Like most children, one of my early exposures to the idea of purpose came from the story of Alice in Wonderland written by Lewis Carroll. The story is about a girl named Alice who falls down a rabbit hole into a fantasy world populated by a collection of creatures.
When Alice comes to a place where the road splits and forces her to decide on which direction she take she encounters a Cheshire Cat sitting in a tree. Alice ask the Cheshire Cat for assistance in making her difficult choice.
Alice ask, “Would you tell me, please, which way I ought to go from here?”
“That depends a good deal on where you want to get to,” said the Cat.
“I don’t much care where–” said Alice.
“Then it doesn’t matter which way you go,” said the Cat.
“–so long as I get SOMEWHERE,” Alice added as an explanation.
“Oh, you’re sure to do that,” said the Cat, “if you only walk long enough.”
From that simple conversation comes a basic tenet of purpose; If you don’t know where you want to go, what you want to achieve, you don’t have to choose a path.