In the six studies they’ve published so far, they’ve found that, for example, introverts make heavy use of emoticons and words related to anime, but extroverts say “party,” “baby,” and “ya.”

Words Used by Introverts (top) vs. Extroverts

Schwartz and his colleagues have also tracked “openness,” which is “characterized by traits such as being intelligent, analytical, reflective, curious, imaginative, creative, and sophisticated.” Open people talk about “dreams” and the “universe,” apparently, while people with “low openness”—“characterized by traits such as being unintelligent, unanalytical, unreflective, uninquisitive, unimaginative, uncreative, and unsophisticated”—use contractions, misspellings ... and misspelled contractions.

Openness (top) and Non-Openness Word Correlations

They’ve also analyzed how our use of certain words changes as we age. People are much less likely to be “bored” at 60 than at 13, it turns out, but much more likely to feel proud. Twenty-five year olds tend to mention “drunk,” but 55-year-olds talk about “wine.”

In one of the first studies, the team correlated past Gallup research on life satisfaction with tweets from various counties.

Happy communities, they found, talk about exercise—fitness, Zumba, and the gym—while the sadder ones felt “bored” or “tired.” The more upbeat locales were also more likely to donate money and volunteer, but also to go to meetings. The hidden socio-economic variable is clear: Having money allows you to go rock-climbing, give to charity, and it makes you happier, too.

So far, many of the findings have been rather predictable—which isn’t a bad thing, when it comes to social science.

“Subjects living in high elevations talk about the mountains,” they write. “Neurotic people disproportionately use the phrase ‘sick of’ and the word ‘depressed.’”

But some have shed light on a strange connections between who we are, how we live our lives, and the words we choose to present to the world. For example, “an active life implies emotional stability,” they note. And, “males use the possessive ‘my’ when mentioning their wife or girlfriend more often than females use ‘my’ with ‘husband’ or ‘boyfriend.’”

“It is a very unbiased view of humanity,” Schwartz said of the lab’s work so far. “The data tells the story, and it tells it about people.”