If you’ve ever touched someone’s hand or arm and thought “how is your skin so soft?!” you're not alone. But drop that lotion: According to a new study by researchers from University College London, the softness of other people's skin is often an illusion. 

In the study, which appears in Current Biologythe researchers found that people tend to judge the skin of others as being softer and smoother than their own. In a set of six different experiments, they tested 133 people to see if they could really tell whose skin was objectively softer. 

People overwhelmingly thought their skin was not as soft as their partner’s, even when there were no observable differences. However, they only felt this way when stroking forearms, where hair follicles help transmit pleasurable sensations to the brain of the person being touched. The same results did not hold for touching the palm, an area that people do not particularly enjoy having stroked. The illusion was more powerful during slow strokes than fast, which people on the receiving end tend to prefer, too. These results indicate that thinking someone’s skin is soft might help guide you to touch them in ways that are pleasurable.

The researchers postulate that this system might help cement social bonds between friends and family by making sure people enjoy touching each other (because nothing brings people together like petting each other). It’s possible that this illusion might be a little different when touching a friend versus a stranger, but that’s a topic for another study.