Carl Sagan, in his excellent book, A demon-haunted world: Science as a candle in the dark, advises us to develop a finely honed baloney detector. It’s the sort of device that will help you avoid false claims, con artists, and snake-oil salespeople.

In times gone by, snake-oil salespeople actually sold various potions and lotions that claimed to cure just about everything. Of course, some still do if you look at their posters underneath highway overpasses! Nowadays, snake-oil purveyors who operate in business have become far more sophisticated. They often come in the guise of a business guru, turnaround expert, or futurist.

They will promise lucrative returns combined with unrealistic guarantees — if only you hand over some hard-earned savings. They will try to strong-arm you into signing medieval-like contracts while claiming that it is your only salvation, or they’ll try to persuade you that they, and no one else, have the answers to all the questions you’ve been struggling with.

Please don’t be fooled. Cultivate your baloney detector.

Here are five warning signs to look out for when dealing with possible con artists:

1. They want you to feel special and carefully selected.

Imagine that you pop down to your local supermarket to buy some bread. As you’re standing there, thinking about whether to go for full-grain or white, a shop assistant approaches you and gives you a long questionnaire to fill in. She explains that her shop doesn’t sell bread to just anybody. Only the selected few, the ones who answer the questionnaire correctly, are allowed to buy their bread and milk here.

Crazy? Absolutely. But not uncommon in the world of selling snake-oil.

Con artists know that if they can make their victims feel special, cleverer than those around them, more select, they can sell almost anything to them, at any price. There’s a complex psychological dynamic at work here: the more hoops people have to jump through to get at a reward, the more passionate they will be in defending that reward as valuable, even when it isn’t valuable in the slightest.

So beware of businesses and gurus who would have you jump through hoops, meet multiple criteria, or prove your own worth before they’re willing to do business with you.

2. Their private identity and documents (e.g. contracts) are at odds with their public image

Snake-oil salespeople are careful to cultivate positive public identities. They want to be seen as benevolent, fighting the good fight, of having the interests of the little man at heart. There’s of course nothing wrong with these desires per se. But in the interest of proper baloney detection, one should check if a guru’s public identity matches his or her private one.

Sooner or later in business you will be handed a contract of some kind. For many con artists, the contract represents the final step in a carefully orchestrated process with the sole goal of getting you to sign on the dotted line when you really shouldn’t.

Therefore, check documents such as contracts very carefully. Consult an attorney. Research the guru or business to see if there have been complaints, legal action, and similar incidents marring their lifespan.

Look out for contradictions between public and private images. If the guru has a public image of being benevolent and interested in helping all who are in need, but his or her contract seems to hark back to the days of indentured servitude, there’s probably something amiss.

Should you take investment advice from someone who says they are trustworthy but who has been investigated for fraud? Should you sign a contract that has severe penalties and few safe ways of getting out without incurring massive costs? Probably not.

3. They are masters of self-publicized competence

There’s an old saying: if it seems too good to be true, it probably is. A companion to that piece of wisdom should be: if someone says they’re great at something, they probably aren’t.

People who have mastered a skill or are very good at something often feel personal doubt at their competence. It’s because they know enough about their discipline to know what they don’t know. This often drives them forward and motivates them to become even better.

Snake-oil salespeople behave quite differently. They seek out the limelight, they love boasting and publicizing their own competence to anybody who’s willing to listen. They are so confident and devoid of self-doubt that the media falls in love with them time and time again. The consequent fame becomes a shortcut into people’s hearts (and pocketbooks).

Beware of overconfidence and absolute certainty. No matter how good someone is, if they are honest and authentic, they will have to acknowledge that there’s always a faster gun in the West. There’s always someone who may have a better way or a more elegant solution.

Don’t let fame (or confidence) fool you. In today’s world, fame is incredibly fleeting and incredibly easy to obtain. It is not proof of competence or integrity. It never was.

4. They generate polarized opinions

Only the terribly naïve live in world without nuance, where things are black or white. Real people who live in the real world know that things are generally more complex. There is a spectrum along which many matters fall.

So it is curious when you encounter someone or something that attracts highly polarized opinions. People seem to either adore or hate them. Their supporters defend them with overdriven praise and religious-like fervor. Their detractors threaten legal action and lose emotional control.

If you’re honing your baloney-detector properly, you should be wary around businesses and people who generate this sort of reaction.

Snake-oil salespeople will have a core, almost cult-like following that they’ve groomed over time to ensure that they can continue to sell their brand of baloney to the rest of us.

But they would also have made enemies. People who have been burnt or who have seen beneath the public façade. It’s probably a good idea to look carefully at what these folks have to say.

And remember, true competence has a way of shining through. Truly competent people and businesses will have real evidence to back up their claims.

Thank you for reading this post. At Omnicor, we use the principles of science to help our clients make the best decisions given the available evidenceWe don’t have all the answers. We have doubts. We know there’s always a faster gun out there somewhere.

If you want help with your organization or talent problems — help that isn’t just snake-oil — contact us for more information.