Optical illusions can make you go crazy. As hard as you try not to get “tricked” by them, it’s basically impossible, as it has to do with your brain. One of those optical illusions that has recently made the internet baffled is a picture of six girls sitting on a couch. However, there are only five pairs of legs. How does that work? Let’s find out!

Optical illusions always baffle me – and now, one of them is baffling the entire internet too. Per the Queensland Brain Institute, an optical illusion happens “when our brain and eyes try to speak to each other in simple language but the interpretation gets a bit mixed-up.”

It further read, “For example, it thinks our eyes told it something is moving, but that’s not what the eyes meant to say to the brain.(Our brains and eyes evolved to be quite sensitive about movement because in prehistoric times it was a big help if you could spot movement early and often. A slight rustle in the bushes could mean a predator was nearb,y and it was time to run away. Spotting movement early could save your life!)

On Reddit, one optical illusion has gone viral. The picture shows six girls sitting on a couch, but you can only see five pairs of legs. It appears as if one person is missing a pair of legs, and on the online forum, people have tried to find the solution.

Per The Tab, one person wrote, The second girl’s legs are behind the first girl’s legs,” meaning that the one girl sitting second from the left hides her legs behind the one sitting farthest to the left. You can’t see it – but that is what makes it a brain teaser.