Up until the late 70's, stand-up comedy mainly was performed in night clubs based in resorts and casinos. A fair segment of the comics were typlified by Milton Berle, who proudly admitted that he was a joke thief. Jokes were almost like musical standards, with many of the top comics putting their own spin on them. Berle was loved so much that he became like a member of the family to TV audiences who referred to him as Uncle Miltie. Stand-up comedy at the time was based on one-liners and "joke jokes." (these are also referred to as street jokes. The jokes you will hear at work or have forwarded to you in an email.)
An evolution began to happen in the 60's, as comics like Lenny Bruce and Mort Sahl challenged societal conventions with their material. George Carlin and Robert Klein were influential in evolving stand-up even more during the 70's. Richard Pryor, who did mix in some "joke jokes" in his routine, when playing the character Mudbone, eventually joined these comics in turning the art form on it's head. Pryor brought his own personal tragedy into the equation to make for some of the dyamic performances ever presented on a comedy stage.
By the 1980's, comedy clubs were popping up all over the country, as demand was ahead of supply when it came to top-notch stand-up comics. The comics who did have unique acts, like Leno, Seinfeld, Richard Lewis, Paul Reiser, Roseanne Barr, etc. transitioned into sitcom stars. There was a real feedling frenzy, with Networks offering high dollar development deals to comedians, if they were ready or not. The success of the previous mentioned and other comics like Tim Allen and Drew Carey made the Big 4 believe that stand-up comics were good bets to create success in the medium. (This feeding frenzy is comparable to what was happening in the Seattle Grunge scene, with Music companies throwing money at everything, hoping to catch the next high riser.)
While I wouldn't say these comics were much better than a lot of the acts today, they did leave a hole in the business, as they were the best of the "observational", more middle of the road comics. Ray Romano was one of the last of these comics and my guess is that "Everybody Loves Raymond" will be the final sitcom of its type to achieve large success. The quality comics that were left were mainly edgier, in your face acts or stand-ups who embraced more surreal-based material. This is still how it pretty much is today in the business. These are my 2 favorite styles of stand-up comedy, but are hard to transition into a family-style sitcom.
Sorry for those of you that weren't interested in my short histoty of stand-up comedy, but I feel a little background is needed. Stand-up comedy is an entertainment art-form that I wouldn't recommend to anyone wanting a stable lifestyle. I would hazard a guess and say that fewer than 200 people in this country make more than $50,000 dollars a year simply performing stand-up. The comedy boom is over and the booking agents are in the power position when it comes to neogotiating, except for a select few major draws. Unlike music, where some emo group can put out some derivative drivel and wind up on the cover of numerous magazines and late-night talk shows, many really creative and intelligent stand-ups are lucky if they can consistently get bar gigs which will pay them enough to stay ahead of their creditors. Unlike other "artists" who can apply for government and private grants to supplement their efforts, stand-up comedy is disrespected by most of the creative community, seen as something not much above professional wrestling or community theater.
I'm not going to claim I don't have some bitterness over how my profession is perceived, but since I went into the business with few blinders to what I would be facing, I try not to complain about what I do. I like my job most days and I'm happy that each night I can go up in front of a live audience and share my own original thoughts, while making a pretty decent living doing it. (It took me 10 years to get that "decent living" point.) Even the nights when I'm in a less than optimal situation, dealing with bad lighting and sound equipment or having to conduct an assault on some drunken heckler, I know there will be some moment of adrenaline that will rush through me that I couldn't get at almost any other profession.
So with this bit of background, let me address the idea that using other people's material should be condoned. In no way should it be accepted. There will be times when parallel construction will happen, but when the blatant stealing happens that was outlined in the previous post, everyone aware of it needs to stand-up and denounce it. The idea of actually giving credit to the person you are ripping it off of, like you are footnoting it in a book, is a ridiculous concept. First off, it would wreck the momentum of the comic, as stand-up is about presenting a show that comes from you. Add to this that performing stand-up comedy was just about your skills as an entertainer, the profession would solely be made up of actors. These are called one-man(or woman) plays.
Let me finish by mentioning that I sadly was nervous about posting my original piece on the subject, as I know some management types in the entertainment field have little interest in who is original and who is a plagiarist. The main focus is don't get in the way of the financial gravy train. Since most of my Hollywood dreams are pretty much over I figured I should at least use my little soapbox here to enlighten a few more. I really admire Joe Rogan for his stance on this subject, if he is financially set for life or not. I'm just a guy who mainly headlines Triple A comedy clubs. I recieve great marks after most of my performances, but I can draw very few people to see me. There are very few comics who can. My hope is that if enough people become aware of the duplicity that goes on, some of these comedy thieves will stop their theft and actually spend some of their ill-gotten riches on writers who can craft some originality back into their shows.