so disastrous to lack that they constitute a really powerful moral obligation. There are other goods that are marginal, such as aesthetics, except in the case of serious deformities. For example, given how much people value life, to protect them from premature death or give them a longer healthier life expectancy seems to me a powerful obligation. To make someone marginally more attractive is not an obligation but something we have moral reasons to do.”

Likewise, if pills could make children smarter in a safe way, he thinks we would be dumb not to use them. He says: “You have good moral reasons to advantage your children if you can, and good moral reasons to avoid failing to do so. I see enhancing a child as on a continuum with, say, taking folic acid and avoiding alcohol during pregnancy. These are things that decent, sensible parents do to protect their children.” He points out that we are already enhanced humans – by such advances as vaccination, which prevents us from succumbing to diseases that decimated our forebears. This is now lumped under the label of “medicine”; ditto for Ritalin, which modifies behaviour, and modafinil, a drug used to help people to stay awake. Even opera glasses are an enhancement, helping us to see farther than we can naturally. Genetic-based enhancements are simply another stop on the road to improving the lot of humankind.

Of course, the consequence of banishing the diseases of old age is a dramatic extension of lifespan. So be it, Harris says: “To quote a friend, I’d willingly sample a few million years and see how it goes.”

The idea, he believes, is not that enhancements – such as gene therapy to remove the threat of cancer, or so-called “smart pills” – give some a competitive advantage over others. The technologies should be available to all and should raise the baseline of human welfare just as compulsory schooling and public health policy aim to do.

“Certainly, sometimes we want competitive advantage – but for the enhancements I talk about the competitive advantage is not the prime motive. I didn’t give my son (he has a grown-up son, Jacob, to whom the book is dedicated) a good diet in the hope that others eat a bad diet and die prematurely. I’m happy if everyone has a good diet. The moral imperative should be that enhancements are generally available because they are good for everyone.” The only other route to equality, he says, is to level down so that everyone is as uneducated, unhealthy and unenhanced as the lowest in society – which is unethical. Even though we can’t offer a liver transplant to all who need them, he says, we still carry them out for the lucky few. Much better to try to raise the baseline, even if some are left behind.

And so we arrive at one possible consequence of the Harris worldview: a society in which some people can afford the enhancements needed to make their children disease-free and virtually immortal, and other people can’t. We will have moved to an era that he calls “enhanced evolution”, in which scientists can engineer, within a few decades, changes to the human genome that might otherwise have taken millions of years to achieve through natural evolution. In the span of that generation, the enhanced humans and normal humans might become so physiologically different that they would no longer be able to breed with each other.

This would create a split in our species (animals are defined as belonging to the same species if they can breed successfully with each other). We would no longer be a human race but a posthuman one.

“Some people are messianic about creating posthumans for the sake of it. But not me,” Harris clarifies. “I care about making people better, happier and longer-lived, and if the result is that we evolve into a different species, even to the point where except using reproductive technology we are not able to breed with our current species, I think, ‘Fine, let’s do it’.”

For him there is no particular virtue in human frailty, nothing particularly special about “humanness” (except our capacity for self-awareness, which is not threatened by opera glasses, vaccination or other enhancements) and no particular reason to preserve our stage of human evolution in aspic: “Can you imagine our ape ancestors getting together and saying, ‘This is pretty good, guys. Let’s stop it right here!’. That’s the equivalent of what people say today.”

In 2000, the American political economist and neo-conservative intellectual Francis Fukuyama argued that the human race needed to be saved from the clutches of maniacal biotechnologists intent on slowing down ageing and using genetic engineering to “disappear” familiar illnesses. Such moves, which Harris champions, would result in the loss of what Fukuyama called “factor X”, which could be described as the indefinable essence of being human (some suggest that factor X is another term for the equally nebulous concept of human dignity). Fukuyama’s argument is that human values are planted in human biology, and tinkering with the underlying biology could give rise to a dystopian nightmare. The problem with this, Harris writes, is that Fukuyama “gives no positive account of factor X which might persuade us either that it is worth preserving, or that if we lose it there will be hell to pay”.

Leon Kass, a highly influential American philosopher who has the ear of President Bush (and is believed to have persuaded the President to stop public funding of research using human embryos), is similarly repelled by Harris’s vision of a biotechnologyen-hanced future. Kass believes that to allow parents to design their children puts the new generation “at risk of despotic rule” by the previous generation. Harris contends that normal sexual reproduction already allows parents partly to “decide” their children’s genomes (through choice of sexual partner) and that parenting techniques do the rest. Despite our natures being moulded in this way, Harris says, these “natural” methods are not seen as a threat to human autonomy.

But Kass’s biggest crime, in Harris’s view, is to appeal to the “yuk factor” that some attach to perceived scientific interference with the human body. Kass wrote a widely quoted essay entitled The Wisdom of Repugnance, in which he argued that, in some cases, “repugnance is the emotional expression of deep wisdom, beyond reason's power fully to articulate it”. So even if you can’t say why an idea makes you shudder, Kass argued, your inability to explain it doesn’t invalidate it.

Harris doesn’t buy a jot of it, suggesting that repugnance spells neither wisdom nor a lack of it. “The fact that people can’t articulate the reasons for their distaste or revulsion doesn’t make it invalid,” Harris says. “But the fact that they feel revulsion doesn’t make it valid, either.

“Human history is littered with examples of things that we recognise now were inappropriate objects of revulsion. My father said it made him queasy to see women smoking. People said the same things about homosexuality and working women, and other races. Nobody would say today that those feelings were appropriate, even though they were powerfully felt by very large numbers of people, sometimes whole societies. We ought to have a rational caution about following the yuk factor because we know it has led us not only in the wrong direction but in a thoroughly corrupt direction.”

This is where, I think, Harris risks losing sympathy – while he may not feel repugnance at biotechnology, many people do. Harris argues that revulsion is neither valid nor invalid, then proceeds as if it is invalid.

Kass has said elsewhere that children should be “begotten” rather than “manufactured”. This fits with a rather Biblical view of the world in which God ordained Nature to be just so, and woe betide the scientist who would presume to do better.

Because of his difficult childhood, during which he was brought up largely by his older sister Gill, Harris has long abandoned God: “I’ ve been an atheist since I was 12, when my father died. It crystallised, for me, the fact that God was completely useless. My father was only 57, and my mother died a year later at 46. It seemed so obvious to me that what goes on in the world is incompatible with any God that anybody would wish to be on speaking terms with.”

And neither does Mother Nature deserve unyielding respect: “Medicine goes against nature – people naturallyfall ill and naturally die prematurely. If we believed in letting nature take its course, we would not practise medicine. It’s not that I despise nature; there’s no particular virtue in it. Sometimes it’s great, sometimes it’s crap.”

Harris continues: “The virtue of medicine is that it prevents harm and does good. That, I believe, is the virtue of enhancement. Enhancement shares exactly the same moral purpose as medicine and it’s likely to be at least, if not more, effective.”

With that, Harris is off to visit a ninety-something friend in hospital. If the world had proceeded as Harris would wish, how different his day might have been.

Enhancing Evolution: The Ethical Case for Making Better People, by John Harris, is published by Princeton University Press

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