This is one of the most impressive things I have ever seen. I am absolutely blown away. Abbie used to babysit for a kid who could do the date thing in his head, but he hadn’t gotten to powers yet. Once I gave him a quick overview of squares and quizzed him a bit, and five minutes later he’d moved on to cubes. Quiz over, since I didn’t have a calculator on me. Plus he was busy trying to figure out how the remote worked.

He was 5.

By the way, if you’re not watching these TED talks regularly, you should be. Subscribe to the podcast version here.