Human World

Be my Valentine? Why we fall in love

Echocardiogram graph in red with one spike being a heart.
This picture isn’t a valentine but sometimes love makes your heart leap! Image via The Irish Times.

When I was young, it seemed as if I fell in love a lot. Looking back now, more than half a century from my first crush, I remember the dizzying feeling of new intimacies, emotional boundaries crashing down, two hearts thumping, two hands touching, the whole huge magical adrenaline rush of it. And if the prince turned out to be a toad, or geography nixed the relationship, well … I turned my thoughts to working hard and living a happy life. On this Valentine’s Day 2022, I want to share with you what the world of science suggests, from the perspective of one who has loved long and a lot, about the mystery we call love.

Reasons we fall in love

Science explains love in many ways. From various scientists and scientific studies, here are some reasons why we love.

1. Because we all want to “expand beyond ourselves.” Pyschologist Arthur Aron at Stony Brook University has conducted studies suggesting that a primary motive for us as humans is to “expand the self and to increase our abilities and our effectiveness.” He told

Usually, we fall in love with a person that we find attractive and appropriate for us, but also someone who demonstrates that they are attracted to us. This creates a situation where a great opportunity is open to us for self-expansion. The fact that they are attracted to us offers a significant opportunity – when we perceive this, we feel a surge of exhilaration!

Valentine: Young man and woman gazing into each other's eyes across a table with coffee cups on it.

2. Good eye contact. Arthur Aron again (see #1). He conducted a study that encouraged strangers of the opposite sex to discuss intimate details about themselves for 90 minutes. At the end of that time, each couple stared into each other’s eyes for four minutes in silence. The results? Many of the couples said they felt a deep attraction to each other, even though they’d never met before. Two of the couples ended up married.

3. Because of inner and outer synchronicity. We fall in love, says psychologist Mark B. Kristal of the University at Buffalo College of Arts and Sciences, when processes in our bodies align with appropriate triggers from the outside world. He speaks of “visual, regular olfactory, auditory and tactile cues” happening in “the proper time, order and place.” He told

There are several types of chemistry required in romantic relationships. It seems like a variety of different neurochemical processes and external stimuli have to click in the right complex and the right sequence for someone to fall in love

Two people with heads wrapped entirely in cloth kissing through it.
The Lovers by Rene Magritte, 1928.

4. Because we like the way they smell. Many studies have shown that smell plays a role in love. Plus we’re not just talking about the ordinary smell of your lover’s dirty T-shirts (dirty T-shirts, by the way, have been the stock-in-trade of smell studies), but also those other, perhaps odorless, signals that enter the brain through the olfactory system. That’s right, pheromones. Volumes have been written on the subject of smell and pheromones in attraction, love and marriage, and don’t we all know it’s true?

5. Because we like the way they kiss. Kissing has an element of smell to it, obviously, but kissing all by itself can determine if the relationship holds promise. Sheril Kirshenbaum, author of the book The Science of Kissing, told EarthSky that a kiss, and especially a first kiss, plays a big role in determining the future of a relationship, according to scientific studies. She said:

Fifty-nine percent of men and 66 percent of women say they have ended a budding relationship because a kiss didn’t go well. It’s your body’s way of saying, look elsewhere.

Bare-chested young man kissing fully dressed young woman.
Via ValetheKid.

6. Because of our hormones. You know how your heart pounds and your mouth goes dry when your new lover rings the doorbell? It’s basically a stress response. Romantic, eh? Adrenaline, dopamine and serotonin all come into play in love’s early stages. Love-struck couples also have high levels of the neurotransmitter dopamine, which stimulates an intense rush of pleasure, essentially the same effect on the brain as taking cocaine (see #9, below). Want to learn more about hormones in love? Try this post from Scientific American: Your brain in love.

7. Because sex is good for us. Sex relieves stress, boosts immunity, burns calories, boosts heart health, improves intimacy … and so much more. You can read more about the health benefits of sex in this post from WebMD.

8. To make and raise babies, together. Martie Haselton, a psychologist at UCLA, believes love is a “commitment device,” a mechanism that encourages two humans to form a lasting bond to ensure the “long-term health of children.” Haselton and her colleagues conducted experiments, asking people to think about how much they love their partners while suppressing thoughts of other attractive people. They then have the same people think about how much they sexually desire their partners while suppressing thoughts about others. It turns out that love does a much better job of pushing out potential rivals than sex does. This is what you’d expect, Haselton says, if love was a drive to form a long-term commitment. She said:

Natural selection has built love to make us feel romantic.

9. Because love is a drug. Neuroscientist Thomas Insel and colleagues at Emory University in Atlanta conducted studies showing that that monogamous pair bonding among prairie voles (small rodents that mate for life) affects the same brain reward circuits that are responsible for addiction to cocaine and heroin.

They say their conclusions are probably true for humans, too. As Robert Palmer said, you’re gonna have to face it:

10. Because we are created for love. Who said that? I did.

Okay, so now we know some of what the world of science has to offer on the subject of falling in love. Meanwhile, what’s the best way to stay in love? Psychologist Arthur Aron says the best predictor for lasting long-term relationships is kindness.

Love, sweet love

And lest you take any of this too seriously, remember …

Although I speak in tongues
Of men and angels
I’m just sounding brass
And tinkling cymbals without love.
– 1 Corinthians 13:1 (translation from Joni Mitchell)

In other words, despite all that science has to offer, there’s something about love, falling in love, being in love, showing love, maintaining lifelong love – whether that’s between romantic partners, parents and children, friends or people in the world at large – that transcends all our definitions and attempts to understand. True, scientific studies have shown neurochemical, psychological, olfactory, evolutionary and psychological reasons for love. But, in the end, we love who we love, and the act of loving makes us who we are.

Bottom line: Thoughts from the world of science on why we fall in love. Happy Valentine’s Day 2022!

February 14, 2022
Human World

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