Know Yourself: An Introduction to Psychometrics

Get to know yourself and become a better human being. Do you find it hard to get up on time in the morning, connect well with people, but your relationship is a mess. What’s the deal? In this post, we’re going to talk about psychometrics, both so that you can better understand and know yourself, and those around you—and most importantly, understand what you can and cannot change.

A Brief History of Personality Types

If you’re a parent, then you already know a something about classic personality types: colic, coined by Galen, is the ancient Greek  word for intestine (Solter, 1998), and causes babies to cry for three or more hours per day, for weeks on end. Humorism, or the belief that there were four bodily “humors” that determined personality type (êthos), originated in ancient Greece with Hippocrates—that’s right, the same guy who came up with the “first, do no harm” credo in medicine—and Galen (Bos, 2009). They suggested that a person’s êthos could be phlegmatic, or apathetic; choleric, or aggressive; sanguine, or enthusiastic and social; and melancholic, or depressed (Jackson, 2001; Merenda, 1987). There were various treatments, such as bloodletting, to treat the different conditions, and they were popular up into the 18th and 19th century, but as they were more based on philosophy than anything else, you don’t hear these terms being used much these days.

Next, we have the still popular Myers-Briggs Type Indicator, or MBTI for short. Are you an introvert or an extravert? INTJ or ENTP? The MBTI was based on Carl Jung’s Psychological Types (Jung, 1976), and was one of the first attempts at psychometrics, or the measuring of personality. However, while it was based on Jung’s work (Myers & Myers, 1995), neither Briggs, nor Myers, had any training in psychology. Furthermore, when checked using factor analysis, the results don’t match up like Myers or Briggs said that they would (Cooper, 2010), i.e., the test didn’t test for what they thought it tests. As someone who is himself studying Jung, to be clear, Jung’s model is good, and terms like introvert and extravert are legitimate—we’ll talk about that in another post—it’s just that MBTI isn’t Jung’s model, and it just doesn’t hold up under scientific scrutiny

So humours are out, MBTI is out, what’s left? Grab your swim trunks, because we’re about to dive into OCEAN.

OCEAN: The Big Five Personality Traits

Let’s talk about language: what are the basic adjectives we use to describe people’s personalities? Are they long and complicated phrases, or, more often than not, short and simple words? Enter the lexical hypothesis (Ashton & Lee, 2005), which states that, in any language:

a) important descriptions of people find their way into a language;

b) those descriptions are usually single words.

Think about how you would describe your best friend or worst enemy—you might have a lot of things to say, but most of it is probably some variation of a basic idea, and that idea can probably be summed up in one word.

The Five Factor Personality Traits were discovered in the 1980s using the lexical hypothesis and factor analysis(Goldberg, 1990)—IQ was discovered using factor analysis, too, by the way—which means that when participant questionnaires were analyzed, certain answers “clumped” together, i.e., showed that they were related and reproducible. Psychologists reviewed these five factors, and gave them the acronym OCEAN (DeYoung et al., 2007; Goldberg, 1993), which stands for openness, or openness to experience and intellect; conscientiousness, or industriousness and orderliness; extraversion, or enthusiasm and assertiveness; agreeableness, or compassion and politeness; and neuroticism, or volatility and withdrawal.

This test, and its close cousin, HEXACO, are the best, basic, and scientifically proven ways to begin to understand yourself and others; furthermore, the results have replicated across cultures and languages (McCrae et al., 1998; McCrae & Allik, 2002; Poortinga et al., 2002), and even gender differences in results are more or less stable (Weisberg et al., 2011).

Now, before reading further (if you have time! The test is long, and has 300 questions), take the Five Factor test here—this is the best, free, version that I’ve found, and I trust its results; we looked at this specific iteration in my psychology MSc. Get your partner, your parents, or friends to take it, and compare the results. Make sense? Be forewarned, though, this is not a feel-good test—some of these results might reveal things about you that you would rather not know—your shadow—but we’ll talk about that, too, when we talk about Jungian psychology in another post. Once you’ve checked out your results, keep reading.

Keys To Success: Me, Myself, and I

Now some of you are really proud of yourselves and some of you might be very upset. High in conscientiousness! I’m a boss! Or, oh no, high in neuroticism! I’m a mess! Well, the good news is, while these traits are partially hereditary, just like IQ, they’re also partially the result of your environment (Polderman et al., 2015; Power & Pluess, 2015) and that means you can change them. How much? A recent study says that it depends (Hudson & Fraley, 2015; Vitelli, 2015), but let’s say a 30% change is possible with some effort. Here’s why this matters.

Work and success in life. Other than IQ, conscientiousness is one of the primary predictors of success in life, including academics, professional life, health, and so on (Bogg & Roberts, 2004; A. L. Duckworth & Seligman, 2005; Dudley et al., 2006). And for those in the military, or aspiring to the military, it is often the defining factor (McCormack & Mellor, 2002). The good news is that, of all the Big Five Traits, conscientiousness, sometimes called grit, is somewhat more flexible and trainable than the other traits (A. Duckworth, 2016; Javaras et al., 2019; Reed et al., 2013). How? Through making small, incremental changes in your habits, or even taking part in CBT, cognitive behavioral therapy; in essence, upping your consciousness of what you’re doing, and setting small goals that you can 100% succeed in, e.g., “I will do five pushups every day.” Then, once this becomes habit, you can add incrementally to it. Remember, slow is fast, and don’t bite off more than you can chew.

Other than IQ, conscientiousness is one of the primary predictors of success in life, including academics, professional life, health, and so on.

But what about relationships? We know that we find people who are similar to be attractive (Montoya et al., 2008), and that actually being similar helps to have a successful relationships (Gonzaga et al., 2007)—specifically, “Actual similarity was positively associated with female relationship satisfaction” (Decuyper et al., 2012). However, as Carl Jung writes, the biggest problem in our relationships is believing that your partner is just like you, i.e., that if your partner is messy, then it’s because he or she just aren’t trying hard enough, or are doing so to piss you off (Jung, 2015). If couples get divorced, it usually happens in or around the 4-5 year mark (Carrère et al., 2000; Markman et al., 2010)—just enough time for those projections about who your partner is to fade into disappointment. But if you can be in a relationship with your eyes open, say, through a tool like the Big Five, then you can consciously let go of those early projections and accept our partner for who they are, while at the same time making it your common project to work together on that 10-30% that can be shifted. “She’s high in conscientiousness and I’m not, but I’m high in openness—OK, so I need to remember that work and orderliness are more important to her than to me, and I also need to communicate how it’s important to me to not be stuck in a rut, and to be doing new things. If we talk about this, we can do this.”

..the biggest problem in our relationships is believing that your partner is just like you, i.e., that if your partner is messy, then it’s because he or she just aren’t trying hard enough, or are doing so to piss you off.


There are many ways to get to know yourself, but not all of them are equally reliable. While nobody these days really talks about the humours, lots of people still turn to MBTI as their go-to personality test. Don’t do it—use the Big Five or HEXACO—we’ll talk about more advanced personality type analysis in a future post.

Once you know yourself, you can set yourself up for success in both the workplace, and in relationships, by working on your conscientiousness, and understanding that your partner actually isn’t exactly like you, and that that’s OK; hopefully, they’ll come to the same conclusion about you.

If you’re curious how all this can fit within the warfighter or veteran context from the male perspective, have read and listen to Dave’s conversation with Jonny Collins about, How To Be A Dangerous Man.

Unless there are specific requests from you, dear readers, then the next post will likely be about epigenetics and memetics, or how everything you do actually matters. All the papers and books mentioned in this post can be found below. Until next time, don’t forget: spectemur agendo.

This is Danny, signing off.

Danny is an ex-infanteer from Toronto who is now living in Eastern Europe with his son. He teaches English to grades 6-7-8-9 students, is finishing his MSc. in Psychology, and plans to start training as a Jungian Analyst next year.


Ashton, M. C., & Lee, K. (2005). A defence of the lexical approach to the study of personality structure. European Journal of Personality, 19(1), 5–24. https://doi.org/10/cb6mxj

Bogg, T., & Roberts, B. W. (2004). Conscientiousness and health-related behaviors: A meta-analysis of the leading behavioral contributors to mortality. Psychological Bulletin, 130(6), 887–919. https://doi.org/10.1037/0033-2909.130.6.887

Bos, J. (2009). The rise and decline of character: Humoral psychology in ancient and early modern medical theory. History of the Human Sciences, 22(3), 29–50. https://doi.org/10.1177/0952695109104422

Carrère, S., Buehlman, K. T., Gottman, J. M., Coan, J. A., & Ruckstuhl, L. (2000). Predicting marital stability and divorce in newlywed couples. Journal of Family Psychology, 14(1), 42–58. https://doi.org/10.1037/0893-3200.14.1.42

Cooper, C. (2010). Individual differences and personality (Third edition). Hodder Education.

Decuyper, M., Bolle, M. D., & Fruyt, F. D. (2012). Personality similarity, perceptual accuracy, and relationship satisfaction in dating and married couples. Personal Relationships, 19(1), 128–145. https://doi.org/10.1111/j.1475-6811.2010.01344.x

DeYoung, C. G., Quilty, L. C., & Peterson, J. B. (2007). Between facets and domains: 10 aspects of the Big Five. Journal of Personality and Social Psychology, 93(5), 880–896. https://doi.org/10.1037/0022-3514.93.5.880

Duckworth, A. (2016). Grit: The power of passion and perseverance (First Scribner hardcover edition). Scribner.

Duckworth, A. L., & Seligman, M. E. P. (2005). Self-discipline outdoes IQ in predicting academic performance of adolescents. Psychological Science, 16(12), 939–944. https://doi.org/10.1111/j.1467-9280.2005.01641.x

Dudley, N. M., Orvis, K. A., Lebiecki, J. E., & Cortina, J. M. (2006). A meta-analytic investigation of conscientiousness in the prediction of job performance: Examining the intercorrelations and the incremental validity of narrow traits. Journal of Applied Psychology, 91(1), 40–57. https://doi.org/10/drp97f

Goldberg, L. R. (1990). An alternative ‘description of personality’: The Big-Five factor structure. Journal of Personality and Social Psychology, 59(6), 1216–1229. https://doi.org/10.1037/0022-3514.59.6.1216

Goldberg, L. R. (1993). The structure of phenotypic personality traits. American Psychologist, 48(1), 26–34. https://doi.org/10.1037/0003-066X.48.1.26

Gonzaga, G. C., Campos, B., & Bradbury, T. (2007). Similarity, convergence, and relationship satisfaction in dating and married couples. Journal of Personality and Social Psychology, 93(1), 34–48. https://doi.org/10.1037/0022-3514.93.1.34

Hudson, N. W., & Fraley, R. C. (2015). Volitional personality trait change: Can people choose to change their personality traits? Journal of Personality and Social Psychology, 109(3), 490–507. https://doi.org/10.1037/pspp0000021

Jackson, W. A. (2001). A short guide to humoral medicine. Trends in Pharmacological Sciences, 22(9), 487–489. https://doi.org/10.1016/s0165-6147(00)01804-6

Javaras, K. N., Williams, M., & Baskin-Sommers, A. R. (2019). Psychological interventions potentially useful for increasing conscientiousness. Personality Disorders: Theory, Research, and Treatment, 10(1), 13–24. https://doi.org/10.1037/per0000267

Jung, C. G. (1976). Psychological Types (R. F. C. Hull, Ed.; H. G. Baynes, Trans.). Princeton University Press.

Jung, C. G. (2015). The practice of psychotherapy. In H. Read, M. Fordham, & G. Adler (Eds.), The collected works: Volume I-XX (Vol. 16). Routledge. http://search.ebscohost.com/login.aspx?direct=true&scope=site&db=nlebk&db=nlabk&AN=991955

Markman, H. J., Rhoades, G. K., Stanley, S. M., Ragan, E. P., & Whitton, S. W. (2010). The premarital communication roots of marital distress and divorce: The first five years of marriage. Journal of Family Psychology, 24(3), 289–298. https://doi.org/10.1037/a0019481

McCormack, L., & Mellor, D. (2002). The role of personality in leadership: An application of the five-factor model in the australian military. Military Psychology, 14(3), 179–197. https://doi.org/10.1207/S15327876MP1403_1

McCrae, R. R., & Allik, I. (Eds.). (2002). The five-factor model of personality across cultures. Kluwer Academic/Plenum Publishers.

McCrae, R. R., Costa, P. T., Del Pilar, G. H., Rolland, J.-P., & Parker, W. D. (1998). Cross-cultural assessment of the five-factor model: The revised NEO personality inventory. Journal of Cross-Cultural Psychology, 29(1), 171–188. https://doi.org/10.1177/0022022198291009

Merenda, P. F. (1987). Toward a four-factor theory of temperament and/or personality. Journal of Personality Assessment, 51(3), 367–374. https://doi.org/10.1207/s15327752jpa5103_4

Montoya, R. M., Horton, R. S., & Kirchner, J. (2008). Is actual similarity necessary for attraction? A meta-analysis of actual and perceived similarity. Journal of Social and Personal Relationships, 25(6), 889–922. https://doi.org/10.1177/0265407508096700

Myers, I. B., & Myers, P. B. (1995). Gifts differing: Understanding personality type. Davies-Black.

Polderman, T. J. C., Benyamin, B., de Leeuw, C. A., Sullivan, P. F., van Bochoven, A., Visscher, P. M., & Posthuma, D. (2015). Meta-analysis of the heritability of human traits based on fifty years of twin studies. Nature Genetics, 47(7), 702–709. https://doi.org/10.1038/ng.3285

Poortinga, Y. H., Van De Vijver, F. J. R., & Van Hemert, D. A. (2002). Cross-cultural equivalence of the big five. In R. R. McCrae & J. Allik (Eds.), The five-factor model of personality across cultures (pp. 281–302). Springer US. https://doi.org/10.1007/978-1-4615-0763-5_14

Power, R. A., & Pluess, M. (2015). Heritability estimates of the Big Five personality traits based on common genetic variants. Translational Psychiatry, 5(7), e604–e604. https://doi.org/10/f7qn3d

Reed, J., Pritschet, B. L., & Cutton, D. M. (2013). Grit, conscientiousness, and the transtheoretical model of change for exercise behavior. Journal of Health Psychology, 18(5), 612–619. https://doi.org/10.1177/1359105312451866

Solter, A. J. (1998). Tears and tantrums: What to do when babies and children cry. Shining Star Press.

Vitelli, R. (2015, September 15). Can you change your personality? Psychology Today. https://www.psychologytoday.com/blog/media-spotlight/201509/can-you-change-your-personality

Weisberg, Y. J., DeYoung, C. G., & Hirsh, J. B. (2011). Gender differences in personality across the ten aspects of the big five. Frontiers in Psychology, 2. https://doi.org/10/ddwz79

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