Einstein, Casals, Picasso, and George W. Bush die and go to heaven. St. Peter is waiting for them, and requests identification. Einstein, who is first in line, says ""I don't have any ID, but I can explain the equivalence of matter and energy."" He is given a blackboard and proceeds to give an eloquent explanation of one of his most famous theories. ""Only Einstein himself could explain this so well,"" says St. Peter. ""Step right in, professor. Next?"" Then Casals, who is next in line, says ""Iβ¦