Finkel is a psychologist at Northwestern University and the author of the book "The All-or-Nothing Marriage," in which he explains why modern marriage is so hard and what couples can do to strengthen their own relationship.
In one section of the book, Finkel addresses the issue of compatibility - how to maintain it with our partner, even as we both grow and change. And I was left worriedly wondering: Is it possible that a couple can start out perfectly compatible, and then become less so over time?
Here's the answer he gave: "Even if we achieve compatibility in the marriage, there's no guarantee that that compatibility will remain strong over time."
Yikes.
Those few years that you're dating, before you get engaged, are what Finkel calls a "snapshot." He said, "How representative of your overall life are those two [or however many] years going to be?"
That's especially true, Finkel added, if those two years are when you're "in your late 20s, and you're building a career, and you're still hanging out some with your college friends, and you have some new friends.
"But there aren't screaming toddlers; there aren't newborns pooping their diapers all the time. So the degree to which you're compatible right now isn't any sort of guarantee whatsoever that you'll be compatible even in three years or five years."
Finkel's unsettling observations reminded me of something Susan Pease Gadoua, co-author of "The New I Do," told me in July: It's helpful to know you have an "out" of your marriage. That is, if one or both people grow out of the relationship, it might be upsetting, but it won't be shameful to leave.
The psychologist Daniel Gilbert's research on the "end-of-history illusion" is especially relevant here. Gilbert suggests that most people have no idea how much they'll change in the future - which means you can't predict whether you'll still want the same things from your marriage in 10, 20, or 30 years.
Ideally, both people in a relationship will grow and change in tandem. But realistically, that doesn't always happen. For sure, it's a scary prospect, but it's one that we're better off embracing.
The real question here is whether or not you and your partner are determined to make the marriage function anyway - and there's no right answer.
Finkel said:
"The ''til death do us part' vow is so interesting because it says, 'You know, I'm going to change. I know I'm going to change. We're going to take this gamble. We're going to make this promise that says, regardless of all those sorts of changes and even when all those sorts of changes might lead us in a different direction, we are going to work super hard to try to make sure this marriage works."