Abramah Lincoln*: 3 birds on a fence
Abraham Lincoln* supposedly would ask this question when he met people for the first time. Many regard it as a sign of quirky humor, some suggest he was using it to learn how people thought:
“there are three birds on a fence, if I shoot one, how many are left? ”
* I have been pointed out that this joke may have been attributed to Lincoln because of a quote about the civil war, but the joke looks to be perhaps much older. Lincoln was well known for his humor, deliberately putting people off their guard Abraham Lincoln’s Stories and Humor – Abraham Lincoln’s Classroom so it would be within his style, it’s just not clear if he used this particular joke outside the context of a civil war quote.