Once upon a time there were two young men, Dib and Dab, who woke one morning to find themselves enclosed by an very high brick wall. Being a man of action, Dib reached down, grabbed a rock and began to pound at the wall. Day after day he pounded, chipping away ever so slowly. Meanwhile, Dab ran hither and yon about the enclosure.
"Dab," said Dib, "come join me and together we'll chip our way through."
"No thanks," said Dab. "I've better things to do."
"And what might that be?" Said Dib. "Running around all day while I alone work patiently at getting us out of here?"
"Perhaps." Said Dab.
The months flew by. Dib kept chipping away, making scant progress, while Dab continued to run. Finally one morning Dab approached Dib and said, "Well brother, today is the day!"
"And what, pray tell, makes this day so different from all the rest?" Said Dib.
Without saying a word, Dab, whose legs had grown very strong, stepped back several paces, then ran forward and jumped over the wall.
Speechless, Dib stood and stared at the top of the wall where Dab had jumped over. After some time he picked his stone back up and resumed chipping.