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I present to you, dear readers, the third and final part of a three part series based on the writings of Dan Ariely, the James B. Duke Professor of Psychology and Behavioral Economics at Duke University and a founding member of the Center for Advanced Hindsight.

Prof. Ariely’s work in decision making and behavioral economics focuses on how people predictably and repeatedly make the wrong decisions in many aspects of their lives. He is the author of three highly recommended books on the subject, each one a best seller in its own right.

These three posts each address a specific topic in male-female relations, each through the lens of “predictable irrationality”. Prof. Ariely graciously agreed to help with these posts, and his insights are incorporated throughout.

Part 1 (Why do men date “Bimbos”?) can be found here

Part 2 (Why are women attracted to unavailable men?) can be found here

Part 3 – Infidelity

An interesting thing happened recently: David Petraeus, one of the most decorated and celebrated military officers of recent history, formerly resigned from his position as Director of the CIA on the 9th. He cited “personal reasons”, but the story quickly leaked that Petraeus, who is married with two kids, was carrying on an affair with a colleague, who is also married with two kids.

Petraeus was a superstar. He was lauded and exalted in all the relevant magazines in the Western World as one of the most effective and influential leaders of our time. He was short listed as a possible Presidential Candidate in the near future. So why would Petraeus risk it all for some booty on the side?

But first some background on infidelity. It happens a lot more than people are comfortable admitting. Statistics are hard to come by because nobody wants to self-report that they are cheating, but most robust studies state that infidelity in marriage occurs 30% of the time, and in “non-married committed relationships” about 40% of the time. Because of the self-reporting bias, I think the actual numbers are sadly higher, probably 40% for married, and 50% for the non-married.

There are other nuances to infidelity as well. It occurs more frequently in those over 60 (!!!), and second most frequently in those under 40. Other factors, like if one spouse travels a lot, if the couple has children, or if both partners have similar educational backgrounds, also affect infidelity rates. Finally, most psychologists believe that women understate their levels of philandering more than men (!!!).

Let’s go back to our friend Petraeus. He’s at the top of his game and he knew all along that it would be a public catastrophe if he was caught or outed. Yet he kept the affair going, and the longer he kept it going, the riskier it became. Something about this seems completely irrational.

There are plenty of reasons why someone chooses to “step out”, but I am going to limit our discussion to the insights from Prof. Ariely’s work on the subject. In other words, we will take a deeper dive into the behavioral aspects of infidelity in men (but also in women).

A few years ago, Ariely and his colleagues published a paper called “The Heat of the Moment: The Effect of Sexual Arousal on Decision Making”. The paper examines men’s ability to make logical decisions when they are “turned on.” You can read for yourself exactly how he convinced a bunch of single guys to answer questions while being aroused, but the findings are pretty conclusive:

“The increase in motivation to have sex produced by sexual arousal seems to decrease the relative importance of other considerations such as behaving ethically toward a potential sexual partner or protecting oneself against unwanted pregnancy or sexually transmitted disease.

Sexual arousal seems to narrow the focus of motivation, creating a kind of tunnel-vision where goals other than sexual fulfillment become eclipsed by the motivation to have sex.”

In other words, Prof. Ariely shows that the “Heat of the Moment” actually exists in reality. For Petraeus, the heat of his Moment overpowered his sense of guilt, ethics, and civic responsibility.

But all of this just leads to a much more interesting question: Why would someone in Petraeus’ position put himself into a position where a “Moment” might occur? Again this seems like irrational behavior.

To answer this, we turn to a different paper by Ariely called “The Dishonesty of Honest People: A Theory of Self-Concept Maintenance”. Ariely and his colleagues tested various hypotheses about why people who are usually upright citizens (or rather, who deem themselves upright citizens), would engage in illicit behavior. The paper is quite complex, so I will summarize the key findings:

“The results show that (1) given the opportunity, people will engage in dishonest behaviors; (2) increasing attention to internal honesty standards decreases the tendency for dishonesty; (3) allowing more flexible categorization increases the tendency for dishonesty; (4) the magnitude of dishonesty is largely insensitive to either the expected external benefits or costs associated with dishonest acts; and (5) people know that their actions are dishonest but do not update their self-concepts.

People who think very highly of themselves in terms of honesty make use of various mechanisms that allow them to engage in some level of dishonest behavior while retaining their positive view of themselves.

… The level of dishonesty dropped when people paid more attention to honesty-standards but climbed when they had more wiggle room for a categorization that was more compatible with an honest self-concept.”

What does this mean?

It means that people generally think of themselves as honest and loyal, but small steps and rationalization can create a slippery slope that leads to infidelity.

Our friend Petraeus can further explain. His mistress was writing a biography on him, so they were spending a lot of time together; chatting, jogging, going to dinners, etc. In all of these instances, Petraeus was categorizing the time he spent with the woman as “research for her book”, which allows him to rationalize their proximity. He was putting himself closer and closer to the “Heat of the Moment”, while at the same time justifying his reason for being there.

Furthermore, Petraeus probably convinced himself that his affair was defensible because he was away on military missions for long periods of time, and he probably thought to himself: If everybody else is doing it, then it’s ok for me as well. This is what the article refers to as a “mechanism” that allows the person to still maintain an image of themselves as honest and loyal, while creating a grey area where dishonest behavior is OK.

The important part for you, dear reader, to take from this is twofold. First, if you are someone who sees infidelity as a black-or-white deal breaker, then you should probably look carefully at the lifestyle of your potential guy. Is he always on business trips? Is he frequently intoxicated at office parties where you are not around? These are all grey areas where categorization and rationalization could possibly lead to “Heat of the Moment” scenarios.

Secondly, is he someone who is loose with his moral compass? If half of your Econ class is cheating on the exam, will he do it as well, or will he at least think twice about it? In other words, will he quickly create a moral “mechanisms” that allow him to be dishonest just because others are doing it?

I’m not saying that everybody cheats. I’m also not saying that your potential guy is destined to be a cheater just because he’s frequently away on business trips and his office 90% female. What I am saying is that we should all be aware that certain scenarios may create a “Heat of the Moment”, and if you don’t trust yourself, or if you don’t trust your partner, maybe it is best to avoid potential moments in the first place, or at least create an environment where your moral compass is strong enough to resist such urges.


(דן – תודה על כל האזרה!)