Once upon a time there lived three men: a doctor, a chemist, and an engineer. For some reason all three offended the king and were sentenced to die on the same day.

The day of the execution arrived, and the doctor was led up to the guillotine.

As he strapped the doctor to the guillotine, the executioner asked, "Head up or head down?"

"Head up," said the doctor.

"Blindfold or no blindfold?"

"No blindfold."

So the executioner raised the axe, and z-z-z-z-ing! Down came the blade--and stopped barely an inch above the doctor's neck. Well, the law stated that if an execution didn't succeed the first time the prisoner had to be released, so the doctor was set free.

Then the chemist was led up to the guillotine.

"Head up or head down?" said the executioner.

"Head up."

"Blindfold or no blindfold?"

"No blindfold."

So the executioner raised his axe, and z-z-z-z-ing! Down came the blade--and stopped an inch above the chemist's neck. Well, the law stated that if the execution didn't succeed the first time the prisoner had to be released, so the chemist was set free.

Finally the engineer was led up to the guillotine.

"Head up or head down?"

"Head up."

"Blindfold or no blindfold?"

"No blindfold."

So the executioner raised his axe, but before he could cut the rope, the engineer yelled out:

"WAIT! I see what the problem is!"