There might be piles of op-eds bemoaning the dwindling attention spans of the digital age, but magicians know better. They know that humans’ ability to see and observe has always been a fragile thing, a thing that’s easy to manipulate or to fail completely. Magic historian David Britland delves into some of the more incredible examples of this phenomenon in his One Weird Trick blog.

For instance, he’s got the story of Harry Blackstone, a magician who was so good at misdirection he could distract an audience while a donkey was moved into position to be the trick’s big reveal. Nobody would see the donkey, even though the animal was in plain view on the stage, until Blackstone wanted them to.

On the more academic side, he also shares a research experiment by Daniel Simons and Christopher Chabris of Harvard that put humans’ selective blindness to the test in a similar fashion. Instead of a donkey, the professors had people watch a group of people passing a ball so intently that many of the participants completely ignored the cameo by someone in a gorilla suit.

Check out the full post for more examples of selective inattention in action. Or if you still need more on the science of misdirection, you can read about it in the Quarterly Journal of Experimental Psychology or in The Guardian. Or just watch your favorite magician doing their thing.