It is common to have erotic fantasies about co-workers, strangers, and good old figments-of-our-imagination. While children have imaginary friends, adults often benefit from having imaginary lovers. But many people are so threatened by their partner’s freedom to desire and fantasize about other people that they forbid them to socialize with those of the opposite .

This insistence on strict of fantasies and desire stems from the common misconception that if we allow our partners to fantasize about, communicate with, or with others, they will inevitably act on their . of infidelity is relentlessly stoked by media reports: All sorts of celebrities seem to be their partners! In fact, the hit parade of famous infidelities includes numerous statesmen of different political stripes and : Schwarzenegger and the house keeper, McGreevey and the Israeli dude, Spitzer and the call girl, Sanford and the Argentine belle, to name just a few.

Conventional suggests that allowing our partners to fantasize about and freely interact with other people they find attractive is paramount to giving them a license to cheat on us. This view is famously summarized in the Biblical warning that desiring one’s neighbor in one’s heart amounts to adultery. I have to respectfully disagree with the Scriptures on this one: Desiring one’s neighbor in one’s heart is nothing like having sex with that person.

Unfortunately, for many couples, any attempt to control the other’s erotic thoughts and feelings can lead to resentment and frustration. One partner becomes an insecure sexual cop, while the other gets stuck in the unappealing role of a proverbial child waiting to get caught with his or her hand in the cookie jar. So, instead of buying peace and harmony, enforcing monogamy on people’s erotic imagination tends to backfire: When feeling stifled in a relationship, cheating can become a way of asserting autonomy.

For example when we outlaw a particular behavior, like daydreaming about a certain man or woman at work, we tantalize and the prohibition may inspire transgression. Although it might sound counterintuitive, indulging in imaginary cheating—fantasizing about someone other than one’s partner—might strengthen, rather than undermine, monogamous relationships.

Paradoxically, the thought that one's partner might be attracted to somebody else can make the relationship more exciting and titillating. The bedroom scene from Stanley Kubrick’s Eyes Wide Shut portrays an intimate and playful repartee between Alice (played by Nicole Kidman) and her husband Bill (played by Tom Cruise). “Those two girls at the party last night, did you by any chance happen to f— them?” Alice teasingly asks Bill as a prelude to love-making. “Who are they?” she continues smilingly. In response, Bill feigns surprise, though he seems clearly amused and tickled by his wife’s playful . “Some models,” he laughingly confesses.

However, in , one partner’s attempts to acknowledge and share his or her erotic fantasies might rock the boat. For instance, when Alice reveals to Bill her erotic fantasy involving a dapper naval officer, it shatters his illusion that she can only fantasize about him. While Alice never acts out on her extramarital fantasies, her hurt and jealous husband proceeds to seek erotic adventures on the streets of New York.

Like Kubrick’s attractive characters, modern couples need to negotiate a way of using their fantasies about others to feed the erotic tension in their relationship. At the same time, couples must respect the privacy of one another’s erotic thoughts and feelings. Sharing one’s fantasies should be a free act of unilateral self-disclosure, rather than acquiescence to a partner’s demand for transparency or reciprocation.

And if people decide to share their erotic fantasies about others with their partners, they need to proceed with tact and caution.

In , I often invite individuals and couples to examine the meaning of love, eroticism, and sex in their lives. In particular, my patients and I explore the difference between their fantasies and reality. For example, to enjoy a temporary respite from a dreary and cold New York winter, many people fantasize about moving to Hawaii. However, very few of us quit our jobs and head to the airport. Similarly, most erotic fantasies about others do not materialize.

Many people desire and fantasize about their neighbor's spouse (an Israeli dude, an Argentine belle, or Nicole Kidman) without committing adultery. By allowing our extramarital fantasies to play out in the privacy of our imagination, we create the option of not acting them out. Imposing oppressive monogamy on erotic fantasy can lead to resentment and rebellion in the form of sexual infidelity. I encourage my patients to acknowledge their sexual fantasies involving other people, use them to rekindle romance and spice up their erotic lives.

Max Belkin, Ph.D. is a relational psychoanalyst and psychologist. He is a graduate of NYU and the William Alanson White Institute and serves on the editorial board of Contemporary . He teaches graduate courses in couples and individual psychotherapy at NYU. He works with individuals and couples in his private offices in Greenwich Village, New York City, and in Atlantic Highlands, NJ.