When you look at Da Vinci's art, it's not hard to see why he's hailed as a genius. But he may have had a little trick up his sleeve that helped him see the world a little differently than most people, in the form of an eye disorder shared by Picasso, Rembrandt, and even Ryan Gosling. Charlie brings in a paper that tries to determine if Da Vinci had a condition known as strabismus. Read the paper and news articles here.