The Defining Decade: Why Your Twenties Matter — And How to Make the Most of Them Now
by Meg Jay
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The Net-Net
The Defining Decade is a bracing assessment of the choices, opportunities, and potential pitfalls facing individuals in their twenties. Leveraging decades of experience as a developmental clinical psychologist, Dr. Meg Jay argues that our twenties are the best time to make the important decisions about our careers, relationships, and health that can set us up for happiness and success for the rest of our lives. Whereas many believe that one’s thirties are when life’s most important moments take place, Jay believes that individuals who make deliberate, thoughtful life decisions in their twenties will get more out of life than those who don’t — both in their twenties and in the decades that follow. As a first-of-its-kind direct appeal to so-called “twentysomethings,” The Defining Decade is a must-read for anyone seeking a framework for navigating young adulthood.
Top 3 Insights
- Doing something later does not always mean you will do it better. This point is most salient during Jay’s discussion of romantic relationships, during which she cites research concluding that divorce rates have remained steady in America, even as the average age of those getting married rises. Jay also advocates for approaching careers with this later-is-not-better mindset, as she shares several stories of twentysomething patients whose professional fulfillment was stifled or delayed by their belief that one’s thirties are the time to really “figure out” work. While patience can lead to more thoughtful actions, indecision and an “I’ll figure it out later” attitude can facilitate missed opportunities, regret, and unnecessary stress.
- We become what we hear and see and do every day. Jay introduces the neuroscience concept known as “the survival of the busiest,” which says that our brains become primed to perform the actions most commonly asked of it. In other words, the “busiest” neurons and and connective pathways become the strongest. One’s twenties are a particularly fruitful time to understand and take advantage of this concept, Jay argues, because research suggests that the brain’s plasticity — its ability to change and be molded by our behaviors — declines substantially after our twenties. Therefore, building strong habits and behaviors in our twenties is critical to becoming the future selves we desire to be.
- Leverage “weak ties” in your network. Common convention holds that building a strong network of close relationships pays dividends throughout one’s life in the form of career opportunities, friendships, and interesting life experiences. Building on this notion, Jay presents research and anecdotes suggesting that second or third-degree network connections can actually be just as valuable as deeper relationships. People generally enjoy helping others — even complete strangers — and one’s twenties are a perfect time to leverage this aspect of human nature to help launch you toward a personal or professional goal. The key to this tactic for twentysomethings, Jay says, is to first have a clear idea of what you want, and then have the courage to ask for it.
Actionability
Through her effective advocacy of the importance of our twenties, Jay leaves readers inspired and motivated toward productive action. After reading The Defining Decade, you’ll likely have a new outlook on your twenties, and may even feel an immediate sense of urgency to be more decisive in an area of your life that’s been lagging. All in all, Jay’s artful and persuasive proselytizing is effective in instilling a thoughtful and action-oriented mindset in twentysomething readers.
- Consider how “weak ties” could help me reach an important goal.
- Track my screen time and social media usage for one week to become more self-aware about how I’m spending time.
- Share this book with another twentysomething!
Good Stories
The book’s stories are largely anonymized retellings of Jay’s interactions with twentysomething patients, which go a long way toward illustrating the book’s main points but are not particularly memorable or worth sharing with others. To make the book’s content even stickier and more entertaining, Jay could have better leveraged examples from history or popular culture.
- Benjamin Franklin benefitting from the power of reciprocity while attempting to win over a fellow legislator in Pennsylvania’s House of Representatives.
- Jay’s discussion of the “Cohabitation Effect,” which is the counterintuitive finding that couples who live together before marriage are more likely to get divorced than couples who don’t.
- Inclusion of scientific research about the biological realities of being in your twenties — from fertility, to brain plasticity, to psychological biases, and more.
Key Quotes
- “If we can figure out how to navigate [our twenties], even a little bit at a time, we can get further, faster, than at any other stage in life. It is a pivotal time when the things we do—and the things we don’t do—will have an enormous effect across years and even generations to come.” (xxxv)
- “A more expansive sense of interconnectedness rests not on texting best friends at one in the morning, but on reaching out to people that make a difference in our lives even though they don’t have to.” (28)
- “Picking your family is realizing you have choices—and owning them—rather than pointing the finger at, or waiting around for, luck or fate or Cupid or chemistry. Picking your family is having the audacity to put together the sort of family you want and need—whatever that is.” (94)
- “Twentysomethings hear they have infinite time for the dreaded adult things but so little time for the purportedly good stuff. This makes living in the present easy. It’s connecting the present with the future that takes work.” (228)
If This Were an MBA Class, it Would Be Called:
Building the Rest of Your Life
Best For:
- Twentysomethings seeking direction and motivation
- Anyone contemplating a career change
- Managers who frequently interact with entry-level employees
Can’t get enough? Consider:
- Meg Jay’s TED Talk: Why 30 is not the new 20
- What’s the Point of Your 20s? Ask the Patron Saint of Striving Youth (The New York Times)
- Graham Weaver at Stanford GSB: “How to Live an Asymmetric Life”
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