Greg Epstein serves as the Humanist chaplain at Harvard University, and is the author of the New York Times bestselling book "Good without God." For much of the last two years, he's also served on-screen as the Spiritual Advisor of the popular—and controversial—reality TV show, "Married at First Sight," which matches pre-screened men and women in real, legal marriages that take place the first time they meet. We spoke to Greg about what he's learned about love from the social experiment, the seduction of "magic" in marriage, and what his own first year as a newlywed has been like.

Motherly: What does marriage mean today in modern American culture?

Greg: For the widest swath of Americans, marriage is now about trying to find intentional fulfillment in a deep and lasting human relationship. It's no longer about economics for most of us—at least not primarily. It's no longer about religious requirements, even for most religious people. It's no longer about custom, tradition or honoring one's family, even though marriage does have elements of many of these things.

The primary reason why most American are getting married is that we are seeking a sense of fulfillment through a lasting, committed relationship with another human being.

That's a hard thing to achieve. It's a lofty goal. It's a goal that is of course realistic in many ways, but is also unrealistic in some ways. "You can't fool all the people all the time," and you can't be completely fulfilled all the time with another person. It's not something you're going to be able to feel or experience every moment.

Motherly: Talk to us about 'Married at First Sight." Do you see it as an arranged marriage, or something else?

Greg: It's not an arranged marriage. Arranged marriages often involve tremendous pressure, usually on the woman. The couple often locks themselves into an arrangement that is governed more by tradition and people outside than by what will be right or fulfilling for them.

Instead, we see it as a social experiment. The idea is that we are trying to help people overcome some of the difficulties they have around making good decisions in relationships.

We’re trying to see if we can take six individuals and help them, give them coaching, and select them for their potential for growth and help them to learn from us and one another about what it takes to be more happily married. We’re hoping that a large audience of people could get some educational benefit from watching that.

I just want people to make better decisions for their long term relationships.

Motherly: [Four of the couples from two seasons have broken up, but two have stayed together.] Why does it sometimes work?

Greg: It works sometimes because there are a lot of good people out there who really want a good relationships and are willing to work at it but really haven't had the opportunity to learn about themselves and about another person in a way that could make it work. There is a huge assumption in our popular culture that marriage and love is about magic. If all you want in magic in your love relationship you better go find Aladdin because it ain't coming from normal human life.

Motherly: What can we learn from the couples that stayed married?

Greg: From the couple that succeeded, these individuals were willing to look at themselves and do the required work to understand themselves better before pointing the finger at the other.

On the show, Jason, for example, was willing to do that. He has had tendencies to go off on his own and be emotionally unavailable like many men, but he was willing to look at that in himself and say 'I really want a good marriage so I'm going to work on that. Courtney was willing to work on parts of herself, too.

Doug and Jamie and rare very good example of this. Doug had to work very hard to win Jamie's affection but he also had to look carefully at himself when he screwed up and as he continued to make mistakes, I've found him often to be willing to say 'I screwed up. I apologize and I'll do better next time."

I give those individuals a lot of credit. That's what it takes first and foremost is a willingness to do the hard work of being the right partner as opposed to just finding the right partner.

Motherly: You, too, are recently married. As you've been working on the show and living as a newlywed, what have you learned about love?

Greg: I think love is surprising all the time. You can't predict it. Even when it's predictable you can't predict that it's going to be predictable. Like a lot of people I've learned both how hard love can be and how transformative, in a positive way, it can be when it's going well.

I'm a better person and I'm better at life because I’ve committed to loving a person who is a good person and who is good for me. We struggle with it like everybody else because we’re human beings and we have our flaws and we also have two different narratives and two different life experiences. There's plenty of surprise in terms of getting engaged and being married in the first year that I'm following these marriages of other people on the show whose lives we helped shape.