Untitled (Portrait of a Man and a Woman) (1851), daguerreotype, United States. Courtesy the Art Institute of Chicago


Tainted love

Love is both a wonderful thing and a cunning evolutionary trick to control us. A dangerous cocktail in the wrong hands

by Anna Machin + BIO

Untitled (Portrait of a Man and a Woman) (1851), daguerreotype, United States. Courtesy the Art Institute of Chicago

We can all agree that, on balance, and taking everything into account, love is a wonderful thing. For many, it is the point of life. I have spent more than a decade researching the science behind human love and, rather than becoming immune to its charms, I am increasingly in awe of its complexity and its importance to us. It infiltrates every fibre of our being and every aspect of our daily lives. It is the most important factor in our mental and physical health, our longevity and our life satisfaction. And regardless of who the object of our love is – lover or friend, dog or god – these effects are largely underpinned, in the first instance, by the set of addictive neurochemicals supporting the bonds we create: oxytocin, dopamine, beta-endorphin and serotonin.

This suite of chemicals makes us feel euphoric and calm, they draw us towards those we love, and reward us for investing in our relationships, even when the going gets tough. Love feels wonderful but ultimately it is a form of biological bribery, a cunning evolutionary trick to make sure we cooperate and those all-important genes continue down the generations. The joy it brings is wonderful but is merely a side-effect. Its goal is to ensure our survival, and for this reason happiness is not always its end point. Alongside its joys, there exists a dark side.

Love is ultimately about control. It’s about using chemical bribery to make sure we stick around, cooperate and invest in each other, and particularly in the survival-critical relationships we have with our lovers, children and close friends. This is an evolutionary control of which we are hardly aware, and it brings many positive benefits.

But the addictive nature of these chemicals, and our visceral need for them, means that love also has a dark side. It can be used as a tool of exploitation, manipulation and abuse. Indeed, in part what may separate human love from the love experienced by other animals is that we can use love to manipulate and control others. Our desire to believe in the fairy tale means we rarely acknowledge the undercurrents but, as a scholar of love, I would be negligent if I did not consider it. Arguably our greatest and most intense life experience can be used against us, sometimes leading us to continue relationships with negative consequences in direct opposition to our survival.

We are all experts in love. The science I write about is always grounded in the lived experience of my subjects whose thoughts I collect as keenly as their empirical data. It might be the voice of the new father as he describes holding his firstborn, or the Catholic nun explaining how she works to maintain her relationship with God, or the aromantic detailing what it’s like living in a world apparently obsessed with the romantic love that they do not feel. I begin every interview in the same way, by asking what they think love is. Their answers are often surprising, always illuminating and invariably positive, and remind me that not all the answers to what love is can be found on the scanner screen or in the lab. But I will also ask them to consider whether love can ever be negative. The vast majority say no for, if love has a darker side, it is not love, and this is an interesting point to contemplate. But if they do acknowledge the possibility of love having a less sunny side, their go-to example is jealousy.

Jealousy is an emotion and, as with all emotions, it evolved to protect us, to alert us to a potential benefit or threat. It works its magic at three levels: the emotional, the cognitive and the behavioural. Physiology also throws its hat into the ring making you feel nauseous, faint or flushed. When we feel jealousy, it is generally urging us to do one of three things: to cut off the rival, to prevent our partner’s defection by redoubling our efforts, or to cut our losses and leave the relationship. All have evolved to make sure we balance the costs and benefits of the relationship. Investing time, energy and reproductive effort in the wrong partner is seriously damaging to your reproductive legacy and chances of survival. But what do we perceive to be a jealousy-inducing threat? The answer very much depends on your gender.

Men and women experience jealousy with the same intensity. However, there is a stark difference when it comes to what causes each to be jealous. One of the pioneers of human mating research is the American evolutionary psychologist David Buss and, in his book The Evolution of Desire (1994), he details numerous experiments that have highlighted this gender difference. In one study, in which subjects were asked to read different scenarios detailing incidences of sexual and emotional infidelity, 83 per cent of women found the emotional scenario the most jealousy-inducing, whereas only 40 per cent of men found this to be of concern. In contrast, 60 per cent of men found sexual infidelity difficult to deal with, compared with a significantly smaller percentage of women: 17 per cent.

Men also feel a much more extreme physiological response to sexual infidelity than women do. Hooking them up to monitors that measure skin conductance, muscle contraction and heartrate shows that men experience significant increases in heartrate, sweating and frowning when confronted with sexual infidelity, but the monitor readouts hardly flicker if their partner has become emotionally involved with a rival.

The reason for this difference sits with the different resources that men and women bring to the mating game. Broadly, men bring their resources and protection; women bring their womb. If a woman is sexually unfaithful and becomes pregnant with another man’s child, she has withdrawn the opportunity from her partner to father a child with her for at least nine months. Hence, he is the most concerned about sexual infidelity. In contrast, women are more concerned about emotional infidelity because this suggests that, if their partner does make a rival pregnant and becomes emotionally involved with her, his partner risks having to share his protection and resources with another, meaning that her children receive less of the pie.

To understand someone’s emotional needs means you can use that intelligence to control them

Jealousy is an evolved response to threats to our reproductive success and survival – of self, children and genes. In many cases, it is of positive benefit to those who experience it as it shines a light on the threat and enables us to decide what is best. But in some cases, jealousy gets out of hand.

Emotional intelligence sits at the core of healthy relationships. To truly deliver the benefits of the relationship to our partner, we must understand and meet their emotional needs as they must understand and meet ours. But, as with love, this skill has a darker side because to understand someone’s emotional needs presents the possibility that you can use that intelligence to control them. While we may all admit to using this skill for the wrong reasons every now and again – perhaps to get that sofa we desire or the holiday destination we prefer – for some, it is their go-to mechanism where relationships are concerned.

The most adept proponents of this skill are those who possess the Dark Triad of personality traits: Machiavellianism, psychopathy and narcissism. The first relies on using emotional intelligence to manipulate others, the second to toy with other’s feelings, and the third to denigrate others with the aim of glorifying oneself. For these people, characterised by exploitative, manipulative and callous personalities, emotional intelligence is the route to a set of mate-retention behaviours that certainly meet their goals but are less than beneficial to those whom they profess to love. Indeed, research has shown that a relationship with such a person leaves you open to a significantly greater risk that your love will be returned with abuse.

In 2018, the psychologist Razieh Chegeni and her team set out to explore whether a link existed between the Dark Triad and relationship abuse. Participants were identified as having the Dark Triad personality by expressing their degree of agreement with statements such as ‘I tend to want others to admire me’ (narcissism), ‘I tend to be unconcerned with the morality of my actions’ (psychopathy) and ‘I tend to exploit others to my own end’ (Machiavellianism). They then had to indicate to what extent they used a range of mate-retention behaviours, including ‘snooped through my partner’s personal belongings’, ‘talked to another man/woman at a party to make my partner jealous’, ‘bought my partner an expensive gift’ and ‘slapped a man who made a pass at my partner’.

The results were clear. Having a Dark Triad personality, whether you were a man or a woman, significantly increased the likelihood that ‘cost-inflicting mate-retention behaviours’ were your go-to mechanism when trying to retain your partner. These are behaviours that level an emotional, physical, practical and/or psychological cost on the partner such as physical or emotional abuse, coercive control or controlling access to food or money. Interestingly, however, these individuals did not employ this tactic all the time. There was nuance in their behaviour. Costly behaviours were peppered with rare incidences of gift giving or caretaking, so-called beneficial mate-retention behaviours. Why? Because the unpredictability of their behaviour caused psychological destabilisation in their partner and enabled them to assert further control through a practice we now identify as gaslighting.

The question remains – if these people are so destructive, why does their personality type persist in our population? Because, while their behaviour may harm those who are unfortunate enough to be close to them, they themselves must gain some survival advantage, which means that their traits persist in the population. It is true that no trait can be said to be 100 per cent beneficial, and here is a perfect example of where evolution is truly working at cross purposes.

Not all Dark Triad personalities are abusers but the presence of abuse within our closest relationships is a very real phenomenon, the understanding of which continues to evolve and grow. Whereas we might have once imagined an abuser as someone who controlled their partner with their fists, we are now aware that abuse comes in many guises including emotional, psychological, reproductive and financial.

The US Centers for Disease Control and Prevention (CDC) questioned both men and women in the United States about the incidences of domestic violence they had experienced in their lifetime. Looking at severe physical abuse alone – which means being punched, slammed, kicked, burned, choked, beaten or attacked with a weapon – one in five women and one in seven men reported at least one incidence in their lifetime. If we consider emotional abuse, then the statistics for men and women are closer – more than 43 million women and 38 million men have experienced psychological aggression by an intimate partner in their lifetime.

It is hard to imagine that, having experienced such a litany of abuse, anyone could believe that love remained within their relationship. But here the power of the lived experience, of allowing everyone to have their ideas about love becomes clearer. Because, while we have many scientific tools to explore love objectively, at the end of the day, there is always an element of our experience of love that is subjective, that another cannot touch. This is no more powerfully evidenced than by the testimony of those who have experienced intimate partner violence. In 2013, three mental health nurses, led by Marilyn Smith in West Virginia, explored what love meant to 19 women who were experiencing, or had experienced, intimate partner violence. For them, this kind of abuse included, but was not limited to, ‘slapping, intimidation, shaming, forced intercourse, isolation, monitoring behaviours, restricting access to healthcare, opposing or interfering with school or employment, and making decisions concerning contraception, pregnancy, and elective abortion’.

Our cultural ideas of romantic love have a role to play in trapping women in abusive relationships

It was clear from the transcripts that all the women knew what love wasn’t: being hurt and fearful, being controlled and having a lack of trust and a lack of support or concern for their welfare. And it was clear that they all knew what love should be: built on a foundation of respect and understanding, of support and encouragement, of commitment, loyalty and trust. But despite this clear understanding of the stark difference between the ideal and their reality, many of these women still believed that love existed within their relationship. Some hoped the power of their love would change the behaviour of their partner, others said their sense of attachment made them stay. Some feared losing love, however flawed; and, if they left, might they not land in a relationship where their treatment was even worse? A lot of the time, cultural messaging had reinforced strongly held beliefs about the supremacy of the nuclear family, making victims reluctant to leave in case they ultimately harmed their children’s life chances. While it can be hard to understand these arguments – surely a non-nuclear setup is preferable to the harm inflicted on a child by the observation of intimate partner abuse – I strongly believe that this population has as much right to their definition and experience of love as any of us.

In fact, the cultural messages we hear about romantic love – from the media, religion, parents and family – not only potentially trap us in ‘ideal’ family units: they may also play a role in our susceptibility to experiencing intimate partner abuse. This view of reproductive love, once confined to Western culture, is now the predominant narrative globally. From a young age, we speak of ‘the one’, we consume stories of young people finding love against all the odds, of sacrifice, of being consumed. It is arguable that these narratives are unhelpful generally as the reality, while wonderful, is considerably more complex, involving light and shade. But research has shown that these stories may have more significant consequences when we consider their role in intimate partner abuse.

South Africa has one of the highest rates of partner abuse against women in the world. In their 2017 paper, Shakila Singh and Thembeka Myende explored the role of resilience in female students at risk of abuse, which is prevalent at a high rate on South African university campuses. Their paper ranges widely over the role of resilience in resisting and surviving partner abuse, but what is of interest to me is the 15 women’s ideas about how our cultural ideas of romantic love have a role to play in trapping women in abusive relationships. These women’s arguments are powerful and made me rethink the fairy-tale. Singh and Myende point to the romantic idea that love overcomes all obstacles and must be maintained at all costs, even when abuse makes these costs life-threateningly high. Or the idea that love is about losing control, being swept off your feet, having no say in who you fall for, even if they turn out to be an abuser. Or that lovers protect each other, fight for each other to the end, even if the person who is being protected, usually from the authorities, is violent or coercive. Or the belief that love is blind and we are incapable of seeing our partner’s faults, despite them often being glaringly obvious to anyone outside the relationship.

It is these cultural ideas about romantic love, the women argue, that lead to the erosion of a woman’s power to leave or entirely avoid an abusive partner. Add these ideas to the powerful physiological and psychological need we have for love, and you leave an open goal for the abuser.

Love is the focus of so much science, philosophy and literary rumination because we struggle to define it, to predict its next move. Thanks to our biology and the reproductive mandate of evolution, love has long controlled us. But what if we could control love?

What if a magic potion existed that could induce us, or another, to fall in love or even wipe away the memories of a failed relationship? It is a quest as ancient as the first writings 5,000 years ago and the focus of many literary endeavours, including Shakespeare’s A Midsummer Night’s Dream – who can forget Titania’s love for the ass-headed Bottom – and Wagner’s opera Tristan and Isolde. Even in a world where science has largely usurped magic, type ‘love potions’ into Google and the first two questions are: ‘How do you make a love potion?’ and ‘Do love potions actually work?’

But today we know enough about the chemistry of love for the elixir to be within our grasp. And we don’t have to look very far for our first candidate: synthetic oxytocin, used right now as an induction drug in labour. We know from extensive research in social neuroscience that artificial oxytocin also increases prosociality, trust and cooperation. Squirt it up the nose of new parents and it increases positive parenting behaviours. Oxytocin, as released by the brain when we are attracted to someone, is vital for the first stages of love because it quiets the fear centre of your brain and lowers your inhibitions to forming new relationships. Would a squirt up the nose do the same before you head out on a Saturday night?

The other possibility is MDMA or ecstasy, which mimics the neurochemical of long-term love, beta-endorphin. Recreational users of ecstasy report that it makes them feel boundless love for their fellow clubbers and increases their empathy. Researchers in the US have reported encouraging results when MDMA was used in marriage therapy to increase empathy, allowing participants to gain further insight into each other’s needs and find common ground.

Love drugs could end up being yet another form of abuse

Both of these sound like promising candidates but there are still issues to iron out and ethical discussions to have. How effective they are is highly context dependent. Based on their genetics, some people do exactly what is predicted of them. Boundaries are lowered and love sensations abound. But for a significant minority, particularly when it comes to oxytocin, people do exactly the opposite of what we would expect. For some, a dose of oxytocin, while increasing bonds with those they perceive to be in their in-group, increases feelings of ethnocentrism – racism – toward the out-group.

MDMA has other issues. For some people, it simply does not work. But the bigger problem is that the effects endure only while usage continues; anecdotal evidence suggests that, if you stop, the feelings of love and empathy disappear. This raises questions of practicality and ethical issues surrounding power imbalance. If you commenced a relationship while taking MDMA, would you have to continue? What if you were in a relationship with someone who had taken MDMA and you didn’t know? What would happen if they stopped? And could someone be induced to take MDMA against their will?

The ethical conversation around love drugs is complex. On one side are those who argue that taking a love drug is no more controversial than an antidepressant. Both alter your brain chemistry and, given the strong relationship between love and good mental and physical health, surely it is important that we use all the tools at our disposal to help people succeed? But maybe an anecdote from the book Love Is the Drug (2020) by Brian Earp and Julian Savulescu will give you pause. They describe SSRI prescriptions used to suppress the sexual urges of young male yeshiva students, to ensure that they comply with Jewish orthodox religious law – no sex before marriage, and definitely no homosexuality.

Could such drugs gain wider traction in repressive regimes as a weapon against what some perceive to be immoral forms of love? Remember that 71 countries still deem homosexuality to be illegal. It is not a massive leap of imagination to envisage the use of SSRIs to ‘cure’ people of this ‘affliction’. We only have to look at the continued existence of conversion therapy to see that this is a distinct possibility. Love drugs could end up being yet another form of abuse over which the individual has very little control.

Evolution saw fit to give us love to ensure we would continue to form and maintain the cooperative relationships that are our route to personal and, most crucially, genetic survival. It can be the source of euphoric happiness, calm contentment and much-needed security, but this is not its point. Love is merely the sweet treat handed to you by your babysitter to make sure the goal is achieved. Combine the ultimate evolutionary aim of love with our visceral need for it and the quick intelligence of our brains, and you have the recipe for a darker side to emerge. Some of this darker side is adaptive but, for those who experience it, it rarely ends well. At the very least there is pain – physical, psychological, financial – and, at the most, there is death, and the grief of those we leave behind.

Maybe it is time to rewrite the stories we tell ourselves about love because the danger on the horizon is not the dragon that needs to be slain by the knight to save the beautiful princess but the presence of some who mean to use its powers for their gain and our considerable loss. Like all of us, love is a complex beast: only by embracing it in its entirety do we truly understand it, and ourselves. And this means understanding its evolutionary story, the good and the bad.