If you don’t immediately identify as Type A, you’re probably Type B. Or so I was told, after hesitating when my friend asked which category I belonged to.

Nowadays, most people flaunt a Type A personality as an indicator of being motivated and high-achieving. Type A is interchangeable with ambitious and competitive, if not high-strung and tense. A bit different than their modern uses, the terms “Type A” and “Type B” were originally coined by two cardiologists, Meyer Friedman and RH Rosenman, in the 1960’s to set apart patients who were at an increased risk of heart attacks and strokes due to high levels of stress. Type B, synonymous with laid-back and carefree, was actually the personality type most sought-after. Freidman and Rosenman’s research suggested that Type B personalities would ultimately find greater happiness and fulfillment in their lives.

These days, people like to suggest that being Type A is a requirement for reaching success in life. It means you’re the first to ask for a promotion and the last one to give up halfway through a project. It means you plan out your weeks by the hour and write detailed to-do lists. Type B people, on the other hand, have never owned a planner and are perfectly comfortable with a flooded inbox.

Is being highly-organized and detail-oriented absolutely crucial for success? Probably not… apparently science is now proving that chaos and clutter actually means you’re more intelligent and creative. And there’s always Albert Einstein who famously said, “If a cluttered desk is a sign of a cluttered mind, of what, then, is an empty desk a sign?”  

However, it’s more difficult to argue that you don’t need to be ambitious and a little high-strung to reach high levels of achievement. I polled another one of my friends to see if they identified as Type A or B, and they explained that they definitely aren’t Type A, but wouldn’t say they’re Type B either because “they’ve actually done things in their life.”  That brings us to the third, less well-known option: Type AB.

Freidman and Rosenman included the term Type AB for people that were too difficult to categorize into either extreme. Essentially, these were people that had some combination of the traits commonly associated with the two main types. In reality, most of us probably fall somewhere in the AB category, leaning slightly one way or the other. It’s unclear if these classifications actually mean anything at all, but despite being several decades outdated, they’re still heavily used today.

Contact Elizabeth Dunn at eldunn14 ‘at’ stanford.edu.