Marry for love? For most of history, the idea would have seemed silly.

Marriage was essential for day-to-day survival, for reproduction and social acceptance. People fell in love, of course, but that wasn’t what marriage was about.

Today, we marry for love. And so much more. How did we get here?

Let’s look to Abraham Maslow as our unlikely tour guide. Maybe you learned in Psych 101 about his hierarchy of needs, with physiological and safety needs at the bottom, belonging and love needs in the middle, and esteem and self-actualization needs at the top. Like a video game of life, you can’t get to a higher level until you’ve met the ones below it.

For thousands of years, spouses were workmates — they struggled together, toward the bottom of the hierarchy, to produce the food, clothing, and shelter required to survive.

Starting around 1850, in the United States and some other Western nations, the industrial revolution increased efficiency enough that more people could meet those low-level needs without being married. For the first time ever, personal fulfillment became a primary goal of marriage, which jumped up to the love and belonging level. Spouses went from work-mates to soul-mates.

But this early version of soul-mate marriage was based on the idea that men and women should adhere to radically different gender stereotypes in order to inspire love. The assertive breadwinner married the nurturing homemaker.

In the 1960s, people became fed up with this stifling of their individuality and staged a full-on revolt against the constricting social roles. Freedom of expression and individual authenticity became the Holy Grail.

Today, we still marry for love, but we also require that our partner help us grow toward our authentic self.

Michelangelo said that sculpting is not about creating a sculpture, but about revealing it — chiseling and polishing the block of marble to reveal the beautiful form slumbering within. Similarly, married people began looking to their partner to sculpt away their flaws and insincerities, bringing forth the authentic self buried inside.

The climb up Maslow’s hierarchy creates a paradox. On one hand, as our expectations become increasingly complex, more marriages fall short. To meet our highest needs, our partner must understand us profoundly. Even if we invest tons of time and effort in the relationship—which most of us aren’t doing—there’s no guarantee we’ll attain this level of understanding. From this perspective, it’s no surprise that the divorce rate doubled between 1960 and 1980, reaching 50%, or that the average marriage is less satisfying today than it was a few decades ago.

On the other hand, the best marriages today are better than the best marriages of earlier eras. When they do manage to fulfill people’s highest needs, couples can achieve, in Maslow’s words, “profound happiness, serenity, and richness of the inner life.”

Aiming for the top of the hierarchy leaves many people disappointed by a marriage that would’ve been good enough for our grandparents. But it also puts within reach a level of marital fulfillment that grandma and grandpa wouldn’t have dreamed possible.

For more on the history of marriage, and specific #lovehacks designed to help you achieve a marriage at the top of Maslow’s hierarchy, read Eli’s new book The All-or-Nothing Marriage (https://goo.gl/d1rQaz)

For more writing on love, dating, and relationships, follow Logan at facebook.com/loganury or subscribe to her newsletter here