Book Summary:

The Defining Decade explores how critical the twenties are to the rest of your life.  Unfortunately the twenties have been described as “disposable years meant for wandering” and Meg dispels this deception. The twenties will either be defining years for the rest of your life, or years that will require you to pay a steep price later, “professionally, romantically, economically, reproductively — for a lack of vision in the your twenties”.

Favorite Quote:

Your twenties matter. Eighty percent of life’s most defining moments take place by age thirty-five. Two-thirds of life-time wage growth happens in the first ten years of a career.” ~ Meg Jay



Cultural, media and other influencers have led us to believe that our twenties don’t matter.  That is simply false.  In fact, the twenties are the most defining years of our lives.  It’s a time period that provides the greatest ease in starting the lives we want.  Making the most of the twenties doesn’t happen accidentally, it takes INTENTIONALITY and good information.

“What is worse are the tears shed by thirty-somethings and forty-somethings because they are now paying a steep price — professionally, romantically, economically — for a lack of vision in their twenties.”

p. Introduction xix

“By 2007, the twenties were dubbed the odyssey years, a time meant for wandering.  And journalists and researchers everywhere began to refer to twnety-somethings with silly nicknames such as kidults, pre-adults, and adultescents.”

p. Introduction xxii


Identity Capital

Identity capital is our collection of personal assets, our life experiences, work experiences, anything that defines us.  These things are not always high GPA’s from ivy league schools and internships at prestigious investment banks.  Meg tells the story about her four years spent with Outward Bound and how that piece of identity capital was more interesting than anything else until she got her PhD from University of California Berkeley.  If you are faced with a decision between opportunities, pick the one with the MOST IDENTITY CAPITAL.

“For some, life may be about neatly building on Phi Beta Kappa or an Ivy League degree.  More often, identities and careers are made not out of college majors and GPA’s but out of a couple of door-opening pieces of identity capital.”

p. 10

Work Experimentation

“That’s why I wish I had done more during my first few years out of college.  I wish I had pushed myself to take some work leaps or a wider range of jobs.  I wish I had experimented — with work — in a way I feel I can’t right now at almost thirty.”

p. 15

Weak Ties – The Power of Networking

Networking or the act of expanding your social and business contacts is extremely important.  Statistically your close friends and family will be less valuable when it comes time to find a job than will those contacts you have only occasional or rare contacts with.

Mark Granovetter found it wasn’t close friends and family — presumably those most invested in helping — who were the most valuable during the job hunt.  Rather, more than three-quarters of new jobs had come from leads from contacts who were seen only “occasionally” or “rarely”.

p. 20

In fact, it is possible that by NOT networking or getting outside our social network of strong ties, might make us WEAKER.

“Rose Coser, called the “weakness of strong ties” or how our close friends hold us back.  Our strong ties feel comfortable and familiar but, other than support, they may have little to offer.  They are usually too similar — even too similarly stuck — to provide more than sympathy.  They often do’t know any more about jobs or relationships than we do.”

p. 21

The Unthought Known (The Tyranny of Should)

Regardless of our perception, we all have a short realistic list of paths we can take based on experience, strengths, weaknesses, etc.  Unthought knowns help us get to this short list of good options.

The tyranny of should is something we all face in life at one time or another.  Not doing what we want to do but rather, doing what we think we should do.  The should do list is largely formed based on outside influencers and can get in the way of “knowing what you know, and acting on it”.

Failing to recognize our unthought knowns and the tyranny of should can lead us of course.

“There is a certain terror that goes along with saying “My life is up to me.”  It is scary to realize there’s no magic, you can’t just wait around, no one can really rescue you, and you have to do something.  Not knowing what you want to do with your life — or not at least having some ideas about what to do next — is a defense against that terror.  It’s a resistance to admitting that the possibilities are not endless.  Its a way of pretending that now doesn’t matter.  Being confused about choices is nothing more than hoping that maybe there is a way to get through life without taking charge.”

p. 33

“Psychoanalyst Christopher Bollas calls the unthought knowns, things we know about ourselves but forget somehow.  These are the dreams we have lost sight of or the truths we sense but don’t say out loud.”

p. 39

“Ian pretended that not knowing what to do was the hard part when, somewhere inside, I think he knew that making a choice about something is when the real uncertainty begins.  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.”

p. 39

My Life Should Look Better on Facebook

Social media (not just Facebook) and our peers manufactured updates can very often leave us feeling under accomplished, unfulfilled and simply behind in life.  Be careful how much stock you place into comparing and contrasting your own life with that of your social media friends.

“Most twentysomethings know better than to compare their lives to celebrity microblogs, yet they treat Facebook images and posts from their peers as real.  We don’t recognize that most everyone is keeping their troubles hidden.  This underestimation of how much other twentysomethings are struggling makes everything feel like na upward social comparison, one where our not-so-perfect lives look low compared to the high life everyone else seems to be living.”

p. 45

The Customized Life

” .. a good story goes further in the twentysomething years than perhaps at any other time in life.    College is done and resumes are fledgling, so the personal narrative is one of the few things currently under our control.  As a twentysomething, life is still more about potential than proof.  Those who can tell a good story about who they are and what they want leap over those who can’t.”

p. 62

“I was worried that by making that [decision to take a job in DC] choice, I was closing all the other doors open to me at the moment.  But it was sort of liberating to make a choice about something.  Finally.  And, if anything, this job has just opened more doors for me.”

p. 64


An Upmarket Conversation

This chapter discusses one of the most important variables to deciding happiness.  Who we marry.

“The most important decision any of us make is who we marry.  Yet, there are no courses on how to choose a spouse.”

p. 69

Who you date in your twenties does matter.

“The chapters ahead are about twentysomething men and women not settling — not settling for spending their twenties on no-criteria or low-criteria relationships that likely have little hope or intention of succeeding.”

p. 79

Picking your Family

As the saying goes, “you cannot pick your family.”  This chapter outlines just how false this is.  Indeed, through marriage, you an pick your family and you should pick wisely.

“What no one tells twenty-somethings is that finally, and suddenly, they can pick their own families — they can create their own families — and these are the families that life will be about.  These are the families that will define the decades ahead.”

p. 88

The Cohabitation Effect

This chapter examines the misconception that cohabitation before marriage is a good test for marriage.

“..couples who live together first are actually less satisfied with their marriages and more likely to divorce than couples who do not.  This is what sociologists call the cohabitation effect.”

p. 91

“It is the couples who live together before being clearly and mutually committed to each other who are more likely to experience poorer communication, lower levels of commitment to the relationship, and greater marital instability down the road.”

p. 95

On Dating Down

If you don’t like the story you’re currently living out in relationships or work, take the time to re-write it.  Or, you will relive the same story again and again.

“Twenty-something women and men who are dating down — or working down, for that matter — usually have untold, or at least unedited, stories.  These stories originated in old conversations and experiences and, so, they change only through new conversations and new experiences.”

p. 110

Being In Like

A common misconception about compatibility in relationships is being “alike”.  However, we often match ourselves based on relatively obvious criteria such as age, religion, attractiveness, political affiliation, etc.  Research shows however that personality likeness might be the best judge of marital success.  There are five qualities included in personality that Meg refers to as “The Big Five”.

“The Big Five refers to five factors that describes how people interact with the world:  Openness, Conscientiousness, Extraversion, Agreeableness, Neuroticism.”

p. 118

The Brain and the Body

Forward Thinking

The human brain goes through two major development phases.  The first phase occurs in the first 18 months where the brain produces far more neurons than it can use, ready to tackle whatever live throws its way.  Neurons not used or neglected, get pruned off.  The second phase happens in adolescence and finishes in the twentysomething years.  The second phase is not about learning language and how to tie shoes.

“[during the twenties] jobs teach us about regulating our emotions and negotiating the complicated social interactions that make up adult life.  Work and school are our best chance to acquire the technical, sophisticated skills needed in so many careers today.  Relationships are prepping us for marriage and our partnerships.   Plans help us think across the years and decades ahead.  Setbacks ready us for handling our spouses and bosses and children.  We even know that larger social networks change our brains for the better as they require us to communicate with more and different others.’

p. 141

Calm Yourself

The twenties are full of many new and surprising things as life pivots from college to professional life. When a human being is surprised by something new, evolutionary theorists refer to these moments as flashbulb memories, memories that are more vivid. It is important to understand what is going on so that you can focus on keeping calm through these events.

“Twentysomething’s take these difficult moments particularly hard. Compared to older adults, they find negative information – the bad news – more memorable than positive information – or the good news. MRI studies show that twentysomething brains simply react more strongly to negative information than do the brains of older adults.”

p. 149

Outside In

Confidence is gained slowly as experience is accrued.  Based on research from K. Anders Ericsson, it takes 10,000 hours of work experience to become an expert. True confidence is gained from the outside in, through accomplishments at work and experience earned.

“Inaction breeds fear and doubt. Action breeds confidence and courage. If you want to conquer fear, do not sit home and think about it. Go out and get busy.”

-Dale Carnegie

“Confidence doesn’t come from the inside out. It moves from the outside in. People feel less anxious – and more confident – on the inside when they can point to things they have done well on the outside.”

p. 159

Getting Along and Getting Ahead

Twentysomethings that are committed to either a job or a relationship (or both) are happier than those who are not. Goals and goal setting is a fantastic way to structure your life and ensure your commitments are fruitful and whatever our life goals are, every day you’re working toward them.

“Goals are how we declare who we are and who we want to be. They are how we structure our years and our lives. Goals have been called the building blocks of adult personality, and it is worth considering that who you will be in your thirties and beyond is being built out of the goals you and setting or yourself today.”

p. 171

Every Body

By the numbers, twentysomething’s top priorities are 1) being a good parent someday and 2) having a successful marriage. It is worth spending some time understanding the upside and downside of postponing marriage and having kids.

“According to a National Survey of Family Growth, about half of childless couples are not childless by choice. They are thritysomething and fortysomething women and men who feel they did not consider the facts about fertility soon enough, like maybe when they were twentysomething’s who, even if they weren’t ready to have children, could have planned work and family trajectories with different outcomes.”

p. 183

Do The Math

Good stories and happy endings are intentional, not accidental.  How to you maximize your possibility of ending up where you want in life?

John Irving states, “I always begin with the last sentence; then, I work my ay backwards, through the plot, to where the story should begin.”

p. 198

The point is that being intentional, having a plan matters.  Now, every day.  Time is limited for everyone.  Make the most of it!

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