"The story actually started with a terrible moment a dozen years back during the invasion of Iraq when the helicopter we were traveling in was forced down after being hit by an RPG. Our traveling NBC News team was rescued, surrounded and kept alive by an armor mechanized platoon from the U.S. Army 3rd Infantry."

-- NBC anchor Brian Williams,

recounting his 2003 brush with death in Iraq.

Except, as the whole world now knows, none of that ever happened. Brian Williams was not aboard the helicopter that was forced down by Iraqi fire, although he and his helicopter did happen upon the scene roughly an hour later. He and his NBC crew were not rescued by American soldiers. And after the soldiers involved in that action came forward to challenge Williams' account, he publicly recanted:

"I think the constant viewing of the video showing us inspecting the impact area (of the damaged chopper) — and the fog of memory over 12 years — made me conflate the two, and I apologize."

So now what?

Neuroscientists have long known that the brain can be an unreliable narrator, in ways both large and small. To cite an illustration on the small end of the scale, I've played golf almost every week for the past 20 years with a rotating cast of about two dozen characters. When it comes time to tote up the score on a just-completed hole, one of us will occasionally make a mistake and have to be corrected by his playing partners. We've all done it; we all know better than to take it as an act of dishonesty. It would be a pretty dumb thing to lie about.

But we've also all remarked on the fact that when you make those mistakes, you always err on the low side and never on the high side. You may accidentally report a 5 when you really scored a 6, yet somehow you never report an 8 when your real score was 7. The brain is always willing to twist events to its own advantage.

That said, I don't think you can explain away Williams' story in those terms. It's not like forgetting that first shot that you left in the sand trap. In one retelling in 2013, for example, he recalled "being in a helicopter I had no business being in in Iraq with rounds coming into the airframe," thinking he would die. He has said that "“our captain took a Purple Heart injury to his ear in the cockpit.”

"Memories" that vivid, that detailed and that false are not the result of events fading into time and being misremembered. They are fabrications, and if Williams did not actively invent them he was less than honestly vigilant in fending them off.

And yes, exaggerated war stories have existed from the beginning of time, often related by people who never saw real action but over time convinced themselves to believe otherwise. I'm sure that more than one lowly armor-polisher came home from the Trojan War, crossing the wine-dark sea back to Greece, to regale his drinking buddies about the time that he saved the life of brave Achilles.

The difference is, the lowly spear-sharpener wasn't a network anchor.