You think you can do anything, and then you slowly learn how wrong you are.

"Eating crow" is an old expression defined by the Urban Dictionary to mean "When you make a mistake and are forced to acknowledge it humbly".

"Geometry has two great treasures; one is the Theorem of Pythagoras; the other, the division of a line into extreme and mean ratio. The first we may compare to a measure of gold; the second we may name a precious jewel."