Have people been laughing since the beginning of time? Picture cavemen guffawing at some poor dolt whose meat fell off the stick into the fire. As far as archaeologists can determine, no caveman served as the honorary stand-up comedian, and there was no formal comedy culture we are aware of from that period, but if something is funny you have to laugh, right? Laughing at the foibles of others is as old as humanity.
So, what is comedy? What is funny? Comedy is not a science, it's art. Therefore there are no rules and it can be very subjective. What one person finds funny another might cringe at.
Drama is based on conflict. So is comedy. The joke hits us by delivering something different than what we expect—in other words incongruity. You are creating an expectation and then BAM! You throw a curve ball—the punch line! Result: Big laughs (you hope). Comedy comes from incongruity and surprise, but it also needs perspective to fit into the situation or environment.
It’s important to play to your audience and the context in which you’re playing. One person who was great at this was Tommy Cooper. Here's one of his that I love: I had a rocking horse once, and it died. Fabulous!
A young crowd may not understand the same reference that an older crowd would. You could bomb completely simply because you weren’t considering that the graduates of the Class of 2013 don’t relate to a reference to hippies. And a senior audience doesn’t relate to a joke such as: (Twitter-head explaining to a newbie) “Okay, let me paint a picture in your head... Twitter is like cramming 140 of the wackiest characters you know into a little room with turquoise walls, and then asking them to sing like the Birdman of Alcatraz in falsetto.” The first half might escape an older crowd, and the latter half might escape the younger crowd. In the same way, a sophisticated white collar crowd might not appreciate redneck jokes, and heck, rednecks might not even appreciate redneck jokes. Point being, know who your audience is.
So, our formula comes out:
Incongruity + Surprise + Context = Funny
The irony of comedy is that funny things are not really incongruous. Writers put them in the wrong place for the right reason: To create a joke that makes you laugh. While most of the world looks at things in the normal way, the comedian must look at things differently to know how to change things just enough to make them funny. You don’t want to change them too much or even too subtly or your effort might slide into confusing nonsense.
For example, Abbie Hoffman played to his young activist audience in the sixties when talking about first amendment rights by saying, “Free speech means the right to yell ‘theater’ in a crowded fire” (a type of joke called a flip which we will discuss later). It refers to a court ruling from Oliver Wendell Holmes speaking to what could be dangerous free speech, “Like yelling ‘fire’ in a crowded theater.” Hoffman made an astute observation by simply flipping the words “theater” and “fire.”