“There is always some madness in love,” Nietzsche wrote. “But there is also always some reason in madness.” It’s the latter half of that proposition that forms the subject of Berit Brogaard’s new book, On Romantic Love: Simple Truths about a Complex Emotion. Brogaard, a professor of philosophy at the University of Oslo and head of a synesthesia lab at the University of Miami, makes the case that love is an emotion subject to rational control: We can will ourselves to fall in or out of it. She draws on a host of psychological studies, philosophical theories, and personal stories to challenge the conventional wisdom that love is beyond our control.

Alice Robb: How can you fall out of love?

Berit Brogaard: You can use some of the same techniques that you use to change your other emotions. A lot is known about how to get rid of anxiety disorders, alcoholism, heroin addiction. Some of the same methods can be used to fall out of love.

When people are abusing heroin, they are more likely to overdose if they change their environment. If you normally go and shoot up at 10 a.m. on Tuesdays at a particular location, for example, and suddenly you do it on Saturday night at a different location, you might overdose even if you are taking exactly the same amount. The body learns when it can expect this toxin and it’s prepared to do something about it—to break it down, get rid of it. We know this from our own lives as well. If you normally have a drink or two with dinner, but suddenly you go to a wedding and they serve champagne in the morning, you feel a lot more drunk from that one glass than you do from two glasses of wine at dinner. If you want to quit a drug addiction, you would not want to be in an environment where the body is prepared with all its enzymes and chemicals, because that will trigger cravings.

So what does that have to do with falling out of love? To fall out of love, you would want to make as many changes as possible. If you used to get together with your girlfriend or boyfriend on Tuesday nights, the body might expect that to happen; you need to put yourself somewhere else. If you’re in the same environment, your body is going to have expectations for what used to happen.

There’s another approach, known as the Sinclair Method, which was developed to treat alcoholism. You take a drug that triggers the same receptors as alcohol does, but it doesn’t give you the same pleasure; now, when you drink alcohol, it doesn’t satisfy you to the same extent. I suggest that you can use a similar technique: You create a situation where the “drug”—the person you want to fall out of love with—is not going to affect you in the same way. You can try to teach your brain that the person isn’t that great. You can imagine your loved one in situations that are no good. If you do that for long enough, your brain may start to believe it.

Another way to fall out of love is to make your brain bored. This is a famous method for getting rid of phobias. If you go to a therapist and you’re afraid of spiders, say, you will be made to encounter spiders. You might be shown spiders on a computer first, and then you have to be in the same room as one, and then eventually you are exposed to it, and even touch it. Eventually, the brain becomes bored by this kind of stimulus, instead of producing fear in front of it. If your ex had a particular car—an Audi, for instance—you could go to the store and test-drive an Audi that was the same model as the one you used to drive in with your ex. That sounds like the opposite of what people would normally tell you: “Forget about your ex.” We can’t just forget about things. You don’t have to fight it off all the time, whenever you encounter reminders of your ex.

AR: What about the opposite—if you want to make yourself more in love, or make someone else fall in love with you? Does the New York Times’ “36 Questions That Lead to Love” have a scientific basis?

BB: What you are really doing, with asking personal questions and staring into each other’s eyes, is creating a feeling of intimacy. Intimacy can trigger the release of dopamine, which is a feel-good neurotransmitter, and the brain might be tricked into feeling that you’re in love.

Another thing that you can do is try to release another neurotransmitter, serotonin. Serotonin is sometimes called the feel-good hormone, but it’s actually more like a feel-safe-and-secure hormone. When your levels of serotonin are stable, you don't have anxiety and you feel good about yourself. When the levels drop, you can have anxiety and depression, but low levels of serotonin are also found in the early stages of falling in love. How do you generate that kind of brain cocktail? You expose the person in question to situations that would trigger a kind of fear or adrenaline high. The brain might confuse that with love. There’s a famous experiment where a woman was pretending to do a survey, and she surveyed some men on solid ground and some men on a seemingly dangerous bridge. After the survey, she gave them her phone number and told them to call if they had any follow-up questions. Most of the men on the bridge called her, whereas most of the men on solid ground did not. The speculative conclusion was that they developed a crush on her because the brain got tricked into thinking that this adrenaline high was a signal of being in love or having a crush.

AR: To go back for a moment to what you were saying about serotonin—do you agree with Helen Fisher’s argument that anti-depressants can diminish people’s ability to fall in love?

BB: I completely agree. When you take an anti-depressant, particularly one that targets serotonin, you risk stabilizing your serotonin levels to an extent that it’s very hard for your brain to get the serotonin levels to drop, which is what they do when you fall in love. But there are anti-depressants on the market that don’t target serotonin.

AR: You study people with synesthesia. Does their condition affect their experience of love and sex?

BB: Synesthesia is a mixing of the senses, and it comes in many varieties. People might see numbers and letters printed in black as having a color. There are some people with synesthesia who have very extreme experiences during sex. They might have color experiences or even sound or taste experiences. The color experiences are the most common.

There was a study done of people with this form of synesthesia. What they experience is almost a sexual trance, like a spiritual state but of a sexual nature. You would think this would be the most optimal sexual experience, but they found that, in most cases, they actually weren’t as satisfied as people without synesthesia. The researchers think that these people felt alone with their extreme experience. Previous research has shown that maximum sexual satisfaction requires more than just an intense sexual experience. It requires some kind of role enactment and partner engagement. It was partner engagement was missing in these cases.