Whenever you read stories about identical twins separated at birth, they tend to follow the template set by the most remarkable of them all: the “two Jims”. James Springer and James Lewis were separated as one-month-olds, adopted by different families and reunited at age 39. When University of Minnesota psychologist Thomas Bouchard met them in 1979, he found, as a Washington Post article put it, both had “married and divorced a woman named Linda and remarried a Betty. They shared interests in mechanical drawing and carpentry; their favourite school subject had been maths, their least favourite, spelling. They smoked and drank the same amount and got headaches at the same time of day.” The similarities were uncanny. A great deal of who they would turn out to be appears to have been written in their genes.
Other studies at the world-leading Minnesota Center for Twin and Family Research suggest that many of our traits are more than 50% inherited, including obedience to authority, vulnerability to stress, and risk-seeking. Researchers have even suggested that when it comes to issues such as religion and politics, our choices are much more determined by our genes than we think.
Many find this disturbing. The idea that unconscious biological forces drive our beliefs and actions would seem to pose a real threat to our free will. We like to think that we make choices on the basis of our own conscious deliberations. But isn’t all that thinking things over irrelevant if our final decision was already written in our genetic code? And doesn’t the whole edifice of personal responsibility collapse if we accept that “my genes made me do it”? To address these concerns, we first need to look a bit more closely at what the experiences of identical twins really show.
Professor Tim Spector has been studying identical twins at King’s College London for more than 20 years. From the start of his research in the early 1990s, it became evident to Spector that identical twins were always more similar than brothers or sisters or non-identical twins. At the time, however, “social scientists hated the idea” that genes were an important determinant of who we were, “particularly in those rather controversial areas like IQ, personality and beliefs”. As “one of the many scientists who took the gene-centric view of the universe for granted”, Spector wanted “to prove them wrong, and to prove that there’s nothing that’s not genetic to some extent”. Today, he looks back on this as part of his “overzealous genetic phase”.
It is perhaps understandable that Spector got caught up in gene mania. The launch in 1990 of the Human Genome Project, which aimed to map the complete sequence of human DNA, came at the beginning of a decade that would mark the high point of optimism about how much our genes could tell us. Daniel Koshland, then editor of the prestigious journal Science, captured the mood when he wrote: “The benefits to science of the genome project are clear. Illnesses such as manic depression, Alzheimer’s, schizophrenia, and heart disease are probably all multigenic and even more difficult to unravel than cystic fibrosis. Yet these diseases are at the root of many current societal problems.” Genes would help us uncover the secrets of all kinds of ills, from the psychological to the physical.
Ten years later, Bill Clinton and Tony Blair were among the guests gathered to “celebrate the revelation of the first draft of the human book of life”, as Francis Collins, the director of the Human Genome Project, put it. “We try to be cautious on days like this,” said the ABC news anchor, “but this map marks the beginning of an era of discovery that will affect the lives of every human being, with implications for science, history, business, ethics, religion, and, of course, medicine.”
By that time, genes were no longer simply the key to understanding health: they had become the skeleton key for unlocking almost all the mysteries of human existence. For virtually every aspect of life – criminality, fidelity, political persuasion, religious belief – someone would claim to find a gene for it. In 2005 in Hall County, Georgia, Stephen Mobley tried to avoid execution by claiming that his murder of a Domino’s pizza store manager was the result of a mutation in the monoamine oxidase A (MAOA) gene. The judge turned down the appeal, saying that the law was not ready to accept such evidence. The basic idea, however, that the low-MAOA gene is a major contributing cause of violence has become widely accepted, and it is now commonly called the “warrior gene”.
In recent years, however, faith in the explanatory power of genes has waned. Today, few scientists believe that there is a simple “gene for” anything. Almost all inherited features or traits are the products of complex interactions of numerous genes. However, the fact that there is no one genetic trigger has not by itself undermined the claim that many of our deepest character traits, dispositions and even opinions are genetically determined. (This worry is only slightly tempered by what we are learning about epigenetics, which shows how many inherited traits only get “switched on” in certain environments. The reason this doesn’t remove all fears is that most of this switching on and off occurs very early in life – either in utero or in early childhood.)
What might reduce our alarm, however, is an understanding of what genetic studies really show. The key concept here is of heritability. We are often told that many traits are highly heritable: happiness, for instance, is around 50% heritable. Such figures sound very high. But they do not mean what they appear to mean to the statistically untrained eye.
The common mistake people make is to assume that if, for example, autism is 90% heritable, then 90% of autistic people got the condition from their parents. But heritability is not about “chance or risk of passing it on”, says Spector. “It simply means how much of the variation within a given population is down to genes. Crucially, this will be different according to the environment of that population.
Spector spells out what this means with something such as IQ, which has a heritability of 70% on average. “If you go to the US, around Harvard, it’s above 90%.” Why? Because people selected to go there tend to come from middle-class families who have offered their children excellent educational opportunities. Having all been given very similar upbringings, almost all the remaining variation is down to genes. In contrast, if you go to the Detroit suburbs, where deprivation and drug addiction are common, the IQ heritability is “close to 0%”, because the environment is having such a strong effect. In general, Spector believes, “Any change in environment has a much greater effect on IQ than genes,” as it does on almost every human characteristic. That’s why if you want to predict whether someone believes in God, it’s more useful to know that they live in Texas than what their genes are.
Statistical illiteracy is not the only reason why the importance of environmental factors is so often drowned out. We tend to be mesmerised by the similarities between identical twins and notice the differences much less. “When you look at twins,” says Spector, “the one thing that always seems to come out are the subconscious tics, mannerisms, postures, the way they laugh. They sit the same, cross their legs the same, pick up cups of coffee the same, even if they hate each other or they’ve been separated all their lives.” It’s as though we cannot help thinking that such things reflect deeper similarities even though they are actually the most superficial features to compare. If you can stop yourself staring at the similarities between twins, literally and metaphorically, and listen properly to their stories, you can see how their differences are at least as telling as their similarities. Far from proving that our genes determine our lives, these stories show just the opposite.
When Ann and Judy from Powys, mid-Wales were born in the 1940s, they were the last thing their working-class family with five children needed. So, identical or not, Ann and Judy were packed off to live with different aunts. After three months, Judy returned to her biological mother, as her aunt could not manage raising another child. But for the childless 50-year-old couple who took on Ann (without ever formally adopting her), the late opportunity for parenthood was a blessing and she stayed.
Ann and Judy, who are now well into retirement, told me their story in Ann’s home in Crickhowell on the edge of the Brecon Beacons, over coffee and home-made Welsh cakes. Their experience is a valuable corrective for anyone who has been impressed by tales of how identical twins show that we are basically nothing but the products of our genes.
Although the girls grew up in the same town, they ended up living in different areas and went to different schools. The two households in which Ann and Judy grew up were very different. Judy’s father drove trains inside the steelworks, and her mother, like most women at the time, did not have a job. The family lived in a basic two-up, two-down house with a toilet at the bottom of the garden. Judy’s four older brothers were all out working by the time she was five and she was left with her older sister Yvonne.
Ann was brought up in a newly built, semi-detached house, with a toilet indoors. Her father was also a manual labourer in the steelworks, but they were relatively well off, partly because they hadn’t had children but also because they were “very careful with money”. Ann recalled that “the sugar bowl was never filled so as not to encourage people to take too much”.
Where Judy told me she “was a street kid, always out”, Ann said she always had her “nose in a book because I was on my own”. And while Ann passed the 11-plus exam and got into the grammar school, Judy didn’t, and ended up at the secondary modern. Although, aged 15, Judy was offered a place at a grammar school, when she got there she found herself suddenly studying algebra and geometry in a class where everyone else had already being doing it for three years. Unsurprisingly she struggled. After four months, Judy quit and went to work in a furniture shop.
Ann, meanwhile, breezed through school, although she, too, left early because her now 66-year-old father was retiring. “I just felt that it wasn’t fair for me to stay on at school when they were on a pension,” she said. At 16, Ann began her white-collar job in the local council offices, not long after Judy had started working on the shop floor.
Although the twins’ paths had diverged up to this point, the next stage in the story is the moment where their stories converge in an uncanny way. Less than six months into her job, Ann got pregnant and quit. Two months later, Judy also got pregnant and quit the nursing course she was enrolled in. Not only that, but both fathers, soon husbands, turned out to be very violent.
However, the differences in what happened next are instructive. Ann didn’t stay married for long. “I left and went back home, and they were very supportive when they found out what was going on.” Judy, in contrast, stayed with her husband for 17 years. “I did leave him, mind, but I kept going back. I didn’t have the support. I had three children by the time I was 21.” Her mother was no help. “My mother’s attitude was, you made your bed, you lie on it,” Judy explained. Ann understands Judy’s acquiescence perfectly. “Imagine being at home, with three children, no qualifications, nothing on the horizon to see your life was going to get better, which I did have.”
The two only really started a proper sibling relationship after Ann read about the Minnesota University research in the paper and wrote to the university about her and her sister. When they were 48, they travelled together to Minnesota to meet scientists there. Now the twins are both retired. Judy says, “I think from where we started we’ve travelled the same distance.”
But there were important differences in how their lives went, and so too in the people they became. Most obviously, Ann has always had more money, but you can also see the effects of their different backgrounds on their health. “Judy’s had a hysterectomy, I haven’t,” says Ann. “Judy’s got a problem with her kidneys. I don’t. Judy’s got blood pressure, I haven’t. But she’s stronger than me.”
There are also differences in how they think and behave socially. Although their political views are very similar, Judy says, “I’m a Christian, well, probably agnostic, I think,” whereas Ann is “a confirmed atheist”. Ann also thinks she’s “much more diplomatic. Judy is just rude. That’s probably the educational background coming through. ‘Interfering’ is too strong a word, but Judy is more involved with her children and grandchildren in an advisory capacity, whereas I wouldn’t do that.” Much of this, they agree, is surely down to culture, with Ann being encouraged to adopt more genteel middle-class ways.
Ann and Judy’s story illustrates that our genes only set down what might be described as a field of possibilities. These set limits on what we are to become – so whatever our upbringings, most of us will tend towards introversion or extroversion, jollity or sobriety, facility with words or numbers. But this is far from the claim that we become is essentially written in our genes. Rather, various options are pencilled in, and our life experiences determine which get inked.
Tim Spector’s view that environment is almost always more influential than genes is clear in the case of Ann and Judy. The sisters shared the same genes but with a middle-class background Ann did better at school, earned more money and has enjoyed better health. Too much attention to genes blinds us to the obvious truth that access to financial and educational resources remains the most important determinant of how we fare in life.
Although being more middle class might improve your odds of success in life, other non-genetic factors play a huge role. Take the war babies Margaret and Eileen from Preston, Lancashire, another set of identical twins who were brought up in different families. Margaret’s adoptive parents owned their own house. Eileen’s toilet was at the bottom of the garden. And yet it was Margaret who flunked her 11-plus, simply out of nerves, while Eileen passed hers. Margaret’s adoptive mother was “hard”, and when her daughter passed her 11-plus on the second attempt she said she couldn’t go to the grammar school anyway because she had already bought the uniform for the other school. As Margaret says to Eileen now, “Your mum told you you were loved and you had to be adopted. My mum never said that. I remember waking up when I was eight years old and thinking, somebody had me and they didn’t want me. It’s horrifying, really traumatic for an eight-year-old.”
Eileen agrees that she came out better when it came to love and affection. “My mother always said Ellen [the twins’ birth mother] was very good to give me to her. She always pointed that out, and they picked me because they wanted me. I was secure despite the fact that I had to go and live in this tatty bungalow.”
Another difference in how their lives have progressed has been their choice of husbands. “You’ve been further afield than I have,” says Eileen to Margaret, turning to me and adding, “I think she’s more or less finished her bucket list. My husband won’t go. He’s not interested in travel. I’ve had to drag him out of the country.”
Identical twins show us that in the nature-versus-nurture debate, there is no winner. Both have their role to play in shaping who we are. But although we have reason to doubt that our genes determine our lives in some absolute way, this does not solve a bigger worry about whether or not we have free will.
Who we are appears to be a product of both nature and nurture, in whatever proportion they contribute, and nothing else. You are shaped by forces beyond yourself, and do not choose what you become. And so when you go on to make the choices in life that really matter, you do so on the basis of beliefs, values and dispositions that you did not choose.
Although this may appear troubling, it is hard to see how it could be any other way. For example, say you support a more redistributive tax system, because you think that is fair. Where did that sense of fairness come from? You may well have thought it through and come to a conclusion. But what did you bring to that process? A combination of abilities and dispositions that you were born with, and information and thinking skills that you acquired. In other words, a combination of hereditary factors and environment. There is no third place for anything else to come from. You are not responsible for how you emerged from the womb, nor for the world you found yourself in. Once you became old enough and sufficiently self-aware to think for yourself, the key determinants in your personality and outlook were already set. Yes, your views might be changed later in life by powerful experiences or persuasive books. But again, you do not choose for these things to change you. The very way we speak about such experiences suggests this. “This book changed my life,” we say, not “I changed my life with this book”, acknowledging that having read it, we did not choose to be different; we simply could never be the same again.
The literature on free will tends to focus on moments of choice: was I free at that point to do other than what I did? When we ask this, it often seems to us that only one option was viable. Sometimes this is because we think circumstances constrain us. But perhaps a more fundamental reason why at the moment of choice we cannot do otherwise is that we cannot be other than who we are. The nature of the chooser is the key determinant at the moment of choice: who we are comes first and what we do follows.
To be considered truly free, then, it would seem to be necessary for us to be in some sense responsible for being the people we are, and that responsibility needs to go “all the way down”: it has to be up to you and you alone what values and beliefs you hold dear and act upon. If we are not responsible for who we are, how can we be held responsible for what we do? But when we consider the dual roles of nature and nurture, the values we hold and beliefs we assert do not appear to be a matter of choice. We are formed by forces ultimately beyond our control. This thought, once made explicit, leads many to the conclusion that free will and responsibility are impossible. If you dig deep enough into what made us who we are, eventually you come across some key formative factors that we did not control. And if they are beyond our control, how can we be responsible for them?
On reflection, though, we ought to be more sanguine about not having complete control. The first step towards acceptance is to realise that it would be a very odd person whose actions did not in some sense flow from her values and beliefs. And yet the more strongly we hold these, the less we really feel free to choose other than the way we do. In 1521, the Reformation priest Martin Luther, for example, is reported to have told those who accused him of heresy at the Diet of Worms, “Here I stand. I can do no other.” This is not a denial of his freedom but an assertion of his freedom to act according to his values.
We cannot change our characters on a whim, and we would probably not want it any other way. A committed Christian does not want the freedom to wake up one day and become a Muslim. A family man does not want to find it as easy to run off with the au pair as to stick with his children and their mother. A fan of Shostakovich does not, usually at least, wish she could just decide to prefer Andrew Lloyd Webber. The critical point is that these key commitments don’t strike us primarily as choices. You don’t choose what you think is great, who you should love, or what is just. To think of these fundamental life commitments as choices is rather peculiar, perhaps a distortion created by the contemporary emphasis on choice as being at the heart of freedom.
What’s more, the idea that any kind of rational creature could choose its own basic dispositions and values is incoherent. For on what basis could such a choice be made? Without any values or dispositions, one would have no reason to prefer some over others. Imagine the anteroom in heaven, where people wait to be prepared for life on Earth. Some angel asks you, would you like to be a Republican or a Democrat? How could you answer if you did not already have some commitments and values that would tip the balance either way? It would be impossible.
Throughout human history, people have had no problem with the idea that their basic personality types were there from birth. The idea of taking after your parents is an almost universal cultural constant. Discovering just how much nature and nurture contribute to who we are is interesting, but doesn’t change the fact that traits are not chosen, and that no one ever thought they were.
Accepting this is ultimately more honest and liberating than denying it. Recognising how much our beliefs and commitments are shaped by factors beyond our control actually helps us to gain more control of them. It allows us to question our sense that something is obviously true by provoking us to ask whether it would appear so obvious if our upbringing or character had been different. It is only by recognising how much is not in our power that we can seize control of that which is. Perhaps most importantly, accepting how much belief is the product of an unchosen past should help us to be less dogmatic and more understanding of others. It doesn’t mean anything goes, of course, or that no view is right or wrong. But it does mean that no one is able to be perfectly objective, and so we should humbly accept that although objective truth is worth striving for, none of us could claim to have fully attained it.
Some may not be convinced yet that we should be so relaxed about our debt to nature and nurture. Unless we are fully responsible, it might seem unjust to blame people for their actions. If this seems persuasive, it is only because it rests on the false assumption that the only possible form of real responsibility is ultimate responsibility: that everything about who you are, what you believe and how you act is the result of your free choices alone. But our everyday notion of responsibility certainly does not and could not entail being ultimately responsible in this way. This is most evident in cases of negligence. Imagine you postpone maintaining a roof properly and it collapses during an exceptionally fierce storm, killing or injuring people below. The roof would not have collapsed if there had not been a storm, and the weather is clearly not in your control. But that does not mean you should not be held responsible for failing to maintain the building properly.
If the only real responsibility were ultimate responsibility, then there could never be any responsibility at all, because everything that happens involves factors both within and outside of our control. As the philosopher John Martin Fischer succinctly and accurately puts it, “Total control is a total fantasy – metaphysical megalomania.”
Many arguments that purport to debunk free will are powerful only if you buy into the premise that real responsibility is ultimate responsibility. Almost all those who deny free will define responsibility as though it must be total and absolute, or it is nothing at all. The Dutch neuroscientist Dick Swaab, who calls free will “an illusion”, does so by endorsing the definition of free will by Joseph L Price (a scientist, not a philosopher) as “the ability to choose to act or refrain from action without extrinsic or intrinsic constraints”. No wonder he is forced to conclude that, “Our current knowledge of neurobiology makes it clear that there is no such thing as absolute freedom.” Similarly, he claims that the existence of unconscious decision-making in the brain leaves “no room for a purely conscious, free will”. That’s true. The only question is why one would believe such absolute or pure freedom is possible or necessary.
The answer would appear to be to justify eternal damnation. As Augustine put it in the fourth century, “The very fact that anyone who uses free will to sin is divinely punished shows that free will was given to enable human beings to live rightly, for such punishment would be unjust if free will had been given both for living rightly and for sinning.” If the buck doesn’t stop with us, then it can only stop with the one who created us, making God ultimately responsible for our wickedness. Hence, as Erasmus put it, free will is theologically necessary “to allow the ungodly, who have deliberately fallen short of the grace of God, to be deservedly condemned; to clear God of the false accusation of cruelty and injustice; to free us from despair, protect us from complacency, and spur us on to moral endeavour.”
The ultimate punishment requires an ultimate responsibility which cannot exist. That is why we should not be worried to discover that factors outside our control, such as our genetic makeup, are critical to making us the people we have become. The only forms of freedom and responsibility that are both possible and worth having are those that are partial, not absolute. There is nothing science tells us that rules out this kind of free will. We know people are responsive to reasons. We know we have varying capacities of self-control which can be strengthened or weakened. We know there is a difference between doing something under coercion or because you decide yourself you want to. Real free will, not a philosopher’s fantasy, requires no more than these kinds of abilities to direct our own actions. It does not require the impossible feat of having written our own genetic code before we were even born.
If we become accustomed to thinking of freedom as completely unfettered, anything more limited will at first sight look like an emaciated form of liberty. You might even dismiss it as mere wiggle room: the ability to make limited choices within a framework of great restraint. But that would be a mistake. Unfettered freedom is not only an illusion; it makes no sense. It would not be desirable even if we could have it. Quite simply, the commonplace idea of free will we must ditch was always wrong. Good riddance to it.
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