Read: How negativity can kill a relationship

Irrational anxieties and emotional repression can of course cause relationship problems, so it’s feasible that a few hours of reduced inhibitions and fears, paired with some gentle guidance from a therapist, might help some couples. The two psychiatrists found that some 90 percent of their clients benefited, and many of them reported that they “felt more love toward their partners and were better able to move beyond past pain and pointless grudges.”

Earp and Savulescu are careful to point out—at several points throughout their book—that drugs like these have shown promise in some settings, but require much more research before they should ever be considered viable mainstream treatment options. And if they ever reach that status, “Such drugs should never be taken in a vacuum, alone or with unprepared others, without the right mental or emotional groundwork, or with the expectation that they will induce improvements all on their own,” the authors write. “They won’t.”

Dominic Sisti, who teaches medical ethics and health policy at the University of Pennsylvania, notes a widely shared view among bioethicists: Certain drugs and pharmaceuticals can and should be used in therapy contexts. MDMA especially “can help reform the bonds that maybe were under stress, or broken through years of challenges or difficulties in a relationship. Or it can provide insight that maybe the relationship is over,” he told me. “Those are things that often take weeks, months, years of therapy to get to, but MDMA sort of catalyzes that.”

Sisti also agreed with Savulescu and Earp’s identification of “gray” marriages with kids as having the most to gain from chemical intervention. Still, he said that some in the bioethics field object to the “love drugs” idea—mainly due to religious or quasi-religious beliefs about love and marriage. “The most common argument [against it] is that you’re sullying something that’s divine,” he said, “that it’s a spark given by God, or preternatural in some way that we shouldn’t be screwing around with.”

Earp and Savulescu acknowledge the criticism, but they ask readers to consider romantic love the same way they might consider another one of life’s (smaller) pleasures: cake. Imagine the way it feels to eat the first bite of a delicious baked good, they write—and then, imagine that you helped bake it. “Does the cake taste any less delicious to you now? Does knowing the recipe, the chemical makeup of the various ingredients, somehow rob your tongue of the flavor it so craves?”

Indeed, the authors suggest that familiarity with something’s inner workings—how all the ingredients affect one another, how adjusting their ratios might help or hurt the end product—not only won’t spoil the magic, but might enhance it. And in the case of a relationship that has produced a family, that knowledge might just save it.

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