The Neuroscience of Cons


The key to a con is not that you trust the conman, but that he shows he trusts you. Conmen ply their trade by appearing fragile or needing help, by seeming vulnerable. Because of THOMAS [The Human Oxytocin Mediated Attachment System], the human brain makes us feel good when we help others—this is the basis for attachment to family and friends and cooperation with strangers. “I need your help” is a potent stimulus for action.

This is interesting. They say that all cons rely on the mark’s greed to work. But this short essay implies that greed is only a secondary factor.

Posted on November 18, 2008 at 6:32 AM32 Comments


Zach Beane November 18, 2008 7:41 AM

Mamet’s “House of Games” explored this notion with, for example, the Western Union con.

christopher November 18, 2008 8:04 AM

This is fascinating, and helps to explain why I am so mean to people appearing fragile or in need of assistance. I have a chemical imbalance!


Xyz November 18, 2008 8:16 AM


Actually, according to the professor of “neuroeconomics” who wrote the article, you are a:

“My laboratory studies of college students have shown that two percent of them are “unconditional nonreciprocators.” …This means that when they are trusted they don’t return money to person who trusted them… What do we really call these people in my lab? Bastards.”

Eric November 18, 2008 8:21 AM

I think the reason ‘they’ say “cons rely on the mark’s greed to work” – or – “you can’t con an honest man” is because in the stories you want the con to be a likable fellow. But most cons have a hook that involves helping someone out (first) with the promise of possible gain (second) if you do. Look at the letters from Nigeria – it always starts with a plea for help, or at least some story about the untimely death of someone.

In reality, it’s easier to con an honest man – they usually don’t think that you might be getting ready to con them!

Joseph November 18, 2008 8:38 AM

I’ve noticed that the “Can you help me” line works great in the office, too. If you phrase all your requests with “Can you help me?” people are much more likely to do them than if you just ask politely.

A nonny bunny November 18, 2008 8:53 AM

The illusion of control is also very important, I think. If you don’t trust the conman, and don’t have the illusion of control, then whether he trusts you or not you’re much less likely to risk it.

Impossibly Stupid November 18, 2008 9:01 AM

It’s been said that altruism is actually a form of emotional greed, so maybe we can just say that nothing is as obvious as some would like to believe. In that regard, the key to a con is you trusting the conman; it’s that misplaced trust that allows them to get whatever it is they’re after. The fact that they may do it by feigning trust or exhibiting some other weakness isn’t particularly interesting, is it?

A nonny bunny November 18, 2008 9:07 AM

“If we humans have such big brains, how can we get conned?”

And the funny thing about that is, if we didn’t have such big brains, we probably wouldn’t get conned. Most animals don’t have the imagination to be conned, nor the patience. You’d have to trick them with what’s right in front of them, and not with a future payoff that they then never get.

Particular Random Guy November 18, 2008 9:21 AM

Shouldn’t elderly people then be able to countercon the con by being in need of help? 😉

John Moore November 18, 2008 9:38 AM

Spies and conmen already know this. In the show Burn Notice, the main character is always conning bad people into trusting him. There’s a quote in the show: “Con men do it for the money. Spies do it for the flag.”

AlanS November 18, 2008 10:01 AM

“…the human brain makes us feel good when we help others”. This strikes me as a restatement of The Theory of the Modern Sentiments (Adam Smith, 1759; also Wealth of Nations, 1776) or for that matter most of the social theory on reciprocity since. What’s added is the chemical underpinning and the twist that maybe there are a few “ruffians” totally without it and willing to exploit it in others.

“How selfish soever man may be supposed, there are evidently some principles in his nature, which interest him in the fortune of others, and render their happiness necessary to him, though he derives nothing from it except the pleasure of seeing it. Of this kind is pity or compassion, the emotion which we feel for the misery of others, when we either see it, or are made to conceive it in a very lively manner. That we often derive sorrow from the sorrow of others, is a matter of fact too obvious to require any instances to prove it; for this sentiment, like all the other original passions of human nature, is by no means confined to the virtuous and humane, though they perhaps may feel it with the most exquisite sensibility. The greatest ruffian, the most hardened violator of the laws of society, is not altogether without it.”

Seth Gordon November 18, 2008 10:02 AM

Zach, above, mentions Mamet’s House of Games. At one point, the con man in that movie tells the main character, a psychiatrist: “Does he give me his confidence? No, I give him mine.”

christopher November 18, 2008 10:19 AM


Nah, you’re only tagging me with “bastard” because the article didn’t provide another alternative. Maybe I’m allergic to THOMAS, not immune.

scote November 18, 2008 10:30 AM

“they say that all cons rely on the mark’s greed to work”

I think “they” say that to make it easier to blame the victim. Even a cursory examination of cons shows that idea to be false. Many cons appeal to people’s desire to be helpful. The Bank Examiner con, for instance, is a con where the desire to help authorities and to do the “right thing” is the motivation.

Mister Paul November 18, 2008 10:35 AM

Fascinating. Can anyone name a book about cons that is engaging, well researched and informative?

John November 18, 2008 10:58 AM

@ “They say that all cons rely on the mark’s greed to work. But this short essay implies that greed is only a secondary factor.”

Different scams for different targets for different motivations. Greed, goodwill, fear, shame, weakness, etc.

If someone puts on a Santa suit and rings a bell, then keeps the cash, their con is based on good-will. Likewise anyone who set up a false 9/11 fund.

If someone promises huge returns if you just send your money to a nigerian acocunt, it plays on greed, and perhaps also the fear people have of not having enough retirement.

Some cons also just take advantage of stupidity.

Clive Robinson November 18, 2008 11:15 AM

@ Bruce,

“The Human Oxytocin Mediated Attachment System”

Didn’t you blog about people taking Oxytocin by nasel spray just a few months back?

And the fact it made them more trusting of others (and If I remember correctly got a few ribaled comments about wives and girlfriends…).

Trichinosis USA November 18, 2008 1:16 PM

…This means that when they are trusted they don’t return money to person who trusted them… What do we really call these people in my lab? Bastards.”

Ah, those poor, put-upon, fragile, in-need people in his lab; to whom, apparently, money was not returned. ;-7

inSecure November 18, 2008 3:14 PM

Wow , great post , but you can learn more in the Mitnick’s book , about social engineering. Another move to watch is the “STing “, “Confidence” and “Shade ” , both greate movies. November 18, 2008 5:36 PM

I’m surprised it’s taken this long for anyone to study this. It’s common knowledge amongst merketing types and other con-men that cupidity is uncertain, but the need to good is a basic part of our social nature.

paul November 19, 2008 10:31 AM

I think it’s hard to separate the greed and the altruism in a lot of cons. The come-on is typically a chance to do good at a very low cost in time and effort, plus (usually) a profit in cash.

Pete Austin November 19, 2008 12:44 PM

Exactly right. A common example is pretexting, where the crook convinces support staff to supply them with information or passwords by acting friendly and helpless. There’s no financial benefit to the victim.

Tr0ix November 19, 2008 1:10 PM

Another good book or books is “The Mystery Method” or “the Game” or any of the common pickup artist texts.

Afterall how far is “Social Artist” from Social Engineering or Con Artist?

I believe they even admit to using some of the trademark talents that con artist use such as cold reading and a type of trance or hypnosis.

Ricky November 20, 2008 9:59 PM

There’s some confusion here – the truly honest man isn’t more vulnerable to such cons than others because such a man doesn’t fall for the notion that anyone else needs his help. So he (or she) won’t fall at the first hurdle as the less-than-honest person does. Secondly, the truly honest man has no attachment and therefore no deficit in oxytocin. So he/she doesn’t experience a strong impulse to help (which in others comes from the need to feel valued by others – as shown in Maslow’s hierarchy).

So Eric, yes, its true that the honest man doesn’t project dishonesty onto others (and hence be suspicious), but he has other ways of avoiding being duped!

JB November 21, 2008 4:18 PM

@Ricky I don’t agree with either of your points.

In regards to your first point… Are you seriously saying that to be truly honest a person must feel no inclination to help anyone, under any circumstances? That to be honest, I must actually believe that a person who is on the ground bleeding, or other obvious physical distress, doesn’t really need someone’s help? This may sound like I’m exaggerating, but the point of the blog entry was that con-artists abuse the same psychological process that is involved with the scenario I present.

Your second point is even more illogical, given the research presented by the author. His studies show that interest in other people are cause by a properly functioning oxytocin release system which rewards trust, analogous to a quickly on, quickly off switch. Thus, Oxytocin isn’t supposed to be present in large quantities over long periods of time. If it is that means there’s a neruochemical imbalance, which would cause the reward mechanism to fail because of the lack of contrast. So unless you are proposing that the only way to be a truly honest person is through brain dysfunction, you are misunderstanding the material presented.

In summary, trusting no-one is more a sign of paranoia than honesty. Not everyone is out to harm you, and believing otherwise is just as faulty as believing that no-one wants to harm you. In the long run, both beliefs are inherently self-destructive, albeit in different ways.

Eric November 23, 2008 5:55 PM

I agree with you, JB. I don’t know what Ricky has read, but the ideas he’s parroted are so flawed, he’s certainly already been conned by someone.

Ricky November 23, 2008 10:44 PM

@JB no surprise you don’t agree. But then you seem to have misunderstood, so I’ll try to set it out again with more detail.

No, I’m not saying what your paraphrase says, I’m saying that its the nature of a truly honest person to be at choice about ‘helping’ another person. So in your version, you have it the wrong way around – you can’t be (become) ‘truly honest’ just merely by making a single behavioural choice. Rather I’m saying that once one has become (by a process of some therapy, or whatever religious/spiritual path) truly honest, one won’t feel there’s a need to help anyone. Yes, such a person is free to ignore someone in physical distress – it may be that that person has to be ignored in order to help someone else in greater distress for example. No, I’m not saying you must not ‘believe’ that that person is not in need of someone’s help – that again is not what I’m saying.

So no, my point is not as you imply illogical, its rather perfectly reasonable – its only your strawman variant of it which is illogical.

Your second point is also not what I’m claiming (actually rather observing). I am saying that its the nature of detachment (synonymous here with total honesty) not to experience emotional disturbances in response to phenomenal events. I take it that the author’s studies haven’t been of detached individuals, rather ‘normal’ people.

Are you saying I’ve suggested ‘trusting no-one’? If so, where? I agree that trusting no-one is a sign of paranoia, not honesty. I also agree that not everyone is out to harm. So where have you got these ideas, if not from me?

@Eric – do show the flaws in the ideas I’ve offered and produce some justification for your claim that they’re ‘parroted’.

Bink November 29, 2008 2:29 AM

This is one of the premises of ‘Gate of Angels’ by Penelope Fitzgerald; not a book about cons, but it is full of perceptive ideas.

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