Wednesday, September 11, 2019

Why is vocabulary shrinking?

Vocabulary decline in adult non-Hispanic White Americans (controlled for years of education completed)

"Are Americans more intelligent than a few decades ago, or less intelligent?" So asks psychologist Jean Twenge in her introduction to a recent paper on vocabulary decline in Americans. The findings are disconcerting, to say the least:

We examined trends over time in vocabulary, a key component of verbal intelligence, in the nationally representative General Social Survey of U.S. adults (n=29,912). Participants answered multiple-choice questions about the definitions of 10 specific words. When controlled for educational attainment, the vocabulary of the average U.S. adult declined between the mid-1970s and the 2010s. Vocabulary declined across all levels of educational attainment (less than high school, high school or 2-year college graduate, bachelor's or graduate degree), with the largest declines among those with a bachelor's or graduate degree. (Twenge et al. 2019)

The last decline was especially large: more than half a standard deviation. In general, vocabulary test scores have fallen by 8.5%. Ethnic change doesn’t seem responsible, since non-Hispanic whites have had almost the same decline: 7.2%.

So what's going on? The authors considered the explanation they first raised: Americans have become less intelligent despite the increase in education.

First, Americans' vocabularies might be shrinking despite the increase in education. This is plausible given the steep decline in the amount of time high school students spend reading [...] and the decline in SAT verbal scores over time [...]. This explanation could account for the narrowing of abilities between those without high school educations and those with college educations. The difference in vocabulary by education was approximately 3.4 correct answers in 1974-79 but dropped to 2.9 correct answers by 2010-16. However, this explanation would not account for the decline in performance in all educational groups. (Twenge et al. 2019)

Uh, why not? The last sentence makes sense if the explanation is simply that postsecondary education has become less effective. But what if vocabulary has declined because the capacity for learning words and retaining them has also declined? The cause may be genetic. Can we at least ask that question?

Lower admission standards? Mismatch between cause and effect

The authors then consider another explanation: because college admission standards have been lowered, people of lower ability have been going on to postsecondary education in larger numbers; those who don't are increasingly the least able.

If education does not improve vocabulary, but educational attainment increases, those with higher ability will be increasingly selected into the higher education groups, leaving those with lower ability in the lowest educational attainment groups. Thus, the no high school degree group will be left with those of lowest ability, and the college graduate group will have absorbed more with only moderate ability. (Twenge et al. 2019)

That explanation is popular, but it doesn’t really match the findings. The vocabulary decline was steepest during the late 1970s and early 1980s. It then levelled off. A second decline may have begun in 2008, but it’s still too early to say (see Figure 1 reproduced above). Most of the decline doesn't correspond to any previous change in college enrollment by recent high school graduates. The enrollment rate rose slowly from 45.7% in 1959 to 49.4% in 1980. It began to grow faster only in the mid-1980s, breaking through the 60% level in 1991 and the 70% level in 2009 (Bureau of Labor Statistics 2010).

So the alleged cause doesn’t match the presumed effect. The steep increase in college enrollment from the mid-1980s onward could not have caused the steep vocabulary decline during the late 1970s and early 1980s. Keep in mind that most of the GSS respondents had completed their education some years earlier, almost ten years earlier on average. So the average respondent in the late 1970s had to meet college admission standards that existed in the late 1960s.

Most of the decline has been among early boomers

Because the GSS was first administered in 1974, we don't know when the steep vocabulary decline began. But we do know when it ended: in the mid-1980s, among respondents who were born on average thirty years earlier. A genetic cause would imply a rapid deterioration in the gene pool from 1945 to 1955 and a slower deterioration thereafter. I have no idea what that cause could be.

If we're looking for a cultural cause, it would have acted most strongly on the same cohort of "early boomers." Perhaps it was their increasing exposure to TV and their decreasing exposure to high literature. Those cultural changes were already a fait accompli for "late boomers," who experienced a more gradual dumbing down of vocabulary on TV and in print. The post-2008 vocabulary decline, if it’s real, might reflect the growing importance of iPhone texting since the late 2000s.

That cultural explanation has some support from the data and is favorably mentioned by the authors. For one thing, comparison with the results of another test (WAIS) suggests that the decline has been mostly in passive vocabulary, i.e., the words we understand but don’t use spontaneously in speech (Twenge et al. 2019). We’re less proficient in "bookish" language:

Perhaps American culture became less intellectual, either because of or in response to a lowering of verbal ability among those who read books. Authors aim to sell more copies of their books, and thus may adjust their vocabulary level to the skills and preferences of a wider slice of the population. Or, perhaps authors lowered the vocabulary level of their books for some other reason such as an interest in getting out a message without linguistic complexity getting in the way. For example, the Bible has been revised repeatedly to make it more accessible with the King James Version, the most complex and lyrical English language version, being succeeded by the simpler New International Version, Living Bible, and New Revised Standard Version. (Twenge et al. 2019)

The last point rings true. When I was studying Shakespeare in high school my mother could explain words I had trouble understanding. She had never gone beyond Grade 10, but she could read the Bible in the King James Version, as well as a lot of high-brow literature. This was true for many ordinary adults in the 1970s. Today, regular reading of the Bible is unusual and almost always confined to modern English versions.


Yes, college has become a less interesting place for learning vocabulary, and for learning in general. Yes, a big reason is the growing number of students who don’t really belong there, and the consequent lowering of standards. Yes, America’s cultural and linguistic mix is changing, and for that reason alone the average American would have a smaller English vocabulary.

Nonetheless, those factors fail to explain why non-Hispanic white Americans know fewer words today than they did a half-century ago, especially in their passive vocabulary. Something else is going on, and it seems to be a shift away from high literature and toward simpler audiovisual media: TV, video, text messaging …


Bureau of Labor Statistics. (2010). College enrollment up among 2009 high school grads. TED: The Economics Daily. April 28

Twenge, J.M., W.K. Campbell, and R.A. Sherman. (2019). Declines in vocabulary among American adults within levels of educational attainment, 1974-2016. Intelligence 76: 101377

12 comments: said...

WW2 has something to do with it.

Maybe some Veterans Preference Act?
Maybe the best men were killed?

Maybe it was moving from books and radio to TV (more visual memory against uditive memory).

If it stopped during the 1980s, it is when computer become mainstream and people started to learn to read and write to use PCs, write code, etc.

How the diet changes after the war and after the 1980s?

Anonymous said...

If you read articles or books from the 1950s or 1960s, you marvel at how educated and sophisticated the language was at that time compared to now. And the farther back you go in history, the more that was the case. People like Lincoln and other Americans in the 1850s spoke a language even more refined, precise, and highly sophisticated than in the years that followed. But even as recently as the 1950s and 60s, Americans weren't blurring the now-defunct distinction between "who" and "whom," for instance, and words like "encroach" or "ubiquitous" were widely known and used. Actually, right now we're in the middle of even further simplification, as linguistic forms like "Because [noun]" (such as "because socialism") are starting to become common.

The farther back you go in history, the more complicated the English language was (and many others as well). In prior centuries it had a complex case-declension system similar to today's Slavic languages, which it has since lost. The word "you" was distinguished from "thou" by meaning. In contrast to just 2 cases (main and possessive) it had many more. There were multiple genders, and nouns had functions.

Don't forget about the Flynn effect - the idea that the human IQ is declining, because intelligent people aren't selected for sexually as they were in the past.

Anonymous said...

This accords with my experience. I grew up in the 90s, when the internet was just becoming widely available. My parents were slow to get the internet at home, and when we did get it, it was very slow dial-up internet. And we did not have cable TV. There was basically nothing to do at home, and the only way to satisfy one's intellectual curiosity was to read the books my parents had and to checkout books from the library. So I ended up reading books constantly. I'd read the print newspaper every morning, and political and other magazines when they came every month, but there wasn't a steady stream of short articles coming out constantly like there is today with the internet. You had to turn to long books for reading material.

Nowadays, there is lots of intellectual content online through social media, blogs, articles, videos, podcasts, etc., along with more entertainment options available online and through streaming. I find myself reading books a lot less than I used to, and would otherwise if there wasn't this competition for attention from the internet. Furthermore, I find myself more easily distracted when reading books. It was much easier before the internet and smartphones for me to plow through hundreds of pages in a book in one sitting with no problems or distraction. Nowadays, I get more distracted and have an urge to check the internet for news, new articles, etc.

I'm still a big reader of books compared to most people, so I imagine the average person who was never a big reader basically doesn't read books at all anymore with all these other options now available.

tomR said...

Today we have much more words overall than years ago. Most of these are names of products, names of corporations, names of technologies etc. There is also much more acronyms which for the purposes of human memory count the same as just another word. If overall human capacity for words is fixed, and people have to include all those new names, then these new names crowd out classic words from our minds.

Anonymous said...

Off topic:

Peter, what is your view of George Grant? I only learned about him and his book "Lament for a Nation" recently, and he sounds like an intriguing figure. I'm an American, and I've always been interested in 20th century Canadian history, particularly its rapid transition from a relatively conservative, culturally British Protestant country loyal to the Crown to a sort of artificial independent nation and now to a state that's at the vanguard of modern liberal, multiculturalist ideology. I know very little about this history as it's not something you learn in school or find books about or hear discussed in the US. I'm also interested in Quebec's similar transformation from a rural, conservative, clerical, Catholic nation to a secular leftist nationalist one seemingly overnight.

Grant seems very interesting because of his conservative anti-Americanism, nationalism, skepticism of capitalism, "Red Toryism". It's hard to believe a figure with such views was prominent as recently as the 80s since conservatives in Canada and the US are nothing like that these days. "Lament for a Nation" sounds very interesting because from what I understand, Grant's thesis in the book is that Canada was traditionally conservative and much less liberal, whereas most people today assume that Canada was always a hyper liberal place at the vanguard like it is today.

Peter Frost said...


I'm not hostile to genetic explanations, but the vocabulary decline of the late 1970s / early 1980s seems too rapid to be due to genetic change. The cause would have to be about thirty years earlier, during the time of the early boomers. Early boomers began to read during the 1950s, and that would be the time frame when TV began displacing books as a form of entertainment for kids. I remember reading a lot of adult books when I was only 7 (mainly about astronomy and popular science), but that was already unusual. I just didn't find the stuff on TV all that interesting.


There is a lot of evidence that mean IQ peaked in Victorian times and has since declined (mean reaction time and polygenic scores). See:

That decline has been masked by the Flynn Effect, which doesn't seem to be a real increase in intelligence. People have simply become more familiar with test taking. In any case, the Flynn Effect seems to be reversing.


Yes, I read fewer books now. More and more books seem to be written to meet certain standards of political orthodoxy. The content has also been noticeably dumbed down: sentences are shorter and less complex, and the vocabulary is simpler. I limit the time I spend watching videos on the Internet because I find that kind of content leaves less time for serious reading.


Perhaps, but my impression is that acronyms and product names were just as ubiquitous in the 1970s. Do you really think we have more of them now?


I actually attended an informal lecture by George Parkin Grant in 1979. We were in a small room at the University of Toronto, and only twenty or so people were in attendance. He was strongly influenced by Heidegger, and I remember him saying that he felt that Heidegger was wrong in his association with the Nazi movement but was essentially right in his ideas. He then surprised us by saying that only three social systems are possible: liberal capitalism, international socialism, and national socialism. He had a look on his face as if he were speaking reluctantly and expecting a strong reaction from us. But none of us said anything in disagreement.

If he were alive today, he would be a pariah. The bounds of acceptable discourse are much more limited today than they were in the late 1970s. This might be a factor in the recent vocabulary decline (post 2008). Many words have been more or less banned.

Anonymous said...


Do you think Grant's claims about Canada's ideological evolution were accurate? Namely that Canada was fundamentally a conservative society that gradually succumbed to the American empire and imposed a top-down liberal revolution on society.

Peter Frost said...


Yes, Canada was created as a kind of Anti-America, a society where notions of radical individualism and radical egalitarianism would not hold sway. That experiment failed for several reasons:

- Social conservatism leads to slower economic growth and less innovation. Even in the 19th century, we were painfully conscious of being economic and cultural laggards compared to the Americans.

- Our mother country (i.e., the United Kingdom) was drained of her demographic and financial resources by the First World War and then the Second World War. The United States, which was a latecomer to both wars, emerged as the real victor. With the onset of the Cold War, Canada was encouraged to form a stronger relationship with the U.S.

- Americanization was strong during the postwar era. The U.S. became our political, economic, and cultural model, and this trend became even stronger with the collapse of the British Empire. By the mid-1960s there really was no British Empire. We had to redefine ourselves, and this redefinition was led by Americanized elites who wanted to be better at what the Americans were doing. Our "anti-Americanism" is really a kind of hyper-Americanism.

Passer by said...

There was no decline in overall vocabulary scores of the white population. Only in the education adjusted category, but since more people are educated than before, these effects canceled out.

So according to the study, white americans are as smart as those from the past, vocabulary wise.

Also declining SAT scores does not mean anything, considering the fact that more and more people (and therefore more dumber people) take the SAT. When you test the whole population on the SAT, (some states have done that) mean scores are even lower.

So whether americans are getting dumber - hard to say. Some data backs this up (PISA data). Some data does not. What is clear though, is that the Flynn Effect is over in western countries. Westerners are not getting smarter anymore. They stay at the same level. Including whites.

Peter Frost said...

Passer by,

All things being equal, education should increase your vocabulary. That's why the authors controlled for years of education. University graduates today have a much smaller vocabulary than they did a half-century ago. Same goes for high school graduates, and people with no education. If you compare apples with apples, there has been a real decline in vocabulary.

I'm not saying that non-Hispanic white Americans are less smart today than they were in the past. Nor are the authors of the study. If we look at data from Iceland, we see that the genetic capacity for intelligence (polygenic score) has been declining over the past century. That decline has been more than offset by the Flynn Effect, but the Flynn Effect doesn't seem to be a real increase in intelligence. We're just getting more familiar with tests and adopting the right strategies for test taking (like not spending too much time on really tough questions).

Santo said...

Excesses of synonymous is great for poetry, help it a lot, BUT... not so about for what language exist, to comunicate effectively and to subtitle facts or real things.. In the time of conservative cultural over-predominance the frivolity of pompous words were used to signalize elitism, specially from cultural elites and it's still there, with many grammar queens pumps in the internet.

''If we look at data from Iceland''

I would be analyse it in Iceland and also take more information about families, what are the families which suffered more decline of these ''polygene score''.

Steve said...

C Section births and the onslaught of vaccines given to the early boomers would account a lot for this . Vaccines increase levels of pathogens and yeasts in the human intestinal tract. I'm a natural healer and fasting due to my own compromised gut flora thanks to my baby boom mother who was the first "successfully" given the polio vaccine (which i consider toxic and unnecessary). I also reacted to my own MMR vaccine and not being breast fed.