The Fool and the Wise Man
A fool and a wise man lived on a mountain. They found that they both had a hunger for clams.
The fool took his tools and went all over that mountain. Wherever he found sand, he dug. He found no clams, and came home very disappointed.
The wise man took his tools and walked to the seashore. There, he dug for clams; and he found all he could want. He came home very pleased.
It is not enough that you knock upon the door. You also must know where the door is so that you can knock upon it.