EVANSTON, Ill. --- Northwestern University researchers have sifted through data from more than 1.5 million questionnaire respondents and found at least four distinct clusters of personality types ...

The Greek physician Hippocrates argued that four bodily “humors” shaped human behavior, which, in turn, resulted in four fundamental personality types. Today, people put more faith in Myers-Briggs ...

People love taking personality tests, but are personality types real? Maybe, and maybe not. Personality development is complicated, and most healthy personality types are not so easily defined. Your ...

People love taking online quizzes; just ask Buzzfeed and Facebook. A new study has sifted through some of the largest online data sets of personality quizzes and identified four distinct “types” ...