On Oct. 26, 1881, Wyatt Earp and a couple of his brothers, joined by Doc Holliday, brought justice to the streets of Tombstone, Ariz., when they engaged the Clanton and McLaury gangs in the famous “Gunfight at the O.K. Corral.” Or so we’ve been told in movies where Wyatt Earp was played by, among others, Burt Lancaster, Henry Fonda, Kurt Russell and Kevin Costner, while his adversaries have been portrayed as thuggish oafs.

You don’t have to do much digging to find out that it wasn’t that simple. To begin with, Virgil Earp led the fight that day, since he was city marshall. Wyatt was along for the ride, but was no lawman. (Because of this, Wyatt was charged with murder following the incident, though he was not indicted.) Secondly, at least one member of the group gunned down by Earp and Co. was unarmed, making the events of that day less a fight than an execution. Thirdly, the opposing groups represented different political factions, each intent on making Tombstone its turf. Fourthly ¼ well, you get the idea.

All these things are established fact. As Casey Stengel used to say, “You can look it up,” and if you did, you would find that the “Gunfight at the O.K. Corral” (which did not actually happen at the O.K. Corral, but in a vacant lot nearby) was, at best, a controversial battle in which neither side was clearly right or wrong. If doing research sounds dull, you might prefer to catch the lecture at 7 p.m., March 13, by writer John H. Ziegler at the Foothills branch of the Glendale Public Libraries. A former college professor who now lives in Tombstone, Ziegler will examine the facts of what happened that day, which in no way conform to the movie myths. The library is located at 19055 N. 57th Ave. in Glendale. Admission is free.

If you go hear Ziegler, or if you spend a few hours researching online or at the library, you may well come away knowing that the Gunfight at the O.K. Corral was not a gunfight, not at the O.K. Corral, and did not involve “good guys” versus “bad guys.” But here’s the rub:

You won’t believe it.

Knowing something and believing it are different things. Knowledge is information, facts, stuff you can verify. Belief is a feeling. It’s an emotional conviction that something is so. You know the facts. But you believe the truth–and the truth doesn’t necessarily correspond to the facts.

We may know all sorts of facts about an event like the O.K. Corral, but we still believe that heroic lawman Wyatt Earp strode into a rain of fire from heavily armed villains because art–the movies–tells us it is so. Art has at its disposal one of the greatest powers imaginable: the power to make us believe.

Art does this, not by persuading us of something we don’t know, but by confirming as beliefs things we already think we know. “Hamlet” doesn’t persuade us that choice is a dangerous thing. In Shakespeare’s play, the title character dilly‑dallies over killing his uncle because he feels he might be mistaken about his uncle having murdered his father. When we see “Hamlet,” we already know it’s a tough call to take action on a supposition. We don’t learn that from the Prince of Denmark. But we do come out of “Hamlet” believing it, feeling it, deep inside our souls.

On March 23 and 24 at the Scottsdale Center for the Performing Arts, the Actor’s Gang will perform a staged version of George Orwell’s cautionary novel, “1984.” Publicity for the production states: “Imagine a world where people fear that their opinions cannot be expressed freely, where leaders are not held accountable for their deceptions, where perpetual war is waged against an unseen enemy; a world where ignorance is strength, freedom is slavery and war is peace.”

Yeah, yeah, we get it: All those things apply to our country in the year 2007. We know that. We just don’t believe it. And we won’t, as long as we’re distracted by reality TV and fine dining. But if something such as a movie, a song, maybe even a production of “1984,” ever grabbed the public by the throat and made them feel the things they already think, then we’d believe it, and the social climate would change dramatically, the way it changed when protest songs targeted the Vietnam War in the 1960s.

That’s why governments censor. There’s a lot more at stake than dirty words.