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Marriage hack - changing utility functions

Hello Friends and Family!

I want to share an interesting insight Lihong Lu McPhail and I had last night about marriage. In short, when we view our preferences as flexible we are more likely to view compromise as an opportunity for self-improvement instead of a power struggle. Marriage provides a tool for changing our ”utility functions” in ways that help to align each partner's incentives. Your thoughts are appreciated.


We just finished writing up a summary of one of our favorite books on relationships, “Seven Principles for Making Marriage Work” by John Gottman. If you haven’t heard of Dr Gottman then I strongly recommend checking him out.

Unlike most every other “expert” on marriage, Gottman has been able to accurately forecast if a couple will stay together with 91% accuracy. He accomplished this by monitoring couples in his “Love Lab”...cataloging and measuring non-verbal signs of contempt, degree of eye contact, heart rate, and hundreds of other pieces of data. His approach makes it hard to argue with his conclusions.

After going through all this material again I was still left with an unanswered question.

Why do marriages fail?

Yes, it is unlikely that we uncovered anything earth shattering on such a well researched topic...but with over half of marriages still failing it seems to still be an open question.

Gottman is able to predict which will fail, but he doesn’t say why. For example, he argues that of the “Four Horsemen of the Marriage Apocalypse” that signs of “Criticism” (which he defines in detail including how it is distinguished from complaining) is the single most powerful predictor of divorce. But he doesn’t explain why some couples fall into a pattern of criticism.

Here is the cause to the best I can figure...summed up in another question:

Do both sides of the relationship believe that their utility functions are flexible?

If yes...the relationship is more likely to succeed. If no...the relationship is more likely to fail.

A utility function is simply the equation that decides how happy you are. It has lots of factors, like whether you are hungry, like your job, are sick...etc.

Economists tend to believe that the preferences implicit in our utility function are fixed. For example, if you value work over family today, then you will value work over family tomorrow. If you hate washing dishes today you will always hate it. But this assumption seems to be as bad for marriages as it is at predicting future economic growth.

When we believe our utility functions are fixed there is only one path to happiness...getting more. Increasing all the things that you think make you happy and decreasing all the things that make you sad.

Lets use a simple example of a recently married man, whom we will call Joe, that loves video games. In fact...all he cares about are video games.

Utility = Video Games x Beta

Beta is a muliplier which translates each hour of video games into ten utility (10x😃) points. If Joe believes that this is his utility function then all he is going to want to do is play ... 24 hours a day for a total of 24 * 10 = 240 😃.

Now, suppose his wife, lets call her Lulu, wants Joe to spend just one hour a day cleaning up the giant mess he creates in the basement trying to eat (and other things) while simultaneously shooting up fictitious bad guys.


This theoretically poses a problem for Joe because any compromise would require a reduction in his overall utility.

But reality doesn’t work that way. Another word for this drive to consume is the hedonic treadmill ... treadmill because it is never ending. We can always have more, and will always want more because we will always habituate to however much more we get.

So what are we to do?

Change your Beta coefficients!

Instead of trying to maximize every input that has a positive Beta Coefficient...decide which coefficients you wish were bigger (or smaller), and make a conscious effort to make them bigger (or smaller).

Marriage seems ideally suited to this purpose. When you live alone you don’t have to compromise. You can just pursue whatever you want as long as you want forever. But marriages require compromise:

  • When we compromise we often realize that the things we thought were really important (large Betas) turn out to be not as important as we thought.

  • When we care for someone else our Utility Function starts to become a blend of our partners.

  • When we think deeply about our mortality and how we want to be remembered, we are more willing to change what we value (change Beta Coefficients).

  • When seen through this light...arguments become opportunities. “Winning” an argument doesn’t really make sense anymore. “Getting your way” is no longer the core objective.

Compromise only requires losing when partners believe that they need to give something up that they need to be happy. Allowing for change makes it possible for both sides to actually find greater happiness than their earlier “optimized” inputs imply.


At the end of the day it seems that the best marriages are one in which both partners decide to think in terms of “We” instead of “Me”. It requires the flexibility to let go of the petty and narrow in exchange for the mutually beneficial. That’s hard to do, but recognizing positive change in our preferences (utility functions) as a good thing is a great first step.


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