I first read this book coming out of university. It had interesting tidbits—I learned about cohabitation, identity capital, and the Ben Franklin effect. But it didn’t stick with me. The sections are Work, Love, and The Brain and Body (aka Transformation)—I didn’t have have a job, just a bit of relationship experience, and I sure as hell didn’t know who or what I wanted to become. So I breezed through it, made a few highlights here and there, and moved on to the next book.

Two years later, I read it again and this time it left a profound impact on me, so much so that I wrote and organized the notes below. The fun tidbits were still there, but what stuck with me was the intentionality the author proposes. The intentionality to change your personality to become who you want to be, to take steps to build the life you want to have, in the decades to come.

This time, I had an emergent career, more experience with love, and a better idea of who I wanted to become. This book came at the perfect time to help me on my way.

Summary

• The twenties are biologically consequential, representing a critical period—a time when we are primed for disproportionate growth and change. Modern society presents an opportunity to capture and intentionally mold that critical period to fit the adult life we want to have.

• The patterns we act out in our twenties set us up for our thirties and beyond. Jay proposes taking charge to intentionally choose these patterns, both in work (setting yourself up for your desired career, rather than working odd entry-level jobs) and love (dating people you’d actually want to marry, instead of random people).

  • “Never again will we be so quick to learn new things. Never again will it be so easy to become the people we hope to be. The risk is that we may not act now.”

• We create positive personality change in the twenties by making commitments—to relationships, jobs, places to live—or by making progress, and gaining confidence, in these areas. Making commitments and choices builds character and ultimately feels more fulfilling than avoiding them.

  • Aside from commitments, even goal-setting is important for confidence and happiness: “goals are the building blocks of adult personality.” “Goals are how we declare who we are and who we want to be.”

---

Full notes

Work

Identity and making choices

• Identity crises are solved by collecting identity capital, our personal collection of experiences, skills, personality traits, and behaviors that allow us to “build ourselves up”.
• Twentysomethings who take the time to explore and also have the nerve to make commitments along the way construct stronger identities.
• You can’t think your way out of an identity crisis; “you can’t think your way through life. The only way to figure out what to do is to do—something.”

• Uncertainty from overwhelming choice or otherwise not making choices is a choice. It seems safer, but it’s just a way of pushing consequences down the line.

  • “Being confused about choices is nothing more than hoping that maybe there is a way to get through life without taking charge.”
  • “The more terrifying uncertainty is wanting something but not knowing how to get it. It is working toward something even though there is no sure thing. When we make choices, we open ourselves up to hard work and failure and heartbreak, so sometimes it feels easier not to know, not to choose, and not to do. But it isn’t.”
  • Comparing yourself to others, to what you “should” be doing, is toxic. Goals direct us from the inside, while shoulds are “paralyzing judgments from the outside”.

Practical suggestions

• Weak ties (people you sort-of know, friends of friends, former colleagues, etc.) are more transformative than close friends and family when it comes to new jobs, relationships, or opportunities.

  • “New things almost always come from outside your inner circle.”

• The Ben Franklin effect: Strong ties may do us favors if they like us, but weak ties start to like us if we ask them to do us favors.

  • “Perhaps the single best thing we can do to make our own luck in our twenties is say yes to our weak ties or give them a reason to say yes to us.”
• A good story is the key differentiator between equally-qualified twentysomethings. Interviewers want to hear a story that makes sense about how what you did before connects to what you want to do now, and how that might get you to your next step.

Love

Intentionality

• Society propagates the idea that relationships are something we can’t plan for, unlike careers. But around age 30, there’s a bait-and-switch, when suddenly people start to focus on marriage and not getting “left behind”. Jay proposes a more intentional approach to relationships and commitment.
• Far from safeguarding against divorce, cohabitation muddies the waters of intentionality and commitment due to lock-in. It’s easy to slide into cohabitation, then to marriage, purely due to convenience instead of active choice.
• You have a second chance to pick and create family (in-laws, children) when you marry.
• In adolescence, we first attempt to form life stories about who we are and why, which we carry from place to place, from people to people. People who date down or work down in their twenties are often following narratives that are untold, or unedited since adolescence. Since they originated from old conversations and experiences, it takes new conversations and experiences to change them.

Compatibility

• Relationship compatibility is built on similarity across many dimensions, the most important of which may be personality: how we are in the world.
• Distinguish deal breakers from match makers; not having deal breakers is a necessary, but not sufficient condition for a happy relationship.

Personality

• “One of the simplest and most widely researched models of personality is what’s called the Big Five: openness, conscientiousness, extraversion, agreeableness, neuroticism.”
• “Neuroticism—the tendency to be anxious, stressed, critical, and moody—is far more predictive of relationship unhappiness and dissolution than is personality dissimilarity.” Any two people will have differences, but reacting to those differences negatively leads to criticism and contempt, the two leading relationship killers.
• What we need in marriage changes over time; early on, a couple’s similarities feel comforting, but later on, their differences can help overcome new challenges and keep the marriage fresh.

The Brain and the Body

The greatest opportunity

• In our twenties, the “emotional brain” is fully developed while the “rational brain”, the prefrontal cortex, is still developing.

• The brain has two “critical periods”, in which new neurons sprout explosively and connections are subsequently pruned in a use-it-or-lose-it fashion. The first critical period is in the first 18 months of life; the second, in adolescence and ending in the twentysomething years.

  • Just as how children absorb languages from their environment, twentysomethings are especially sensitive to their environments, be it work, school, social interactions, relationships, life planning, dealing with setbacks.
  • “We become what we hear and see and do every day. We don’t become what we don’t hear and see and do every day.”
  • “Never again will we be so quick to learn new things. Never again will it be so easy to become the people we hope to be. The risk is that we may not act now.”

Emotional stability

• Twentysomethings are generally less emotionally stable than older people; their brains find negative information more vivid and memorable. With age, comes what’s known as a positivity effect.
• Reappraising negative situations with facts lessens bad feeligns.

Confidence

• Confidence comes from practice, experience, and mastery; there is no other way.
• Those with a growth mindset ultimately find more success because they’re not threatened by challenges and struggles. They work harder or find new strategies. Those with a fixed mindset shut down when things get tough and don’t progress further.

Change

• “We now know that, of any time in life, our twenties are our best chance for change. I have seen twentysomethings move from socially anxious to socially confident-enough, or get beyond years of childhood unhappiness, in a relatively short period of time. And because these changes are happening just as long-term careers and relationships are being decided, these same shifts can lead to very different lives. The twenties are a time when people and personalities are poised for transformation.”
• Our personalities don’t change after thirty; the debate is between whether they change a little, or don’t change at all.

• We create positive personality change in the twenties by making commitments—to relationships, jobs, places to live—or by making progress, and gaining confidence, in these areas.

  • Aside from commitments, even goal-setting is important for confidence and happiness: “goals are the building blocks of adult personality.” “Goals are how we declare who we are and who we want to be.”

Timelines

• Envisioning and setting goals for what you want in your 30s, 40s, 50s infuses urgency and purpose in the twentysomething years. Time is limited, and we need to create our own sense of it. Even a timeline may help.

  • Our twenties can be like living beyond time after we lose the structure of school. “There’s this big chunk of time and a whole bunch of stuff needs to happen somehow.”
  • Present bias is also harmful: we favor rewards today vs. delayed rewards in the future. But these sorts of “now-or-never behaviors” that we choose don’t make us happy for long.

Children and fertility

• Jay advocates for those who want children to have them earlier. Fertility for women peaks in the late 20s and drops at around 35, past which pregnancy becomes more stressful, time-consuming, and error-prone. For men, “older sperm may be associated with neurocognitive issues in children like autism, schizophrenia, dyslexia and lower intelligence.” [Saha, Barnett, Foldi, Burne,, “Advanced Paternal Age is Associated with Impaired Neurocognitive Outcomes”].

  • (Jay also seems to think that having children is one of the most meaningful things you can do, citing a man who wished he had had his kid earlier so that he could spend more healthy time with him. The man felt that nothing he did in his twenties could compare with spending time with his wife and kid.)