The science of soulmates: Is there someone out there exactly right for you?
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On Valentine's Day, many are tempted to believe that somewhere exists "The One": a soulmate, a perfect match, the person destined to be their partner.
Throughout history, humans have been captivated by the notion that love is not random. In ancient Greece, Plato imagined that humans were once whole beings with four arms, four legs, and two faces, so radiant that Zeus split them in two; since then, each half has wandered the earth searching for its missing counterpart. This myth provides the modern concept of the soulmate with poetic origins and the promise that somewhere, someone will finally make us feel complete.
In the Middle Ages, troubadours and Arthurian legends transformed that longing into "courtly love," a passionate, often forbidden devotion exemplified by Lancelot's love for Guinevere, where knights demonstrated their worth through self-sacrifice for a beloved they might never openly declare.
By the Renaissance, writers like Shakespeare spoke of "star-crossed lovers," couples bound by an overwhelming connection yet separated by family, fortune, or fate, as if the universe itself scripted their love story while denying them a happy ending.
In more recent times, Hollywood and romance novels have popularized fairy tale love stories.
But what does contemporary science reveal about soulmates? Is there truly a special someone out there for each of us?
How we fall for 'The One'
Viren Swami, Professor of Social Psychology at Anglia Ruskin University (ARU) in Cambridge, traces our current European understanding of romantic love back to medieval Europe and the tales of Camelot, Lancelot, Guinevere, and the chivalry of the knights of the round table that spread across the continent.
"These stories first pushed the idea that you should choose one other individual as your companion and that companion is for life," he says.
"Before that, in much of Europe, you could love as many people as you like, and love was fluid, and it was often not about sex."
As industrialization uprooted people from agricultural communities, disrupting familiar attachments, individuals became "alienated," he explains. "They start looking for one other individual to save them, to save them from the wretchedness of their lives."
Today's dating apps transform this narrative into an algorithm, which Swami terms "relation-shopping." The search for a soulmate becomes the opposite of what people seek: "For many people, that's a really soulless experience. You're shopping for a partner… going through possibly dozens of people on the dating app until you get to a point where you go… I need to stop," he says.
Jason Carroll, Professor of Marriage and Family Studies at Brigham Young University in Provo, Utah, empathizes with the longing for "The One."
"We are attachment-based creatures," he says. "We desire that bond." However, in his lectures, he advises students to let go of the idea of a soulmate without abandoning their desire for The One.
This may seem contradictory, but for Carroll, it distinguishes destiny from effort.
"A soulmate is just simply found. It's already pre‑made. But a one and only is something two people carve out together over years of adapting, apologising, and occasionally gritting their teeth," he explains.
Soulmate trap
Carroll's perspective is based on decades of research, compiled in his report, The Soulmate Trap, which differentiates between "destiny beliefs"—the idea that the right relationship should feel effortless—and "growth beliefs," which emphasize what partners can do to sustain their relationship.
In a well-known series of studies from the late 1990s and early 2000s led by Professor C. Raymond Knee at the University of Houston, researchers found that individuals who believed relationships were "meant to be" were more likely to question their commitment after conflict. Conversely, those with growth-oriented views tended to remain committed even on days of disagreement.
Carroll argues that those with growth-based beliefs still seek something special but anticipate challenges along the way.
"They ask… what can they do to make their relationship better, have improvement and have growth?"
He views the soulmate belief as a trap—not the romance itself, but the expectation that love should never be difficult. The most "soulful" aspect of a long-term relationship, he says, is not a dramatic moment but having "front-row seats not only for each other's strengths, but... [their] challenges and weaknesses."
"That's a pretty sacred space," he says. "We only know those things because they've let us be there."
For Carroll, treating love as fate reduces willingness to engage in the unglamorous work that sustains love. The soulmate trap makes it harder when a relationship encounters its first serious difficulty.
"The first time there's any type of struggle, the immediate thought is, 'well, I thought you were my soulmate. But maybe you're not, because soulmates aren't supposed to deal with things'," he says. "But if relationships are going to go long term, it's never just going to be a downhill run."
Spark or trauma?
Vicki Pavitt, a London-based love coach, often assists people who believed they had found their soulmate, only to discover that the relationship involved emotional manipulation, inconsistency, and persistent anxiety.
"When there is a lot of chemistry and the spark, I think that can sometimes be about opening old unhealthy patterns, like old wounds," she explains.
She continues,
"A person who is inconsistent or plays a bit hot and cold can make you feel 'I can't wait to see them again', but what's really happening is they're giving you so much anxiety and that it has you wanting more."
Pavitt suggests that what we interpret as destiny may be a response from our nervous system recognizing past trauma and attempting to resolve it, a pattern therapists refer to as a trauma bond.
This bond can resemble love and causes individuals to be drawn into unhealthy dynamics because they are familiar, not because they represent the perfect match.
One frequently cited study by Canadian psychologists Donald Dutton and Susan Painter, published in 1993 while at the University of British Columbia, followed 75 women after leaving abusive partners.
The researchers measured the strength of the women's attachment to their ex-partners and compared it with the nature of their relationships.
They found the strongest bonds were not among women who were consistently abused, but among those whose partners alternated between charm and cruelty.
Dutton and Painter argue that this trauma bond explains why people feel magnetically drawn back to relationships that are objectively harmful—because the combination of danger and affection is familiar, not healthy.
Pavitt aims to clarify this distinction in her coaching:
"It's about discerning whether the chemistry you feel is showing me this person's compatible with me or if it is a familiar sense of anxiety.
In my language, I never talk about soulmates," she says. "I don't personally believe that there is one person for everybody... but I do believe that we become 'The One' for someone."
Real chemistry
If dismissing the existence of a soulmate seems unromantic, biological research points in a similar direction.
Hormonal contraceptives may subtly influence how partners feel about each other. Studies suggest that contraceptive pills, which stabilize the natural fluctuations of fertility, can reduce shifts in attraction typically observed across the menstrual cycle, potentially affecting initial mate choice.
One large study involving 365 heterosexual couples found that women's sexual satisfaction was higher when their current contraceptive status matched that at the time they chose their partner, indicating that changes in pill use can alter perceptions of a partner. Although these effects are small, they may help explain some couples' puzzling changes in chemistry over time.
If hormones and contraceptives can influence who feels like "The One," it becomes more difficult to argue for a single, preordained match—leading to insights from mathematics.
The one but not the only
Psychology and biology offer one perspective on "The One," but mathematics proposes another.
Dr. Greg Leo, an economist at Vanderbilt University in Nashville, Tennessee, developed a compatibility algorithm suggesting that individuals may have multiple "Ones."
In his paper Matching Soulmates published in the journal Public Economic Theory, he simulates a dating pool where thousands of digitally created daters rank each other. His algorithm identifies "first‑order soulmates": pairs who mutually choose each other in a stable matching. These pairs are removed, and the process repeats with the remaining participants, identifying second‑order soulmates, and so forth.
In his simulations, it was rare for someone to have their mutual first picks; however, many had second or third picks. In this model, a couple is considered happy if each is near the top of the other's list and neither can find someone they both prefer more.
Though based on computational modeling, this love algorithm suggests there are many viable partners, not just a single "One."
Sweat the small stuff
How can couples co-create their "Ones"?
Jacqui Gabb, Professor of Sociology and Intimacy at The Open University, explored this in her Enduring Love project, published in the journal Sociology in 2015.
The study surveyed approximately 5,000 people and followed 50 couples in detailed, sometimes intrusive ways, combining statistics with diaries, interviews, and "emotion maps" documenting home life.
When participants were asked what made them feel appreciated, it was not grand gestures like sunset proposals or surprise trips to Paris.
Instead, it was "surprise gifts, thoughtful gestures and the kindness of a cup of tea in bed." Warming the car on a cold morning, picking wildflowers and placing them in a vase, sharing a private smile at a party.
Quantitative data showed these "everyday attentive acts" were more powerful than grand romantic gestures.
In her survey, 22% of mothers and 20% of childless women ranked such small gestures among the top two factors that made them feel valued—more than big nights out or expensive presents.
Relationship satisfaction was less about money or romance and more about "intimate couple knowledge" expressed in daily life.
One young couple's diary from the project illustrates this. Sumaira describes her partner coming home, the dinner she prepared, the hug in the hallway, and the two of them eating together at the table.
"It's perfect," she writes. "Just us and food. What more could I want?"
Later, they share a spontaneous dance in the living room, a walk through tall grass where she fears the dark, and a photo her partner cherishes so much he makes it his phone background.
The story reads like a lovely everyday tale, not a fairy tale: no glass slippers, but wellies.
Yet Gabb notes that woven through the sweetness are financial worries, family obligations, and a history of depression that the couple are learning to manage together.
"The soulmate feeling here doesn't float above life; it is made, inch by inch, by life, in the way the pair meet those pressures," she says.
Valentine's Dinner
The science does not diminish romance; rather, it supports its growth in both good times and bad, according to Carroll.
"I'm pretty comfortable with the aspiration to be in a unique special relationship as long as we remember it needs to be created," he says.
Pavitt believes,
"it's fine, helpful, even to have faith that your person is out there, so long as you know there are many people that you could form a really great connection with and stop expecting anyone to be perfect."
Regarding soulmates, science reveals a paradox. Those who end up in relationships that feel uniquely "meant to be" are often the ones who stopped waiting for fate, turned toward the imperfect person before them, and effectively said: shall we make something of this?
Additional reporting by Florence Freeman
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