Against the Promise Keepers: On the Contract Theory of Infidelity

Just before Christmas in 2011, an Italian man named Antonio was looking through an old chest of drawers, and found a series of letters his wife Rosa had exchanged with her lover. He confronted her, she confessed, and he filed for divorce. This sort of thing, unfortunately, happens every day. What makes this case unusual is that the couple were both ninety-nine years old. They had been married for seventy-seven years. The affair took place in the 1940s. As this case shows, infidelity is a difficult thing to forgive.

If you found out your partner had cheated on you, would you be upset? I’m guessing the answer is yes. So why do you think you would you be angry? Let me try to guess . . . Because they made a promise to be faithful, and they broke their promise. And because they lied to you. A healthy relationship is based on trust, and it can’t survive without it. Dr Simon Longstaff of the St James Ethics Centre in Australia insists that the pain of infidelity results from broken trust rather than any particular physical act. “It comes down to a question of promise keeping,” he says.

Now let me tell you another story. (It’s true.) A man in Britain made a pact with his wife. They were both trying to lose weight, so they each pledged they would give up their favourite cookies so long as the other did the same. But he cheated. He continued to buy the cookies he loved, and ate them secretely, in the car outside the grocery store. However, one of the cookie packages had a contest for a free trip for two to the Bahamas, and he couldn’t resist entering. And he won. The company called his house to tell him the good news, and his wife answered. So they told her instead. And so she learned the whole truth.

He broke his promise, and he lied about it, just like the wife of the ninety-nine-year-old Italian man did. But in this case, she forgave him. The couple went on the trip together.

Now maybe some of you wouldn’t have been so forgiving. Because he had broken his promise and deceived you, you would have left him then and there. But I’m guessing most of you would have laughed it off, indeed probably even have been happy about it all because you came out ahead, with a free trip. And, if it happened to a friend, you’d think it was a bit odd if she did end an otherwise-happy marriage over an incident like that. The fact is, people break promises in relationships all the time. They pledge that they will work less hard and travel less, and then suddenly they get offered a a promotion and they accept it, even though it means longer hours and more travel. They also tell lies to their partner – about how much money they spent on their new golf clubs, for instance. These sorts of things may cause arguments, but they generally do much less damage than cheating does. Infidelity is the leading reason why couples separate. As the case of Antonio and Rosa shows, the sense of betrayal can be hard to overcome even after decades have passed. Even when the relationship survives, it is usually at the cost of much pain.

I’d like to make a bold suggestion. Whatever they may claim, what upsets most people about infidelity isn’t the broken promises or the lying. It’s the sex. In our society, we expect a sexual monopoly over our partner’s bodies, as the precondition for a lasting relationship. That’s a cold way of putting it. But I think it’s accurate, and I am somewhat puzzled why so many people seem to convince themselves of what we might call the contract theory of fidelity. On this theory, we should be faithful because we promised to be. But the contract theory can’t explain why sexual infidelity causes more pain than other forms of promise-breaking. And it presumes that the contract itself makes sense. Imagine we have a friend who loves classical music. He begins dating someone who is also passionate about it. Now imagine he declares to us that he has stopped listening to classical music since he has been in the relationship. When we ask why, he tells us that because his partner loves music as much as he does, they have agreed that each of them would stop listening so long as the other does. Such a pact would seem utterly insane.

I am not arguing that infidelity is no big deal. But I do think that we need some better account of the harm it causes than the contract one provides.

Note: I heard the story of the British couple and their cookies years ago on the CBC programme As It Happens, and now I am unable to find any specifics about it. If anyone has any more details, please let me know.

Image: Jan Massys, David and Bathsheba (1562)

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  1. arthur schafer

    To summarize your theory, Neil, “It’s the sex, stupid”. This may be true for many/most men but I suspect it’s not true for most women. Ask some women this question: “You discover that your husband/partner has had a one-night-stand while out-of-town on a business trip”. How upset are you (on a scale of 1-10). Then, ask the same women this second question: “You discover that your husband/partner has a female friend at work with whom he shares intimate problems and feelings, problems and feelings which he does not share with you or, alternatively, which he also shares with you.” How upset are you (on a scale of 1-10).

    I want to offer you a wager. I’ll wager that most women would be more upset by either of the second two alternatives, both of which involve sharing intimacy with another woman, than they would be with one instance of casual sex.

    If I’m right about this then, for women at least, it’s not so much the sex as the intimacy. It would be easier to forgive sexual infidelity than emotional promiscuity or non-exclusivity. I concede that men are more likely to be upset by sexual infidelity or find it more threatening than emotional infidelity.

    Posted February 11, 2012 at 4:29 pm | Permalink | Reply
  2. Leaf

    @arthur schafer – I have heard this argument before, but even though there may be different levels of reaction to different types of infidelity, it doesn’t change the fact that both can be treated as betrayal and both can hurt, whether male or female. We can put it anywhere on a scale, but the scale is still measuring the same thing.

    I think the most important point here is that our view of both sexual and emotional infidelity is skewed, and that not breaking trust should be what’s important to us. Beyond that, we can negotiate any sort of relationship rules we want. No two relationships will ever be the same in every way.

    Posted February 11, 2012 at 9:51 pm | Permalink | Reply
  3. neil

    Leaf, your comment implies that the man who secretely ate the cookies really is committing an infidelity, on par with sleeping with someone else. He broke trust when he snuck off to the grocery store. I think that is a perfectly rational, consistent view, but it does not seem to fit with the intuitions most of us have about the case. (I take it that’s what you mean when you say that our view of infidelity is skewed.) I was pointing out that there is a possible divergence between our intuitions and our beliefs — we believe that the harm is from promise-breaking, but we intuit that the harm is from the sex. You seem to be suggesting we should ditch the intuition and try to go all-in on the contract theory. That is certainly one solution.

    Arthur, I think you and I disagree about the data, or at least in our hypotheses about it since we have no actual data, but agree on the basic principle — that the contract theory on its own is insufficient. We agree there is a harm beyond promise-breaking. That was all I was trying to establish here. As a matter of hypothesis, I don’t think the gender variations will be especially large, nor very important, since I believe that most people are harmed by infidelity because of the close connection they tend to form, or worry that their partners tend to form, as a result of sex. In any case the two crucial questions remain unanswered. First, why do we think sex and intimacy are so closely tied together? Is there a natural connection, or merely a cultural one, and would we be better off trying to disentangle the two? Second, why do we want emotional monogamy — what is the harm in allowing our partner to form intimate connections with people besides ourselves?

    Posted February 12, 2012 at 10:22 pm | Permalink | Reply
  4. Leaf

    I wouldn’t say that it’s on par, obviously eating a cookie and sleeping with someone carry different weight. I just think a certain number of cookies can add up to the same weight over time, and we should be aware that small acts of deception can be causing damage even while forgiven at the time they happened. I agree our intuitions and beliefs definitely don’t match, but then I don’t believe we interpret our intuitions correctly much of the time, similar to how a child will react to a situation physically but can’t articulate beyond “I don’t know” or some indirect reply. Every year piles of new books come out to explain why we do things, because we never quite sure. Of course, we shouldn’t dismiss them entirely since they carry a lot of emotional value to people, but I think we’re better off when we’re open to discussing what the source is. I suppose what I’m thinking is that we base our relationships on contract but be sympathetic to intuition, then revise the contract based on that. Since a contract can’t cover every situation, we’re forced to bring in intuition, and that just makes a mess of things…and now I’m just rambling…

    Posted February 13, 2012 at 10:01 pm | Permalink | Reply
  5. Joel

    Sex can be seen as a symbol for intimacy, an act that says “i am yours, and nobody else’s”, which is a defining characteristic of a marriage. Marriage holds the emotional weight because it is makes a person’s life what it is; some people say their partner completes themselves (or some other vague poetic-sounding statement). Thus, even if the symbol was arbitrary, it would not be unjustified that people feel that way when they are cheated on. If agreeing to the sharing of the same cookie-diet was conventionally seen as a gesture of intimacy and a defining symbol of marriage in our culture, it would likely have a similar effect.
    But it isn’t arbitrary. Physical intimacy is an essential element to marriage; some would say a defining characteristic, and sex brings this to a maximum. Otherwise it would be little more than a friendship with economic benefits. The reason that physical intimacy is key to a good marriage, and why we consider it right for couples to have a monopoly over each other’s sex lives, seems to be benefits for evolutionary fitness, thus both cultural and natural.

    Posted February 16, 2012 at 11:15 pm | Permalink | Reply
    • Leaf

      You might enjoy reading Sex At Dawn for a strong argument against evolutionary monogamy.

      Posted February 18, 2012 at 12:49 am | Permalink | Reply
  6. I think there’s a lot to the contract theory and that the breaking of trust does account for a large proportion (but definitey not all) of the pain of infidelity for many people. But it’s just that this *particular* contract many people regard as an extremely important one, and that’s because of, yes, their strong feelings about sex and fidelity. Hence the breaking of this contract and the lying -together with the thought of the act itself – is more upsetting than the breaking of other less subjectively important promises. I guess my point is that I don’t see “it’s the sex stupid” and the “contract theory” as all that incompatible.
    I can also speak from my experience as someone who finds monogamy to be odd and impracticable, and who has been in a non-monogamous long term relationship for 7 years. If my partner had done the sexual things he’s done with other women and we *hadn’t* discussed and agreed on openness beforehand, finding out about it would have devastated me and without a doubt I would have ended the relationship – evidence for the contract theory. At the same time, while I don’t judge him for his extra-relationship exploits because we have an agreement, I have nonetheless, on rare occasions, felt sick with jealousy, hurt and insecurity despite our agreement – evidence for the “it’s the sex stupid” theory. Hence I am quite sure that, for me at least, it’s a combination.

    Posted March 1, 2012 at 2:41 am | Permalink | Reply

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