This is world's greatest con. I'm Brian Brushwood.

What makes people lie? Why would any of us willingly deceive somebody? Do we do it

for panic, greed, sometimes, sure? But not every lie has a clean cut motivation. Sometimes

things are messier. So let's ask another question. What is a lie? A lot of people think

it's saying the opposite of the truth. I have a hand behind my back and I have three

fingers held out and I tell you I have anything other than three than I'm lying.

But am I lying? Maybe I am. Or maybe I legitimately meant to put up another

number and accidentally put up three. Or maybe I got confused with another number and

misspoke. Would that be a lie? We spend a lot of time in our modern culture talking

about truth and facts. But the reality is that these things are far more complicated than

a cable news kairan would lead you to believe. Think about the stories we've told so

far in this season. Do you think Dan and Wright has a different

version of the story of 21 than we told? Of course he does. And I bet you'd hear a lot

more complicated version of the story from Michael Larson when we talk about the Press

Your Luck scandal. Harry Ketchum on Super Password, the Ingram gang from who wants to be a millionaire,

all of them are going to have stories different from the ones we've told. Now we've done

our due diligence on all of these stories and even tried to represent the points of view

of these guys. But if they told you something different against all the evidence that we

could find, would that make them liars? Let's flip it if you believe them would it make

me the liar? The reality is that the truth of these stories will always be an amalgamation

of perspectives holstered with whatever physical evidence can back it up. A lie is simply

the one you don't believe and the truth is the one you settle on. Some situations are

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