Book Notes — The Defining Decade by Meg Jay



January 2021

Disclaimer: These are the personal notes I took, so I haven’t explicitly quoted most of the passages that I wrote down. Some of the quotes have merged with my own writing, & I’m not sure which is which anymore. Assume all the good parts came from the author & all the bad parts came from me.

Rating: 7/10

When It's Useful: If you're in your twenties and feel either lost, unambitious, or just need more motivation.


After hearing Nat Eliason recommend The Defining Decade, I quickly ordered & read through it. I found it as a great boost of motivation to keep me focused & intentional about what I do during my 20s. I already knew this age is critical, but it was a refreshing reminder to make sure I build momentum that carries me through the rest of my life.

My notes copy the same structure as the book. It’s broken up into three sections — work, love, and brain/body.


Identity Capital

  • In order to have a successful career, there are things we must do to build ourselves up. One of these is forming identity capital. Identity capital include the skills we learn, the jobs we do, and the actions we take that showcase our values and experiences.
  • To form a more robust identity, you must be thoughtful about what you do. The author discusses the concept of being underemployed, where you are working a job that doesn’t challenge or take advantage of your current skills. To counteract this, make sure you develop a bias to action. Rather than constantly exploring and thinking about what you want to do, take action to build up foundational skills that make up your identity capital.
  • Make commitments while you explore. It’s fine to try out new jobs & hobbies, but if you don’t commit at all, then you’ll be forming a weak identity around many different things. Without a strong identity, you’ll feel lost & lack direction, which will prevent you from building significant momentum later on. Again, it’s fine to pivot, but make sure you commit rather than switch up too often.

Weak Ties

Everything can change in a day. Especially if you put yourself out there.
  • Weak ties are relationships that are typically underutilized by people in their twenties. These relationships are more distant, like colleagues, old friends, or people you’ve known for a short time. However, these relationships can be valuable for many reasons.
  1. Many people land a job in a competitive market through referrals. If you don’t know anyone, it may be harder to land these competitive jobs. To phrase it another way, referrals make it easier to land jobs. Cultivate these relationships, and don’t be afraid to ask. This doesn’t mean take without giving back — make sure these relationships aren’t transactional. Provide value to them, even if it’s just having an interesting conversation. But to emphasize the point again, don’t talk yourself out of asking for help. If you don’t ask, the answer is always no. Do your homework & have a clear ask about exactly what you want.
  2. These relationships also broaden your perspective. We tend to think similarly to those closest to us, but if we don’t have a range of perspectives, we will think through a narrow lens.
  • There’s a caveat, however. While you should actively seek out a diverse network of relationships, it’s also beneficial to join a group of friends with similar aspirations to you. If you want to develop a career as a writer, it’d serve you well to find a group of friends where it’s normal to earn money through writing. Otherwise, your current friend group may plant seeds of doubt on the viability of your aspirations as a career path since it’s not normal for them. This applies to any profession — entrepreneurship, art, etc.


  • As we grow up with our education system, there’s a sense of certainty that permeates our life. If you study hard & get good grades, you’ll get rewarded. But life after college is uncertain. There’s no direct path you can follow with certainty, and this experience isn’t something we’re  prepared for with the standard education system. We may know what we want, but not how to get it. Although we open ourselves up to failure, we also create higher potential upside. There’s more freedom when you deal with uncertainty. It’s simultaneously frightening and liberating.
  • The author asks a few helpful questions:
  1. What would you do if you didn’t win the lottery?
  2. Can you do something well enough to support the life you want?
  3. What would you enjoy working on for years to come, that is still sustainable to live off of?
  • Social media also adds fuel to this fire of confusion as you start developing a “should” mentality. You start to compare yourself and think about what you should do rather than what you want to do. This doesn’t mean blindly follow your passion, it simply means to be thoughtful about what you choose. Find a cross-section between what you’re interested in & what skills you want to develop, then double down on them and learn those skills well.
  • You have to recognize your own potential & how your particular gifts, limitations, and inclinations fit with the world around you. If you can overcome this fear of uncertainty & confusion, you can start to take action towards the life you want. It may take time & a lot of rejection, but it’s always worth the effort.

Interviews & Jobs

  • Most of the time, recruiters deal with the same monotonous applications & resumes. Creative cover letters or applications stand out in relief, which is why you should always put in the extra effort to stand out. Limit the companies you want to work for & go above and beyond for the companies you do choose.
  • A good story goes further during your twenties than perhaps any other time in life. You have control over your personal narrative, so craft it wisely. For the most part, your early twenties are 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.
  • Resumes are uncompelling lists, so you have to craft a great story around your life instead. Create a sharper narrative that weaves in your relevant interests, talents, and experiences. It must balance complexity — too simple & you will seem inexperienced, but too complex & you will seem disorganized & confused. It’s a valuable exercise as you can take this with you to interviews & coffee dates.
  • When crafting your story, be introspective. Sometimes, the reasons you made a certain decision feel clear to you but not the listener, so take time to examine & craft your story in a way that makes sense to others.
  • Interviewers want to hear a reasonable story about the past, present, and future. How does what you did before relate to now, and how will that get you to what you want to do next? The burden is on you, the applicant, to demonstrate that working here makes sense beyond just wanting a job. This is also why it’s good to narrow down on the few companies that you need to work at rather than ones with good pay & benefits.

Love & Relationships

  • The main message here is around being intentional & making sure you understand the benefits of compounding. Don’t wait until your thirties to find someone you want to spend the rest of your life with. However, if you want to to increase the likelihood of your relationship succeeding, be wary of a few common problems.
  • One problem the author discusses is cohabitation. Living together before marriage is fine, but don’t expect it to imitate marriage. You must be clearly & mutually committed to each other before deciding to move in together — don’t slide into it. If it “feels convenient” rather than being an intentional choice, then you’ll be likely to experience negative effects down the road, like poorer communication & lower levels of commitment to the relationship.
  • The best point I found in the book was around stress testing your relationship, so you can see how your significant other acts under stress. Backpacking to different countries is one of the best ways to do this because you can see how your partner treats others, manages time, deals with uncertainty & problems that come up (like getting sick or booking the wrong flight), and what activities they like to do while traveling. You will have great experiences, like hiking & exciting adventures. But you also can’t get away from each other and have to deal with the unfamiliar. Money might be tight, and you may get sick, sunburned, or bored. It’s a great bonding experience since it provides a difficult yet amazing experience. Additionally, you can also identify what interests you have in common. Do you like partying or staying indoors? Are you both indecisive? Do you both stick to a budget?
  • It’s important to find the similarities that matter. The more similarities two people have, the more they are able to understand each other, to appreciate how the other acts and sees the world. Two people who are similar will have the same reactions to a rainy day or a long trip. But not all traits should be evaluated equally.
  • Most people have their own criteria & dealbreakers they evaluate with, either implicitly or explicitly. This “rubric” helps weed out people easily —it identifies the qualities you feel are non-negotiable, like having kids or being religious. One criterion the author mentions as an important trait to evaluate is a similarity in personality. This is harder to categorize since it’s more about how we operate in the world & is a part of everything we do. This is why stress testing your relationship is so powerful — it shines a light on parts of their personality that aren’t as easily visible. The Big Five is a common way to break down a person’s personality.
  • Make sure you’re aware of what similarities hold more weight. Diversification of skills & interests is helpful since needs in marriage change over time — differences keep life fresh.
  • In summary, focus on personality as one of your criteria. Learn how your significant other operates in the world. Don’t expect them to change, at least personality-wise. If you go into a relationship thinking they’ll act differently, you’ll be let down. Be picky about the similarities that matter, like ambition, goals, & personality — don’t focus on the everyday things. There will always be differences, so find the ones you can overlook. Make sure to create a shared vision of what you want your life to look like together.

Brain and Body

  • Most of the examples in this section were about confidence in your career, like dealing with imposter syndrome. One thing the author discusses that I’ve personally noticed is how important it is to solve problems on your own.
  • I only recently found a ”mentor” that I looked to for advice, but I realized I started asking for too much help. When you externalize your distress too much, you don’t learn to handle the bad days on your own — you let someone else’s frontal lobe do the work. This is partly due to the fact that I’ve never had a confidant for my career before, so it was a new experience. The main point is to be selective about what you ask for help with rather than running to someone for any & every problem you have.
  • Develop a growth mindset. Failures may sting, but when you have a growth mindset these failures are viewed as opportunities for improvement & change, not as a deterministic outcome.
  • The confidence you need in anything you do, whether it be love, work, or skills you learn, comes from experience. Confidence stems from trusting yourself to get the job done, whether that is public speaking, sales, teaching, or anything else. That trust comes from having gotten the job done many times before. So practice relentlessly to cultivate that confidence.
  • To develop that confidence, the work has to be challenging & requires effort. It has to be done without too much help & can’t go well every single day. Without stress, you won’t grow. Confidence comes from succeeding, especially after surviving some failures. We tend to remember negative events more, & so making mistakes allow us to learn & solidify those lessons. I bet you can remember a major or minor mistake you’ve made recently without trying too hard. But because of that, you won’t forget the lesson you learned from it either.
  • On the note of imposter syndrome, sometimes you don’t give yourself enough credit for the experience you’ve already developed. As an exercise, list out the relevant things that you’ve done towards the job or person you want to become — and don’t be self-deprecating.
  • Your twenties are the best time for change. You can go from socially anxious to confident quickly if you put in the effort.
  • Goals are how we declare who we are and who we want to be. They form our personality & the structure of our lives. They provide us with direction.
  • We tend to discount the future & favor the rewards of today over the rewards of tomorrow. $100 this month vs $150 next month. It’s understandable, but it also underpins negative things like addiction & procrastination. Practice looking forward & practice understanding the power of compounding.
  • Good stories & happy endings are more intentional that you might think.
  • Rephrased quote — Almost every twentysomething wonders “will things work out for me?” The uncertainty behind that question can be daunting. It’s also why deliberate action is so necessary. It’s unsettling to not know the future and, in a way, even more daunting to consider that what we are doing with our twentysomething lives might be determining it. There’s no formula or right and wrong way to live life. But there are choices and consequences.
  • Be deliberate about changing your future, otherwise you’ll be missing out on the upside. You'll deal with uncertainty when making decisions, but if you take action, you will be more likely to gain control & freedom over your life.
  • “Claim your adulthood. Be intentional. Get to work. Pick your family. Do the math. Make your own certainty. Don’t be defined by what you didn’t know or didn’t do.”
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by Amaan