Editor's note: The following is an excerpt from "The Road Back to You: An Enneagram Journey to Self-Discovery."

Neuroscientists have determined the brain’s dorsolateral prefrontal cortex is associated with decision making and cost-benefit assessments. If MRI brain scans had been performed on my friends and me one summer’s night when we were fifteen, they would have revealed a dark spot indicating a complete absence of activity in this region of our brains.

That particular Saturday night a group of us got the brilliant idea that streaking a golf banquet at an exclusive country club in my hometown of Greenwich, Connecticut, was a wise decision.

Other than certain arrest for indecent exposure, there was only one problem: Greenwich isn’t a big town, and it was likely someone we knew would recognize us.

After several minutes of deliberation we decided upon ski masks, and so at roughly 9:00 p.m. on a warm August night, six naked boys in ski masks sprinted through a room full of bankers and heiresses. The men clapped and cheered for us while the women sat frozen in shock. We had hoped for the opposite reaction, but there was not ample time to stop and express our disappointment.

And that would have been the end of it if it weren’t for my mother.“What did you and the guys do last night?” she asked the next morning. “Not much. We hung out at Mike’s, then crashed around midnight.”

I instantly had an uneasy feeling. “What did you and Dad do last night?” I said brightly. “We went as guests of the Dorfmanns to their club’s golf banquet,” she replied in a tone that was one part sugar, one part steel.

The purpose of the Enneagram is self-understanding and growing beyond the self-defeating dimensions of our personality, as well as improving relationships and growing in compassion for others.

“A ski mask?” she demanded, her voice rising. “A ski mask?” The tip of her nose was no more than an inch from my own. “I could pick your scrawny butt out of a lineup in the dark,” she whispered menacingly.

I tensed, wondering what was coming next, but the storm passed as abruptly as it rolled in. My mother’s face relaxed into a sly grin. She turned on her heels and said over her shoulder as she walked out of the kitchen, “You’re lucky your father thought it was funny.”

This was not the first time I wore a mask to protect myself—far from it.

Human beings are wired for survival. As little kids we instinctually place a mask called personality over parts of our authentic self to protect us from harm and make our way in the world.

Made up of innate qualities, coping strategies, conditioned reflexes and defense mechanisms, among lots of other things, our personality helps us know and do what we sense is required to please our parents, to fit in and relate well to our friends, to satisfy the expectations of our culture and to get our basic needs met.

Over time our adaptive strategies become increasingly complex. They get triggered so predictably, so often and so automatically that we can’t tell where they end and our true natures begin.

Worst of all, by overidentifying who we are with our personality we forget or lose touch with our authentic self—the beautiful essence of who we are.

The goal of understanding your Enneagram “type” or “number” is not to delete and replace your personality with a new one. Not only is this not possible, it would be a bad idea.

You need a personality or you won’t get asked to prom. The purpose of the Enneagram is self-understanding and growing beyond the self-defeating dimensions of our personality, as well as improving relationships and growing in compassion for others.

The Enneagram teaches that there are nine different personality styles in the world, one of which we naturally gravitate toward and adopt in childhood to cope and feel safe. Each type or number has a distinct way of seeing the world and an underlying motivation that powerfully influences how that type thinks, feels and behaves.

If you’re like I was, you will immediately object to the suggestion that there are only nine basic personality types on a planet of more than seven billion people.

A single visit to the paint aisle at Home Depot to help an indecisive spouse find “that perfect red” for the bathroom walls might quell your remonstrations.

There are literally an infinite number of variations of the color red from which you can select to brighten your bathroom and wreck your marriage at the same time.

In the same way, though we all adopt one (and only one) of these types in childhood, there are an infinite number of expressions of each number, some of which might present in a similar way to yours and many of which will look nothing like you on the exterior—but you are all still variations of the same primary color. So don’t worry, Mom didn’t lie. You are still her special little snowflake.

Here are the names and a quick description of each Enneagram number. For the record, no personality type is better or worse than another, each has its own strengths and weaknesses, and none is gender-biased.

TYPE ONE: The Perfectionist. Ethical, dedicated and reliable, they are motivated by a desire to live the right way, improve the world, and avoid fault and blame.

TYPE TWO: The Helper. Warm, caring and giving, they are motivated by a need to be loved and needed, and to avoid acknowledging their own needs.

TYPE THREE: The Performer. Success-oriented, image-conscious and wired for productivity, they are motivated by a need to be (or appear to be) successful and to avoid failure.

TYPE FOUR: The Romantic. Creative, sensitive and moody, they are motivated by a need to be understood, experience their oversized feelings and avoid being ordinary.

TYPE FIVE: The Investigator. Analytical, detached and private, they are motivated by a need to gain knowledge, conserve energy and avoid relying on others.

TYPE SIX: The Loyalist. Committed, practical and witty, they are worst-case-scenario thinkers who are motivated by fear and the need for security.

TYPE SEVEN: The Enthusiast. Fun, spontaneous and adventurous, they are motivated by a need to be happy, to plan stimulating experiences and to avoid pain.

TYPE EIGHT: The Challenger. Commanding, intense and confrontational, they are motivated by a need to be strong and avoid feeling weak or vulnerable.

TYPE NINE: The Peacemaker. Pleasant, laid back and accommodating, they are motivated by a need to keep the peace, merge with others and avoid conflict.

Maybe now you’re starting to get an idea of which of the nine types you belong to (or which one explains your seventy-year-old uncle who still dresses up like Yoda and attends Star Wars conventions). But the Enneagram is more than a list of clever type names. That’s just the beginning of the journey, one that can spark greater compassion for others and for yourself. Such compassion is the foundation of relationships. It changes everything.

Adapted from The Road Back to You by Ian Morgan Cron and Suzanne Stabile. Copyright © 2016 by Ian Morgan Cron. Used by permission of InterVarsity Press, P.O. Box 1400, Downers Grove, IL 60515, USA. www.ivpress.com.