• Along with the direct impacts of technology, individualism and a slower life trajectory are the key trends that define the generations of the 20th and 21st centuries.
  • ——Jean M. Twenge, Generations,1 p. 8
Jean Twenge has assembled a wealth of information about how the attitudes, behaviors, health, and economic circumstances of Americans have changed over the last several decades. Her latest book is packed with interesting charts and tables, filling my notes from the book with facts and observations to chew on.

The questions that Twenge chooses to explore are interesting. When did Americans start marrying later and having fewer children, and will this trend continue? How economically disadvantaged are Millennials (born between 1980 and 1994)? As young people age, are they becoming as conservative as their parents? She answers these and other questions with evidence that appears to be well chosen and reliable.

Nonetheless, I was not always pleased by Twenge’s manner of presentation. She frequently augments a data point by adding “perspective.” For example:

  • If fertility rates had stayed the same between 2008 and 2019 instead of declining, how many more American babies would have been born? The answer: 5.8 million babies… 5.8 million is more than the entire population of Norway. (p. 476)

The Norway comparison strikes me as gratuitous. It is as if Twenge does not trust a reader to be able to process the number 5.8 million. At best this is condescending. At worst it is an attempt to enlarge the number in the mind of the reader. Her “perspective” almost always nudges in that direction.

I also am skeptical that the generational framing works as well as she claims. Twenge writes:

  • The era when you were born has a substantial influence on your behaviors, attitudes, values, and personality traits. In fact, when you were born has a larger effect on your personality and attitudes than the family who raised you does. (p. 2)

But her analysis reveals that there is a lot going on aside from generational eras. She herself often spells out trends that differ by gender, level of education, and other demographic characteristics.

Birth year per se is not a likely causal variable. It is true that certain events will affect some cohorts more than others. Examples include the terrorist attacks of 2001 or the financial crisis of 2008. But Twenge does not regard such events as the most important determinants of generational attitudes.

Twenge puts technology front and center as a causal variable. She focuses on discrete changes in technology, notably the Internet, the smart phone, and social media. These innovations emerged when different generations were at different ages.

  • Computers and email cleaved Gen X from Boomers, texting Millennials from Gen X, and TikTok Gen Z from Millennials. (p. 156)
“With greater college attendance and fewer early marriages, young people are spending more time in what seems to older generations like adolescence. Moreover, it seems like an adolescence that is less adventurous and more sheltered.”

Other causal variables operate more gradually. One trend is toward a slower life trajectory, by which she means starting later to join the work force and form a household. With greater college attendance and fewer early marriages, young people are spending more time in what seems to older generations like adolescence. Moreover, it seems like an adolescence that is less adventurous and more sheltered.

Individualism is a trend that predates the twentieth century, but Twenge sees it accelerating recently. For her, individualism is:

  • … a worldview that places more emphasis on the individual self… Individualistic cultures such as the U.S. value freedom, independence, and equality, while more collectivistic cultures such as South Korea instead value group harmony and rule-following.
  • … By the 1960s and 1970s the highly individualistic world we know today had begun to emerge in many countries around the world: Personal choice was paramount, the U.S. military became an all-volunteer force, and “do your own thing” became a mantra. Sacrificing for the greater good was less prized. Treating people as individuals means setting aside the idea of group membership as destiny, which gave rise to movements for individual rights based on gender, race, and class, enshrining equality as a core value of the culture.
  • … Between 1980 and 2019, individualistic phrases promoting self-expression and positivity became steadily more common in the 25 million books scanned in by Google (p. 9-10)

I find these characterizations a bit vague. I wish she had put more effort into spelling out what she means by individualism.

I find it easiest to think in terms of the contrast between a small village and a contemporary urban existence. In a tight-knit community, everyone knows you. The people with whom you do business are the same people with whom you engage in recreation or see on the street, in church, or at a bar. Your conduct is constrained by the community’s norms and also by its expectations for you based on your past behavior. Until well into the Industrial Revolution, a boy often took on his father’s occupation (typically farming) and a girl took on her mother’s role (farmer’s wife or urban housewife).

In modern society, you have more degrees of freedom to shape yourself. Accordingly, people pay more conscious attention to choosing their occupations, their associates, their loyalties, their life partners, and their beliefs. I think of this when I see the term “individualism.”

For more on these topics, see “The Boys Under the Bus,” by Arnold Kling. Library of Economics and Liberty, Dec. 5, 2022.

With all of that said, let me list a few of the observations that I culled from Generations. Keep in mind that there are nuggets like these every few pages, and it is a 500+ page book, so this is only a tiny sampling.

  • While 7 in 10 women in their early 20s were married in 1960, only 1 in 10 was in 2020. Nearly half of men in their early 20s were married in 1960, but now only 1 in 14 are. (p. 376)
  • 85% of U.S. adults said that premarital sex was wrong in 1967, which plummeted to 37% in 1979. (p. 90)
  • Among Americans born in the 1990s, 1 out of 7 in their early 20s had not a sexual partner as an adult. (p. 289)
  • Social media also explains a unique feature of Millennial social movements: They are decentralized, without leaders, and focused on words and ideas rather than single concrete goals.2 (p. 256)
  • By 2019, households headed by Millennials actually made more money than Silents, Boomers, and Gen X’ers at the same age. (p. 260)
  • Every single penny of the rise in younger adults’ incomes is due to women’s incomes. (p. 272)
  • In late 2020 and early 2021, Gen Z was the only generation in which a majority believed there are more than two genders. (p. 350)
  • In many ways, 18-year-olds now look like 14-year-olds in previous generations…. only about half of 12th graders date, about the same as 8th graders in the early 1990s.3 (p. 374)
  • 4 out of 10 Gen Z’ers believe that the founders of the United States are “better described as villains” than “as heroes.” (p. 420)
  • There has also been a large increase in teen boys believing that women are discriminated against in getting a college education, from 18% in 2012 to 30% in 2019.4 (p. 427)


[1] Jean M. Twenge, Generations: The Real Differences Between Gen Z, Millennials, Gen X, Boomers, and Silents—and What They Mean for America’s Future. Atria Books, 2003.

[2] Martin Gurri, author of The Revolt of the Public, has emphasized this characteristic of recent social movements.

[3] On my Substack newsletter, I started writing that “17 is the new 15.” Apparently I understated the change.

[4] In fact, in recent years, the proportion of female college students has approached 60 percent. But the teen boys may nonetheless be correct, because in an attempt to achieve better gender balance, some schools do tilt the admission scales in favor of males.

*Arnold Kling has a Ph.D. in economics from the Massachusetts Institute of Technology. He is the author of several books, including Crisis of Abundance: Rethinking How We Pay for Health Care; Invisible Wealth: The Hidden Story of How Markets Work; Unchecked and Unbalanced: How the Discrepancy Between Knowledge and Power Caused the Financial Crisis and Threatens Democracy; and Specialization and Trade: A Re-introduction to Economics. He contributed to EconLog from January 2003 through August 2012.

Read more of what Arnold Kling’s been reading. For more book reviews and articles by Arnold Kling, see the Archive.

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