We all know the feeling: someone catches your eye, you get butterflies in your stomach and you can’t stop thinking about them. But why are we drawn to certain people and not others, and what exactly is it that makes us fancy them?

Well, it turns out that the rules of attraction aren't that straightforward. According to professor Claire Hart, who teaches a module on the psychology of attraction at University of Southampton, there are five main determinants of attraction: physical attractiveness, proximity, similarity, reciprocity and familiarity.

Here, we take a closer look at these factors to try and find out what makes us attracted to someone else.

Hey good looking

Naturally, physical appearance plays an important role in the initial stages of attraction. If you look like Brad Pitt or Scarlett Johansson, you’re more likely to have a host of admirers. And the reason is simple enough, says Claire – we like to look at things that are visually appealing. “Aesthetic appeal is desirable and leads to positive affect – it feels good to be around beautiful people.”

But it also has a lot to do with biology and evolution. Take symmetrical facial features for example, which is considered desirable because we’ve come to associate it with good health. “Preference for symmetry is a highly evolved trait in many different animals and is equated with a strong immune system and good genes,” explains Claire.

Interestingly, Claire adds that we often see attractive people as having a variety of other positive attributes (known as the ‘halo effect’). “We assume beautiful people have other favourable traits, including being kind, honest, intelligent, talented, socially competent and better adjusted.”

But that’s not to say physical attractiveness is important for everyone; personality also influences who we like. It differs between genders too, says Claire. “Evolutionary theory would argue that men care more about physical attraction and women care more about emotional ties, which stems back to our evolutionary past.”

Ham & High: Being exposed to someone repeatedly is enough to make you like themBeing exposed to someone repeatedly is enough to make you like them (Image: Milenko Bokan)

Fancy seeing you here

Ever felt attracted to someone but you can’t quite put your finger on why? Perhaps it’s a colleague who you once found irritating, or that person you keep seeing in your local shop. This can be explained by the basic principle of proximity – in other words, who is accessible. “Proximity is one of the most influential factors in narrowing our pool of potential partners,” says Claire. “This is a psychological phenomenon where being exposed to a person repeatedly is sufficient enough to produce liking for that person.”

But the increased use of dating apps (now even more popular thanks to social distancing) has skewed this phenomenon through what Claire describes as “choice overload”. That is, having multiple partners to choose from can alter our perception of who would be a good match in real life. “With more choice we’re more likely to prioritise different qualities when browsing than when conducting separate evaluations of potential partners,” says Claire, “and such attributes could be irrelevant to those that would make you happy once a relationship moves offline.

“Our type can change depending on who we are comparing others against, which suggests we don’t really have a type,” she adds.

Ham & High: Having multiple partners to choose from on dating apps can alter your perception of who would be a good match in real lifeHaving multiple partners to choose from on dating apps can alter your perception of who would be a good match in real life (Image: Getty)

Birds of a feather flock together

Yes, it might sound narcissistic, but we really are drawn to others who are similar to ourselves. “The more similar a prospective partner’s attitudes, beliefs, and values are, the more we tend to like them,” says Claire. “This also extends to demographic characteristics, levels of physical attractiveness, and non-verbal behaviours, such as mimicry.”

One of the reasons why similarity may influence attraction is that it provides a source of validation of our own beliefs and attitudes. This links to the reciprocity theory, in that there’s a greater chance that someone similar to you will like you back, which reduces the risk of rejection.

We also like things that are familiar, predictable and safe, says Claire. “The more similar you are the less conflict there will be, making spending time together easier and more rewarding. Relationships based on differences, rather than similarities can be very difficult to maintain – suitably matched couples function more smoothly.”

So, it would seem that there's a whole host of factors at play when it comes to the psychology of attraction, and it’s important to remember that it’s different for everyone. As Claire says: “Relationships vary – just because there's not an initial spark doesn’t mean that feelings won’t develop over time.” In other words, if you're pursuing someone romantically, it might be best not to overthink it.