Lots of humor
A draft officer was asked: "How do you determine in the Army that your draftees are intelligent enough for service?"
"When the man appears for the examination at the draft board we usually ask him one clever question only."
"What question?"
"We ask him: How long did the Thirty Year War last'?"
"And what?"
"Now we have to think of an easier one- most of the examinees fail to answer."
A candidate for assignment to command a ship in the Navy had to present his reasons for being able to hold his post to a board of examiners in navigation.
"Sir, I would make every effort not to let my ship sink because there'd be a board of inquiry to face; I'd lose my command, perhaps any chance of further promotion, and my personal effects; and, worst of all, I can't swim."