Could you spot a con artist?

If you answered yes, you have just provided definitive proof that you are a potential victim. Remember, the "con" in con artist stands for confidence. Not only does the scammer gain your confidence that he is telling the truth, he also exploits your confidence in yourself.

"We're very good at being objective about others, but not about ourselves," said New York psychologist Maria Konnikova, author of the 2016 best-seller "The Confidence Game: Why We Fall for It ... Every Time." "So oftentimes people say, 'if it's too good to be true, it is, get out.' But that's very easy to say about other people, it's really hard to say about ourselves because nothing's too good for me, I'm a person who really deserves this."

That is one reason people were so quick to believe former college and pro football star Art Schlichter, who is profiled on the next episode of CNBC's "American Greed." Schlichter falsely claimed to have connections for discounted sports tickets that he could resell at a profit. He just needed investors to help him buy the tickets. Of course, there were no connections and no discounted tickets. The money went instead to feed Schlichter's gambling addiction.

Today, Schlichter is serving a 10-year federal prison sentence after pleading guilty in 2011 to three felony counts. A judge ordered him to pay $2.2 million in restitution to his victims, who included a wealthy socialite whom Schlichter ultimately convinced to help with his scam.

"I couldn't say no. I could not say no," said Anita Barney, widow of a former Wendy's chairman, in an interview with "American Greed." Barney eventually helped the feds to make their case against Schlichter, but she ultimately was charged with theft, sentenced to three years probation and ordered to pay $400,000 in restitution.

Head games

To understand how a seemingly rational person like Barney — and dozens of others — could be taken in by an inveterate gambler like Schlichter, we asked Konnikova to help get us into the head of a con artist and show us what tricks to look for.

"The first thing that con artists do when they're trying to con someone isn't a trick so much as research. So they really look up the people that they're going to be conning," Konnikova said.

That helps explain why Schlichter showed up for his first meeting with Barney carrying a bag of Wendy's hamburgers.

"He brought Wendy's and that's how he got his foot in the door, basically," Barney recalled.

After that, the con artist reaches into his bag of tricks.

"They will use — and this is a trick — they will make you emotional very, very quickly," Konnikova said. "Because the way that our minds work is, it's very difficult to be logical when you're also emotional."

The emotions can involve fear about missing a potential opportunity — "the fear of missing out, that fear of regret, is really, really strong," she said. Or they can involve a transition. Barney was still adjusting to the loss of her husband.

"People who are in moments of transition are particularly vulnerable to con artists because transition creates emotional vulnerability because it creates uncertainty, and we really don't like uncertainty," Konnikova said. "They're going to sell you certainty."

Konnikova says avoid making big decisions during times like these. Also, think twice before posting information about your transition online. That can be like an invitation to a con artist looking for an easy mark.

Just say no

Other tricks of the trade: some con artists will give you lots of information quickly. We naturally do not like friction, so there is a tendency to just go along.

"We often can't say no because it puts us in this situation of a bad guy," she said.

To guard against those techniques, Konnikova says learn to look at yourself in the third person. Think about what you would advise a friend or relative who asked you about the sales pitch.

"If John came up to me and said, 'Oh, this has happened, it's so exciting,' what would you say to John? Would you say, 'Oh my God, I'm so excited this has happened for you, this is amazing,' or would you say, 'Um, I see a few problems with this, I see a few red flags, maybe you need to take a step back, maybe you want to reconsider.'"

Perhaps most important, learn to say no — which for many of us does not come naturally.

"Basically have exit scripts for any situation in your mind that are automatic rather than in the moment because it's really hard to think in the moment."

And remember, a good con artist is good for a reason.

"The best ones? There are no red flags, they're just great, fun people," Konnikova said. "That's why they're so good. If they were sleazy, if they seemed like a used car salesman like our stereotype of them, they wouldn't be good con artists. We would never fall for them."

In other words, don't be so confident that you can spot a con artist. It could lead to the kind of overconfidence that threw Schlichter's victims for a terrible loss.

See how authorities finally brought down crooked ex-quarterback Art Schlichter on an all new episode of "American Greed," Monday, July 24, at 10pm ET/PT only on CNBC.