The Psychology of Con Men


My all-time favourite [short con] only makes the con artist a few dollars every time he does it, but I absolutely love it. These guys used to go door-to-door in the 1970s selling lightbulbs and they would offer to replace every single lightbulb in your house, so all your old lightbulbs would be replaced with a brand new lightbulb, and it would cost you, say $5, so a fraction of the cost of what new lightbulbs would cost. So the man comes in, he replaces each lightbulb, every single one in the house, and does it, you can check, and they all work, and then he takes all the lightbulbs that he’s just taken from the person’s house, goes next door and then sells them the same lightbulbs again. So it’s really just moving lightbulbs from one house to another and charging people a fee to do it.

Posted on October 20, 2008 at 5:57 AM37 Comments


BF Skinner October 20, 2008 6:50 AM

I’ve often thought how a course in avoiding the con would help reduce users’ exposure. Most of what I see on a daily basis are just online versions of old cons (phish email = imitative deception, and the spanish prisoner is now 419 fraud emails). Is there a course in it? Police I’ve spoken too have an attitude like some people we all know. They don’t want the methods and tools of con’s to be widely known in case in creates new cons.

Tim October 20, 2008 7:02 AM

Just watch The Real Hustle!

Great show. Lots of the scams are very clever (and some are clearly over-elaborate-for-TV), but some just make me depressed about people’s gullibility. Especially the black money scam.

Evan October 20, 2008 7:49 AM

Replace every single light bulb in a house? What with having to unscrew light fixtures and stuff, how fast can you possibly do that? Are we only making $5/hour with this con?

Ambrose October 20, 2008 7:54 AM

It says “in the 1970s” right there in the quote! $5 was worth more, and probably light bulbs cost more too.

Sparky October 20, 2008 8:28 AM

Here, in the Netherlands, we have a TV show called “oplichters ontmaskerd”, which roughly translates to “con-artists exposed”, in which they don’t actually catch con-artists, but they actually scam people in various ways, usually very simple.

The money or property is of course returned to the victims afterwards, who often talk about what happened. Very often, people will say that they always thought they wouldn’t be fooled.

One very simple scam I remember they did recently, was a fake doorman, standing in front of expensive hotels. Every single guest that arrived handed over their bags, which of course disappeared along with the doorman. The man was just wearing a long, black coat with a gold-colored name tag. If guests wanted to carry their own bags, he said that he had to be seen doing his job, at which point not a single person refused.

Hans October 20, 2008 8:53 AM

Sparky: There are several of these shows in several countries. They are usually modelled after the already mentioned “The Real Hustle” from BBC. Quite revealing they also usually show the same tricks with exactly the same results (e.g. they showed fishing valuables through mail slots and they got the same types of items – for example a car key or a house key – in the english, the american and the german adaption of the show. So one can safely assume that the show iss mainly faked.

Hans October 20, 2008 8:57 AM

Oh, but btw in the show itself they claim that what is shown is for real, although for example on the discussion page of the wikipedia entry for the show some people told they acted as extras for the show. So i think the claim that they are showing “REAL hustle” is itself the biggest hustle of the show. Its still quite entertaining TV and most of the tricks will probably work (but often are much investment for uncertain outcome), but don’t believe the claim that what is shown is real.

Pete Austin October 20, 2008 9:21 AM


What you see is a mixture of real and fake. They first do the scams for real, then after they get the victims’ agreement, they re-enact them to get additional camera angles and better sound. The result is not 100% real, but it’s an honest attempt to show what really happened.

crossbuck October 20, 2008 9:59 AM

I’ve seen people get taken by the sweepstakes con, so anyone who’s desperate enough (or greedy enough) can get conned. Even me, I suppose, in the right circumstances.

I could even fashion a variant of the light-bulb con that might work today. Offer to replace every bulb in a house with a new fluorescent for a low cost ($50?). Say it’s a utility company promotion. Pick a neighborhood with a lot of older houses to do this in. Where do the bulbs come from? Where I am, there are a lot of abandoned houses from the housing crash, so there’s plenty to be harvested from there.

Gin October 20, 2008 10:43 AM

There are a lot of people who think like that all the time. A normal person might look for opportunities to earn honest profit, but these guys are always thinking how they can rip someone off. If it isn’t light bulbs, it’s auto repair, or TV repair. The TV repair guy says it will cost you hundreds to fix, knowing that’s more than a new one costs. So most people don’t even go back to pick it up. Then he swaps parts around and ends up fixing it for zip. Then he sells it as reconditioned. Happens all the time. How many times have you received your old auto parts back after the garage replaced something?

oplichters ontmaskerd October 20, 2008 10:50 AM

They say The Sting is a good movie for the con game but I liked Mamet’s House of Games better.

thiefhunter October 20, 2008 11:04 AM

Cons like these can certainly be amusing—when you’re not the victim. Sadly, most cons these days net much more than $5, and the weakest marks are often targeted. That is, the elderly, in large part. The brilliance of of the con artist is in blending in—as if he’s one of us—and in disappearing without a trace.

One U.S.-based international non-profit group, mostly passionate members of law enforcement, make it their business to find and prosecute the organized crime families that perpetrate these scams.

Chris B. October 20, 2008 12:04 PM

I can see it now: “Take our course on how to avoid cons, for 3 low payments of $149.95…”

Avoiding cons is simple and always will be:
1) Strangers do not want you to have more money. Ever. They don’t want you to save money. They don’t want to give you money. They don’t want to show you how to make money.

They want money for themselves, and they want it to come from you, because it has to come from somewhere and you’re the only two talking.

That doesn’t mean they’re conning you. They could simply be selling you something. You’re free to buy it. But if you think they aren’t profiting off your transaction then you’ve been had.

If a stranger ever initiates an encounter with you, and you think that you’ll end the encounter with more money/property than you started, you’re dumb. If you think you’ll end it with a LOT more, you’re a mark.

Mark October 20, 2008 12:38 PM

One very simple scam I remember they did recently, was a fake doorman, standing in front of expensive hotels. Every single guest that arrived handed over their bags, which of course disappeared along with the doorman.

Or maybe they only showed footage of the scam working. With all so called “reality shows” it’s difficult for viewers to know how much editing even acting might have been involved.

jammit October 20, 2008 2:19 PM

Sell the sizzle, not the steak.
I used to repair TV’s for a living. Sometimes the repair was too difficult or needed too many parts. I would order a rebuilt chassis and send the broken chassis for credit on the core. Basically I’d get remanufactured guts from somebody elses TV, and I’d ship off the bad guts to have repaired to sell to someone else.

King October 20, 2008 2:51 PM

Police I’ve spoken too have an attitude like some people we all know.
They don’t want the methods and tools of con’s to be widely known in
case in creates new cons.

Argh! A perfect example of why “security through obscurity” DOESN’T WORK and youi’re actually better off PUBLISHING the con. If these cons were more widley known, they WOULDN’T WORK.

I wouldn’t have realized he was conning me this way, though. I would have assumed he wanted to case my house. He still doesn’t get in.

Chris B. October 20, 2008 4:25 PM

@Drake: you’ll still lose. Whatever thing of yours they see that they want, if the stranger wanted to pay what it was worth they’d just go buy one.

I’m exempting the occasional moron from this idea, of course you’ll run into one of those from time to time. The trick is for it to not be you.

John N October 20, 2008 5:40 PM

Simple rule for avoiding basic cons…TANSTAAFL – i.e., if it looks too good to be true, it probably is.

Reno October 20, 2008 10:16 PM

I would also rate the film, House of Games
very highly. What you thought was true changed more than a house of new? lightbulbs.

Clive Robinson October 20, 2008 11:18 PM

@ Davi Ottenheimer,

“How many Con Men does it take to screw in a lightbulb?”

Yup the answer is the same as it is for mice,

Two but don’t ask me how they got in there…

crossbuck October 21, 2008 12:33 AM

Every scam involves theft of one kind or another. How do you think the light bulb scammers got their first set of bulbs? Besides which, many abandoned houses/developments have been stripped of their more valuable pieces, and are little more than shells. Most short cons have some element of theft involved.

Sturat October 21, 2008 5:46 AM

I’m always bemused when somebody quotes the railway station survey – people giving up PINs for a free pen.
This seems to be run every year in the UK and people have been asked for PINs, passwords, etc. in return for things like chocolate or pens. One or more of the tabloid newspapers will then run scare headlines about how lax people are.
But if somebody with a clipboard offers me something in return for telling them my PIN or password I’m more than happy to tell them four random digits or a random word and collect my gift! Now I’m sure there are some people who give genuine information, but I’m equally sure a lot of people think the same way as me!

Naveen JP October 21, 2008 6:44 AM

Brain sensors that would sense intentions of people could be a major security device of the future, that could help in such scenarios.

Honest Guv October 21, 2008 4:52 PM

I don’t really like this as an example of a good con.

The essence of a REALLY good con is that the mark must be positioned into a situation where they are getting an unfair advantage by illegal and/or embarrassing means. The point is that the mark should not be able to seek legal remedy for being conned. The light bulb example doesn’t really meet the requirements for me. It’s not enough to rip somebody off – it must be done in such a way that there is no possibility of redress for the victim.

Hence the saying “you cannot cheat an honest man.”

Tarkeel October 22, 2008 1:29 AM

@Honest Guv: I’ve seen one like that making the rounds on different online games, used to sell items way above their actual value.

The premise is that you have some sort of auction system to buy items from, as well as direct trade. The first and costly step is to get an item that is worth buying in the first place. You post this for sale above what it is worth.

You then shout that you want to buy the item for more then what you posted it for. Usually somebody is looking to make a profit, and will try to buy your auction and sell it to you, at which point you just claim that you just got it from somebody else, and are not looking anymore.

The only pepole scammed by this, would be the ones that are trying to rip you off.

Clive Robinson October 22, 2008 3:30 AM

@ Tarkeel,

“Usually somebody is looking to make a profit, and will try to buy your auction and sell it to you”

I like your effective definition of a Con Man as being,

“One who makes money by buying low and selling high”

Yup that covers most Bankers, Traders and Middle Men nicely 😉

oplichters ontmaskerd October 22, 2008 6:55 AM

But the article says you can cheat honest people who AREN’T out to make a money. and so did the Bunco web page cited above (really good thanks!)

Scams target differnt human failings don’t they? Isn’t that why they translate so sucessfully online. Of course the Advance Fee Fraud attacks our greed, but the emails that claim to show Bin Laden dead, assure you that the child porn you ordered is on it’s way, or the disaster relief scams that follow every disaster take advante of our morbidity, fear, and, laudable, desire to help those in need.

Or do these not fit into the category of con?

David Chess October 22, 2008 8:50 AM

I was also wondering where they got the first set of bulbs, and how long it would take for those $5 payments (minus the opportunity cost of all the walking and bulb-changing) to come to more than they would have made by just selling that first set to someone cheap.

Seems like a gedankenscam to me… 🙂

Roger October 23, 2008 6:14 AM

According to the westegg inflation calculator, $5 in 1975 is equivalent to about $19 last year (it hasn’t been updated for 2008 yet.)

If it took an hour per house (as someone wildly guesstimated), that it is quite a bit more than US minimum wage, but well under the US median wage.

Anyone who notices you going straight to the next house without getting a resupply out of a truck, is liable to figure it out and call the cops. If you do have a truck, well, they have a license number now, plus you have to subtract fuel etc from that paltry five bucks.

At any rate, a very poor return when you take into account the risk of getting caught.

Compare this to a guy who wrote a letter to the local rag recently, reminiscing about his first business venture when he was about 10 years old. He went to the discount markets and bought pencils for 1 penny each, cut them into quarters, and sharpened the pieces. Then he went to a major race track and sold them to punters who had forgotten to bring a pencil — at threepence each, and they sold like hot cakes. Despite the 1100% mark-up, his customers were very happy, because he was providing them with a service that at that point was more valuable to them than threepence.

I’ve said it before, and I’ll say it again: a conman is a just a bad businessman who doesn’t understand the importance of return custom.

caradoc October 23, 2008 11:47 AM

When I was a kid, my church youth group had regular ‘light bulb sales’ to raise money. We went door to door, asking one house to donate a light bulb and then asking the next one to buy it. The next day the neighbors compared notes and had a good laugh.

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