There was once a wise Jew, who said that everything boils down to you have in your head.

His name was Moses

After him came a second wise Jew, who said that everything boils down to what you have in your heart.

His name was Jesus

After him came a third wise Jew, who said that everything boils down to what you have in the stomach.

His name was Marx

After him came a fourth wise Jew who said that everything boils down to what you have between the legs.

His name was Freud

And finally came the wisest of them all. His name was Einstein and he said that everything is relative.