Which One is Darker?

via 1000notes:

Which gray box is darker?
Maybe you think that it’s the top one, but you’re wrong. They have the same color. Try covering the line between them. You’ll see.

(Nat-Geo)

I bet your finger is on the monitor right now! :p
A fun TV show from National Geographic, Test Your Brain. (; I got pretty amazing and interesting stuffs from here hhas