Can the pronouns you use reveal your personality?  According to James Pennebaker, Chair of Psychology at the University of Texas at Austin, they can.

After analyzing 400,000 texts – including essays, instant messages, chat rooms and press conferences – he concluded that function words are important keys to someone’s psychological state and reveal much more than content words do.  From the Harvard Business Review Article:

HBR: Why are function words so important?

In English there are about 500 function words, and about 150 are really common. Content words—nouns, verbs, adjectives, and most adverbs—convey the guts of communication. They’re how we express ideas. Function words help shape and shortcut language. People require social skills to use and understand function words, and they’re processed in the brain differently. They are the key to understanding relationships between speakers, objects, and other people. When we analyze people’s use of function words, we can get a sense of their emotional state and personality, and their age and social class.

Here’s a simple, pronoun-heavy sentence: I don’t think I buy it.

Ooh. You just revealed something about yourself in that statement. Why did you say “I don’t think I buy it” instead of “I don’t buy it” or even “That’s ridiculous”? Pronouns tell us where people focus their attention. If someone uses the pronoun “I,” it’s a sign of self-focus. Say someone asks “What’s the weather outside?” You could answer “It’s hot” or “I think it’s hot.” The “I think” may seem insignificant, but it’s quite meaningful. It shows you’re more focused on yourself. Depressed people use the word “I” much more often than emotionally stable people. People who are lower in status use “I” much more frequently.

To find out more about how your use of pronouns is a tell for your personality, visit the full article on here on the Harvard Business Review website.