[Originally published February 5, 2013.]

- - -

Susan, we need to talk. I’ve been doing a lot of thinking lately. About us. I really like you, but ever since we met in that econ class in college I knew there was something missing from how I felt: quantitative reasoning. We can say we love each other all we want, but I just can’t trust it without the data. And after performing an in-depth cost-benefit analysis of our relationship, I just don’t think this is working out.

Please know that this decision was not rash. In fact, it was anything but—it was completely devoid of emotion. I just made a series of quantitative calculations, culled from available OECD data on comparable families and conservative estimates of future likelihoods. I then assigned weights to various “feelings” based on importance, as judged by the relevant scholarly literature. From this, it was easy to determine that given all of the options available, the winning decision on both cost-effectiveness and comparative-effectiveness grounds was to see other people.

It’s not you, it’s me. Well, it’s not me either: it’s just common sense, given the nature of my utility function.

The calculations are fairly simple. At this point in my life, the opportunity cost of hanging out with you is fairly high. Sex with you grants me seventeen utils of pleasure, but I derive negative utils from all of the cuddling afterwards and the excessive number of buttons on your blouse that makes it very difficult to maneuver in the heat of the moment. I also lose utils when you do that weird thing with your hands that you think is affectionate but feels almost like you’re scratching me. Overall, I derive thirteen utils of pleasure on a typical Friday night with you, or fourteen if we watch The Daily Show as part of it (fifteen if they have a good guest on the show).

Meanwhile, I could be doing plenty of other things instead of spending time with you. For example, I could be drinking at the Irishman with a bunch of friends from work. I derive between 20 and 28 utils from hitting on drunk slutty girls at the bar. Since Jeff always buys most of the drinks anyways, the upfront pecuniary costs are low, and I have no potential negatives in terms of emotional investment. However, most of those girls don’t laugh at my jokes, which drives down utils gained. Thus, I could get between 14 and 21 utils from a night out at the bar.

If you’re looking for the kind of guy who’s interested in maximizing the worst-off outcome regardless of potential gains—well, I’m not that guy. All you have to do is look at the probabilities and compare the feasible range of outcomes in terms of number of units of pleasure to see that we’re going to have to call this relationship quits.

This may feel cold, but there’s nothing cold about well-reasoned analysis.

Like all humans, I know I am fallible—and since I have a natural tendency to improperly discount the future, I have made sure to accurately determine present future value of costs and benefits. But even considering the diminishing marginal returns of hitting on the aforementioned drunk slutty girls, the numbers simply do not want us to be together.

I know this breakup might come as a bit of a shock to you, which I have also factored in. The disappointed look on your face costs me 5 utils of pleasure, but the knowledge that this is the right decision in the long-term makes up for that. Additionally, I have included in my calculations the fact that as a courtesy I will have to pay for this dinner in its entirety, which, given the gender parity we have previously expressed in our relationship, would normally cost me only half that.

I want you to know that this decision isn’t just for me—it’s for you, too. I’ve done the calculations. There are plenty of eligible bachelors out there who are probably able to more vigorously, consistently, and knowledgeably have sexual intercourse with you. While the thought of you being with someone else causes me a substantial negative utility that makes me feel as though I am going to vomit, I know that in the aggregate everyone is better off, and therefore it is the right decision for us to make.

There’s no need to try to persuade me otherwise, Susan. We just can’t let our feelings get in the way of the math.

In the meantime, I need to get back home. My utility calculations tell me that the best thing I can do right now is strip down to my boxers, microwave a quesadilla, and watch a bunch of episodes of The Wire. It might seem strange and horribly unproductive, but it’s not me—it’s just my utility function.