All unhappy relationships are alike, says John Gottman. And they embody the fact that negative emotions, like defensiveness and contempt, have more power to hurt a relationship than positive emotions have to help a relationship.

The analogy to the seminal book by Sir Isaac Newton, The Mathematical Principles of Natural Philosophy, is hard to miss. What is your intention in doing so?

Yes, exactly. The reason for the title is that making physics mathematical enabled the field to make huge strides forward in understanding the dynamics of mechanical systems. It is ironic that Newton’s personal relationships were a total disaster. It is my hope that making the study of love relationships mathematical will also lead to a greater understanding of human love relationship dynamics. I think it, in fact, already accomplishes that.

 For a long time, you've been interested in the mathematics of relationships. What made you think that relationships could be expressed in mathematical terms?

Well, I started life as a mathematician. Our ability to predict the future of relationships is probably the most replicated set of findings in the family research literature. Now other labs have discovered similarly high levels of prediction. I had the dream that math modeling of these predictions would shed new light on understanding the predictions. And it has done that.

And what does doing so tell us about the nature of relationships?

I summarized what we have learned from the math as 45 new principles about love relationships. These new principles are based on just a few axioms about couples’ interaction, such as the axiom that negative affect triumphs over positive affect. That means that negative emotions, like defensiveness and contempt, have more power to hurt a relationship than positive emotions have to help a relationship. We have now demonstrated the truth of that assumption in some published work I can forward you. That assumption is the basis of the shape of the “Influence Functions” that describe the two interlocking “love equations.” An example of the insights we gain is that a matching shape of influence functions across partners underlying relationship success, while mismatches predict relationship failure. A totally unexpected result. Another example of an unexpected finding is that conflict avoiding couples have resilient relationships (not that they are without risks).

Can there really be principles that pertain to all relationships?

Yes, the international work we and others have done suggests that there are universal principles that hold across the planet for our species. These longitudinal predictors of relationship outcomes have generalized across sexual orientation and phase of life (we’ve studied couples across the entire life course).

In all cultures, or only in those with assortative mating?

I think that these principles will hold for arranged love relationships as well, even though these don’t go through our limerence phase. There still are successful and unsuccessful arranged relationships.

Was Tolstoy wrong in saying that each unhappy family is unhappy in its own way?

Yes, he was 180 degrees wrong. All unhappy relationships follow the Markov absorbing state that negative affect is easy to enter and hard to exit (in earlier work I called this the “Roach Hotel Model” of bad relationships: they check into negative affect but they don’t ever check out). Repair processes fail in those relationships, because the trust has eroded (in mathematical terms of game theory, the Nash equilibrium is unattainable). Happy couples have much more variability, in fact, and not as much rigidity. Pioneering family therapist Jay Haley also observed this fact in studying speaking patterns in normal families versus families with a schizophrenic child.

Why does marriage matter beyond love, and what evidence proves that?

The answer is that there is a third phase of love relationships (after the limerance phase and the trust phase) that involves commitment, which is really saying that “This is my life journey: This person is enough for me.” That stage includes cherishing one’s partner’s positive qualities and minimizing the negative. The late psychologist Caryl Rusbult’s brilliant three decades of work really established this on a strong empirical footing. I had the opportunity to combine her questionnaire with my observational and physiological measures to assess what commitment means empirically. The ceremony “we are married” appears to ritualize this commitment, which appears to be very important to people. 

Does knowing the 45 principles of love eliminate the romance everyone prizes?

Does understanding the way a star works eliminate the awe we feel when we look at the night sky? Or does the knowledge add to the majesty of the night?

To keep on the Newtonian path, does the nature of a relationship reflect the amount and kind of energy put into it?

Yes, exactly. That is true. However, in one of my chapters I review the history of physics that shows that the concept of “energy” was not a Newtonian concept. It did not come into physics until the 18th century, with the equations of Lagrange and Euler (which I also apply to relationships in this book). One theorem I prove in Principia Amoris is that without added energy, relationships will deteriorate. Everyone sort of knew that, but it’s cool to be able to prove it.

What are the most important principles for couples to know that they perhaps don’t now know?

I would say that it there is one most important thing to understand, and a corollary to that. That one thing is that it appears as if the motto of all successful relationships is, “Baby, when you’re hurting, the world stops and I listen.”  That motto builds trust and maintains friendship over time. The corollary is that repair is the sine qua non of relationships. We all mess up communication, and I can prove that is par for the course. We are only successful at repairs being accepted by our partner because we have established and maintained friendship and trust. 

Do the best relationships require the same inputs and actions of both men and women?

No. In heterosexual relationships it is an established fact that women tend to bring up 80 percent of relationship issues. The challenge for women is softening the startup of these discussions by accepting responsibility for at least part of the problem. For men the challenge is twofold: (1) Turning toward a women’s bid for connection a high percentage of the time, and (2) Maintaining a sense of we-ness in the relationship.

What was the most surprising thing you discovered in researching/writing this book?

After about 15 years of this mathematical work, I suppose that I am most surprised and delighted by the simplicity and elegance of our findings. With just a few parameters we get nonlinear differential equations that can describe any relationship. I think that’s amazing. That means we can precisely assess the strengths of a relationship and the areas that need improvement, and we can help couples make these changes. It really is a science! 

This mathematical work has been reported in peer-reviewed journals and a monograph (“The mathematics of marriage,” M.I.T. Press, 2002), but it has been almost totally ignored by the academic world of relationship research. I think that’s mainly because the math is too challenging for most psychologists. I found that very disappointing. It adds so much. I expected that the success of this work would have generated more interest among relationship researchers than it has.

Only Paul Peluso has taken it (in collaboration with me) and applied the same math to study individual psychotherapy, with great success. That work is now being accepted by psychotherapy journals, which is very rewarding. 

What is the most important point you want to get across?

The most important point is that this field is no longer “soft,” but has become a real science. 

Who is the book intended for and who would most benefit by reading it?

I wrote this book for therapists. I believe that the math gives us a new language for describing and understanding relationships with a new precision, and I want therapists to be able to think with that new language. It is quite powerful, and I believe that it can help therapists be much more effective.  

If you had one piece of advice about relationships, what would it be and for whom?

We know from the structure and function of the brain that we mostly rely on procedural memory to get us through our day. These memories reside in the basal ganglia. These are our well-established habits, our memories of how we do things, like brush our teeth and drive our car. I believe that the new functional ways of communicating in a love relationship (like the Gottman-Rapoport Blueprint) have to become automatic habits like those. So when our partner says, “I am so angry with you right now!” the automatic response will become, “Okay, baby, talk to me. I’m listening.” So, my advice is: Learn all these new ways of relating, and make them habits. Actively build friendship and intimacy; turn toward bids for connection; express appreciation, respect, and affection often; deal with conflict constructively; honor your partner’s dreams; and build shared meaning. Imbue these with “daily-ness” and love will thrive.

I also want to convey to couple therapists how important it is to measure physiology in treatment. When people are flooded physiologically, they can’t listen or empathize. No therapist can tell that a person’s heart rate has exceeded the heart’s intrinsic rhythm, which is when we start secreting adrenaline and getting flooded. Couples’ therapists need to learn more about biology and use that knowledge in therapy.

What would you like to see happen as a result of this book?

Well I would love it if people would say, “Hey this math is cool. Even if I can’t follow the equations, I can really understand the visual graphics. I get the concepts. Now I have a new understanding of love relationships I never had before. I feel more empowered at being able to understand and help my clients, and even improve my own relationships.”

About THE AUTHOR SPEAKS: Selected authors, in their own words, reveal the story behind the story. Authors are featured thanks to promotional placement by their publishing houses.

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