Ok, I recieved this optical illusion recently, and thought to my self: “Funny! It appears that the boy is juggling, while in fact the ball is standing still on the grass in the background”. Wrong! It is the other way arround actually! In the first case, the ball would have to be much bigger than actual to appear normal-sized (because of the distance). On the other hand, if the boy is juggling, it would have to be much smaller, since it looks really small. Then it hit me! The boy you see is juggling a mini soccer ball! You might have seen those during World Cup in Germany! Did you like this illusion? I did for sure! It belongs to Relative Sizes Category.