Denis Farmer was filming storm clouds as they churned over his New Brunswick, Canada, home when, suddenly, the profile of a man appeared to emerge from the vapor. He recorded the event and, more than 3.5 million YouTube hits later, people are still debating whether the looming figure was a divine presence or just an illusion.

Science’s take? A psychological phenomenon called apophenia—which makes us prone to recognizing patterns—is to blame. More than anything, we’re hardwired to recognize faces, which is why we see deities in grilled cheese and Abraham Lincoln side-saddling a show pony in passing clouds. Once believed to be a sign of psychosis, this kind of apophenia is actually a handy evolutionary tool, since our survival depends on recognizing other members of our species, and our family, from a very young age.