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CONTRIBUTOR / J. Keith Murnighan


Breaches in trust that happen early in a relationship can be devastating, but breaches that happen later in a relationship can often be overcome. The rational model assumes that people will do what most benefits themselves, but often, the process of building trust is driven by a small initial cue, such as a familiar name, that causes us to trust another person without much evidence. Ultimately, you are making yourself vulnerable by trusting another, and the rational model advises to proceed with caution.


We were interested in the long-term development of a relationship. And I’m an old fan of Hollywood movies, in particular, romantic comedies. So, Rosalind Russell and Cary Grant and His Girl Friday and a bunch of these movies.

When you watch them, it’s very easy to see that when there’s discord between the two stars early on, romance later is going to be supreme and fantastic.

One of the theories that we had was that if things are bad early, they may have a higher potential later on. Now, there’s an alternative way to think about it, of course — if things are bad early, they just don’t have a chance and they don’t go anywhere.

So, we actually tried to test the two, and we had interactions between people where there was a trust breach early or a trust breach after many cooperative choices.

And it turned out that the early trust breaches were devastating and led to less future cooperation, less trust.

When we saw breaches late, we thought that this might really, really damage things. It does immediately; it’s a shock when somebody breaches trust.

But our guess — and all we have is a guess at this point because we haven’t studied it enough — is that when someone breaches trust, they exhibit strength. And what happens with strength is we do respect it.

And when someone is trustworthy and strong — i.e., someone who’s trustworthy who doesn’t have to be — we tend to trust them more.

BUMPER: Overcoming a Breach in Trust

One of the things that should happen any time trust is broken is you should pursue and try and find out what happened, simply asking questions, because it can be the result of miscommunication, misunderstandings, a variety of things that are simple explanations that have nothing to do with a person’s trustworthiness.

However, if it was intentional, it tells you a lot about the person. And in business situations, what we find when there’s a serious trust breach, trust is gone, when it really comes to the crunch.

You might work with the other person; you might cooperate with them; you might have a beneficial relationship. But if you have to really trust them, it’s unlikely to happen.

BUMPER: Using the Rational Model to Decide Whom to Trust

The rational model suggests what rational people will do to benefit the most themselves. However, we’re not all completely rational, and we actually use very subtle cues and a lot of information to determine whether someone is trustworthy.

So, if you hire a lawyer, hopefully you’ve done some homework and you found out about that lawyer’s reputation, and that allows the trust process to develop more quickly.

Any time you trust someone, you’re vulnerable. You take the first step in whatever it is — sharing a secret, providing some information about a work project, or loaning money or a car. Any time you trust someone, you’re vulnerable.

The question is, how vulnerable do you want to make yourself?

The model tells you to be very cautious. And if you continuously get positive information, trust can continue to grow — again, to a limit.

At some point, things will level off because you don’t want to trust one person too much. It’s the old saying, “Too many eggs in one basket,” for instance.

In business situations, it truly pays to have many people you can trust a moderate to high amount and nobody you have to depend upon too much.

BUMPER: How Much Vulnerability? It Depends

How much do I actually want to loan my best friend? I’d be happy to loan him 5,000 dollars, 10,000 dollars. But when it starts to hurt me, can hurt me badly, do I really want to loan them 100,000 dollars? That would be tough.

In my classes, I often ask people, “Would you loan me 10 dollars?” And if they say yes, I say, “Would you loan me 20? Would you loan me 100?” There’s always a limit.

One time, I did ask someone if they’d loan me 10, and they said, “No.” I said, “How about 5?” They said, “No.” I said, “How about 2?” They said, “No.” I said, “How about 1?” They said, “Maybe.” That was a very cautious person.

Most of us are willing, with people we know, to take some risks. But there’s always a limit.