Researchers report an increase in individualistic words and phrases in American books published over the past half-century.

See Dick. See Dick look in the mirror. See Dick admire his reflection.

Researchers who have scanned books published over the past 50 years report an increasing use of words and phrases that reflect an ethos of self-absorption and self-satisfaction.

“Language in American books has become increasingly focused on the self and uniqueness in the decades since 1960,” a research team led by San Diego State University psychologist Jean Twengewrites in the online journal PLoS One. “We believe these data provide further evidence that American culture has become increasingly focused on individualistic concerns.”

Their results are consistent with those of a 2011 study which found that lyrics of best-selling pop songs have grown increasingly narcissistic since 1980. Twenge’s study encompasses a longer period of time—1960 through 2008—and a much larger set of data.

Using the Google Books Ngram viewer, the largest database of digitized books, she and her colleagues examined the contents of 766,513 books, looking for specific words and phrases that reflect either an individualistic or communal mindset. (Although the use of this dataset is somewhat controversial, Twenge defends it by noting that books reflect a society’s shared assumptions, and help “shape individuals’ ideas of cultural norms.”)

Panels recruited through the online service MTurk created lists of common words and phrases connoting either communalism or individualism. Based on their recommendations, the researchers set out to find such individualistic words and phrases as “independent,” “all about me,” “I am special” and “I get what I want,” along with such communal words and phrases as “teamwork,” “band together” and “common good.”

All of those words and phrases increased in usage over time, as the language evolved. After the researchers factored that into their analysis, they found only the individualistic words and phrases significantly increased from 1960 to 2008.

Interestingly, among the 20 individualistic words the researchers searched for, those that experienced the largest increase in usage were “identity,” “personalized,” “self,” “standout” and “unique.”

Consistent with this trend, “Many of the individualistic phrases, especially those that increased over time, included the word ‘self’ or emphasized uniqueness and/or being better than others,” the researchers write. Meanwhile, “Individualistic words and phrases emphasizing standing alone (such as independence, self-reliance, self-sufficient, solitary and sole) were among the few that decreased or did not change.”

If that all sounds depressing, it’s worth noting that Twenge and her colleagues urge caution in drawing conclusions from their data. There are many ways of uncovering such trends, they note, and this is just one of them.

What’s more, they point out that throughout the time period they studied, “communal words and phrases were more commonly used than the individualistic words and phrases.” So there’s some evidence that our culture hasn't turned completely narcissistic—yet.