The best lies have a ring of truth to them. Something that seems right which disguises the lie so well that it makes it hard to argue against.
Take Fonzie. Everyone says that Fonzie is cool, and it's easy to fall for the lie. After all, he rides a motorbike, has immaculate hair, and can control a jukebox with his fists. Everyone knows that Fonzie is cool.
It's a lie. Fonzie isn't cool. His best mates are Potsie and Ralph Malph. Schoolkids. Fonzie himself is a high school dropout and is now a mechanic (honest, but not a dream occupation). He's always got a different girl, which makes me wonder why they don't hang around. And the only thing more pathetic than living with your parents is living with your teenage mate's parents.
So keep that in mind; a good lie always seems to be true. And the three biggest lies in roleplaying all seem true, in their way.
Lie #1: "It's only a game." AKA "We're all here to have fun."
This is usually said for the right reasons. Nobody wants to see somebody getting angry and upset because of roleplaying. If your character has died, it's unacceptable to have a tantrum in your buddy's kitchen. That's far from cool. So someone will say, "Hey dude, it's only a game. Chill out."
And they'd be right in that regard. I'm never going to advocate immaturity.
But keep in mind that roleplaying isn't just a game. It can be, if that's all you want. But it can be so much more. Roleplaying can (if done in the right way) be art. Or education. It can be a powerful immersive experience drawing on literary conventions. It can, at times, change your life.
It doesn't HAVE to do that. Some people only want their entertainment to be fun and light. But others are happy to go further.
Roleplaying can be an artform, not just a game. It can be like TV, literature, film, or theatre. These aren't always "fun and games". I didn't find Breaking Bad, 1984, Requiem for a Dream or The Laramie Project "fun" experiences. But they enriched me.
The best times I've had in roleplaying have been when it becomes more than a game. When we've been emotionally and intellectually affected by the stories and characters we've created together. This isn't always fun but it is incredibly satisfying, and at such a stage there's no sense of competition. It's art. And a very unique form of art at that.
We shouldn't be afraid of letting roleplaying become more than a game.
Lie #2: "It doesn't matter what system we use as long as we're all enjoying ourselves."
I've already covered the second part of this statement in the previous point. It's the first section that's more important.
The person saying this just wants to roleplay. And that's great. They're happy just to get into the experience and aren't fussed about what conventions are being used, and that openness is fantastic.
But it does matter what system you use. It matters what conventions are being applied. Because these create the structure for your mutual experience and form the borders of your creative agenda.
Whether you are playing D&D, FATE, Burning Wheel, Call of Cthullu or a systemless game, the structure of the system (or lack of it) will affect how each player (and GM) interacts with the experience. It puts restrictions on the fiat and malleability of the storytelling. And it encourages certain behaviour.
I watched a 5th ed D&D review recently where the reviewer made a great observation. He mentioned that many people (myself included) criticesed 4th ed for lacking roleplaying. He said that he didn't previously put much weight on that argument because he felt that there's as much roleplaying in any game as the participants want there to be. You just ditch the rules and start roleplaying. You don't need rules to roleplay.
But then he read 5th ed and saw how a game can encourage you to roleplay. 5th ed (NB: at the time of writing, the new Player's Handbook is about to be released) has stuff like character goals ("Avenge my father") and backgrounds ("I used to be an alcoholic") and other things like that which encourage you to roleplay. Suddenly he saw how the rules of a game can aid, assist and promote roleplaying.
Different games will encourage different styles of roleplaying. Running Microcosm is a totally different experience to running Hackmaster. Wraith is different to Deadlands, as Pendragon is different to Legend of the 5 Rings, as PDQ is different to Warhammer Fantasy.
If it doesn't matter what system you use, then why not use a better system? Don't be satisfied with a poor fit.
Lie #3: "You can't make a proper judgement on a game until you've played it."
This is the "fair go" argument. It's usually used against people who have read a game and disliked it, so don't play it. After all, games are usually different in practice than in theory.
It's a fair argument in its way, but it's rarely true. I've played a lot of systems and I've been more likely to be underwhelmed by something in play that looked good on paper than impressed by something I expected would be crap.
The way a game system presents itself gives a very clear indication of what the experience will be like. Hell, even just looking at a character sheet will tell you a lot about the experience. If the sheet has a list of ten different combat skills with ratings between 1 and 10, a picture of a human form with different sections to track wounds, and three different boxes to track ammo types, I'm pretty sure that this is gonna be a combat heavy game and it'd be a good idea to get some dice out from the kit. On the other hand, if it just has a list of personality quirks and sections to write down opinions about various characters, I'm gonna be playing a different kinda game (see Lie #2).
I don't need to sit down for three hours and play a game to confirm what I already know from reading the rulebook. The book itself will give me a pretty good idea as to what experience I'll have.
In one of the earliest incarnations of D&D, all weapons did 1d6 damage. That might seem odd, but then keep in mind that if you were using a two-handed weapon you could only attack every other round. There's no advantage. Do you really need to sit down at a game table to confirm that something is wrong there?
Occasionally, but not very often, a game will surprise you. Something that looked bad will actually be kinda awesome. But just because the Fonz has the occasional good line doesn't mean that he's gonna move out of the Cunningham attic any time soon.