The Defining Decade: Why Your Twenties Matter—And How to Make the Most of Them Now

by Meg Jay

Your twenties matter. Eighty percent of life’s most defining moments take place by age thirty-five. Your earning power is decided in your first ten years of work. More than half of us are married, or dating or living with our future partner, by age thirty. Your brain and your personality change more during your twenties than at any time before or after. Your social network is about as big as it is ever going to get. Your defining decade coincides with your peak childbearing years. Meanwhile, your twenties are the most uncertain years you will ever know.

Most have come of age on their devices, where they are bombarded not just with skydiving selfies, but with headlines about economic, political, climatic, and global doom. Even as they feel pressured to get out there and live their best lives, many are unsure about whether their government—or their planet—will survive.

Uncertainty makes people anxious, and distraction is the twenty-first-century opiate of the masses. So twentysomethings like Kate are tempted, and even encouraged, to turn away and be twixters, to close their eyes and hope for the best.

Identity capital is our stock of personal assets. It is how we add value to who we are, and it is what we have to show for how we have spent our time. These are the investments we make in ourselves, or the things we do well enough or long enough that they become a part of who we are. Rather than coming from that “lightning bolt of intuition” Helen wished for, identity capital is how we build ourselves, bit by bit, over time.

The strength of weak ties is the science of how information spreads. It is about how people who do deserve chances or opportunities let other people help them find those chances or opportunities.

What Franklin is describing is something that social psychologists would stumble upon centuries later: the finding that when we do something nice for someone we tend to like that person even more afterward—and this may lead to another favor down the line. This phenomenon is called “the Ben Franklin effect.”

[Society] is structured to distract people from the decisions that have a huge impact on happiness in order to focus attention on the decisions that have a marginal impact on happiness. The most important decision any of us make is who we marry. Yet there are no courses on how to choose a spouse.

By this I mean two things: being alike in ways that matter and genuinely liking who the other person is. Often these go hand in hand. We sometimes hear that opposites attract, and maybe they do for a hookup. More often, however, similarity is the essence of compatibility.

How will we notice—and cultivate—the good things? How should we make time for us? A weekly date or a monthly weekend getaway or a yearly vacation or some combination? What will we do when we notice these things not happening or when money and time are tight?

What does your future look like? Where do you see yourself five, ten, or twenty years from now? Is your future self compatible with my future self?

Why do you like me? What are the things that you like about our life together so far? What is it about me that makes you want to stop looking for someone else?

How will you spend your free time? What does your ideal Saturday or Sunday look like?

William James, the father of research psychology in the United States, said, “The art of being wise is knowing what to overlook.” Knowing what to overlook is one way that older adults are typically wiser than young adults. With age comes what is known as the “positivity effect.” We become more interested in positive information, and our brains react less strongly to what negative information we do encounter. We disengage with interpersonal conflict, choosing to let it be, especially when those in our network are involved. Younger adults, however, are more likely to find negative information—or the bad news—more upsetting and more memorable than positive information—or the good news. MRI studies show that twentysomething brains react more strongly to negative information than do the brains of older adults.

When Danielle called her mother, she was doing what therapists call “borrowing an ego.” She was reaching out in a moment of need and letting someone else’s frontal lobe do the work. We all need to do that sometimes, but if we toss our distress like a hot potato too much, we don’t learn to handle bad days on our own. We don’t practice soothing ourselves just when our brains are in the best position to pick up new skills. We don’t learn how to calm ourselves down, and this in and of itself undermines confidence. Research shows that people who have at least some control over their emotions report greater life satisfaction, optimism, purpose, and better relationships with others.

Real confidence comes from mastery experiences, which are actual, lived moments of success, especially when things seem difficult. Whether we are talking about love or work, the confidence that overrides insecurity comes from experience. There is no other way.

In the twenty-first century, women are likely to be educated, they are likely to have children, and they are likely to have those children later than ever before. For many, it just isn’t feasible—or wise—to have kids before school and work are figured out, and research consistently shows that educated and older parents are more stable, have more resources, and are good for kids. As of 2020, women outnumber men in the workplace, which means that these same women are likely to be balancing career and family roles. Yet, none of this has changed the way our bodies work. It has just changed how much we need to think about family planning—and how much we need to know about fertility.

Present bias is prioritizing the rewards and consequences of the here-and-now over the rewards and consequences of the there-and-then. We would rather have $100 now than $150 next year. We eat the chocolate cake today and say we’ll hit the gym tomorrow. We buy the new jeans today and say we’ll face the credit card bill next month. This isn’t a twentysomething problem. It’s a human problem, one that underpins addiction, procrastination, health, oil consumption, climate change, and, yes, saving for retirement. It is often difficult to imagine and give weight to things that will happen down the line. But twentysomethings are especially prone to present bias. Their brains are still developing the forward thinking it takes to anticipate consequences and plan for the future. And when they do turn to close friends or older others with nervous questions about their lives, they often receive pats on the head and stock phrases like “It’ll work out. You have all the time in the world.”

We do not learn from experience. We learn from reflecting on experience.