The way I see it, a good marriage is a lot like a good sparring match. It’s a formal partnership, an agreement between two people who promise to challenge, protect, and nurture each other. That may seem like an odd analogy but sparring—as distinct from fighting—is very much a teaching and learning process. In marriage as in sparring, you have to agree on certain boundaries, because you are entering into a relationship that leaves you very vulnerable. You have to trust your partner. It’s risky, but the assumption we make when sparring or marrying is that the risk is acceptable when compared to the potential rewards of trusting our partner.