Over 100 years ago Charles Spearman made two monumental discoveries about human intelligence. First, a general factor of intelligence (g) exists: people who score high on one test of intelligence also tend to score high on other tests of intelligence. Second, Spearman found that the g-factor conforms to the principle of the "indifference of the indicator": It doesn't matter what test of intelligence you administer; as long as the intelligence test is sufficiently cognitively complex and has enough items, you can reliably and validly measure a person's general cognitive ability.

Fast forward to 2018, and a hot-off-the-press paper suggests that the very same principle may not only apply to human cognitive abilities, but also to human malevolence. New research conducted by a team from Germany and Denmark suggests that a General Dark Factor of Personality (D-factor) exists among the human population, and that this factor conforms to the principle of indifference of the indicator. This is big news, so let's take a look.

The Proposed D-Factor

We all know people who consistently display ethically, morally, and socially questionable behavior in everyday life. Personality psychologists refer to these characteristics among a subclinical population as "dark traits." An understanding of dark traits has become increasingly popular not only in psychology, but also in criminology and behavioral economics.

Even though psychologists have studied various dark traits, it has become increasingly clear that these dark traits are related to each other. This raises the question: Is there a unifying theme among dark traits?

Morten Moshagen and his colleagues proposed that a D-factor exists, which they define as the basic tendency to maximize one's own utility at the expense of others, accompanied by beliefs that serve as justifications for one's malevolent behaviors. In their definition, utility refers to goal achievement. For those scoring high on the D-factor, utility maximization is sought despite running contrary to the interests of others or even for the sake of bringing about negative outcomes in others.

Utility in this definition does not refer to utility maximization that is irrelevant of the effect on others—such engaging in sports to improve one's health, engaging in consensual sex, or recreational activities. Also, it should be noted that those scoring high on the D-factor aren't always uncooperative, as they can be very strategic in choosing when to cooperate. Their key prediction is that those scoring high on the D-factor will not be motivated to increase the utility of others (helping others in need) without benefiting themselves, and will not derive utility for themselves from the utility of others (eg, being happy for the success of others).

The researchers acknowledge that the D-factor can be manifested in a large number of ethically, morally and socially questionable attitudes and behaviors. However, they propose that any single dark trait will boil down to at least one of the defining features of the D-factor. For instance, those scoring high on narcissism might be particularly justifying of the belief that they are superior, whereas those scoring high in sadism may place a stronger emphasis on deriving utility from actively provoking disutilities for others. Nevertheless, they argue that any single dark trait will be related to at least one (and typically several) of the defining aspects of the D-factor; ie, there is a substantial common core underlying individual differences on all measures of dark traits.

Again, the g-factor analogy is apt: while there are some differences between verbal intelligence, visuospatial intelligence, and perceptual intelligence (ie, people can differ in their pattern of cognitive ability profiles), those who score high on one form of intelligence will also tend to statistically score high on other forms of intelligence.

So what did they actually find?

The Actual D-Factor

Across four studies, the researchers found support for the existence of their proposed D-factor. To capture a reasonable D-factor, they administered nine different tests measuring a particular dark trait that has been well studied in the psychological literature. These are the nine traits that comprised their D-factor:

Egoism. The excessive concern with one's own pleasure or advantage at the expense of community well-being. Machiavellianism. Manipulativeness, callous affect and strategic-calculating orientation. Moral Disengagement. A generalized cognitive orientation to the world that differentiates individuals' thinking in a way that powerfully affects unethical behavior. Narcissism. An all-consuming motive for ego reinforcement. Psychological Entitlement. A stable and pervasive sense that one deserves more and is entitled to more than others. Psychopathy. Deficits in affect, callousness, self-control and impulsivity. Sadism. Intentionally inflicting physical, sexual or psychological pain or suffering on others in order to assert power and dominance or for pleasure and enjoyment. Self-Interest. The pursuit of gains in socially valued domains, including material goods, social status, recognition, academic or occupational achievement and happiness. Spitefulness. A preference that would harm another but that would also entail harm to oneself. This harm could be social, financial, physical or an inconvenience.

Here is a summary of their main findings:

First, they found that all of the dark traits were substantially positively related to each other (what Spearman referred to as a "positive manifold")—although some traits were more strongly correlated with each other than others. The strongest correlations were found among measures of Egoism, Machiavellianism, Moral Disengagement, Psychopathy, Sadism and Spitefulness.

Second, the pattern of items that were most strongly related to the D-factor related to aspects of their theoretical model: utility maximization ("I'll say anything to get what I want"), inflicting disutility on others ("There have been times when I was willing to suffer some small harm so that I could punish someone else who deserved it"), and justifying malevolent beliefs ("I honestly feel I'm just more deserving than others").

Third, they found that those scoring high on the D-factor were more likely to keep money for themselves when given the opportunity, and were more likely to display unethical behavior (cheating to maximize one's gain).

Fourth, the D-factor was related to a number of outcomes you would expect, including positive associations with self-centeredness, dominance, impulsivity, insensitivity, power, aggression and negative associations with nurturance, internalized moral identity, perspective taking, sincerity, fairness, greed avoidance and modesty.

Fifth, they found support for Spearman's principle of the indifference of the indicator. The D-factor captured the dark core of many different dark traits without crucially relying on any one measure. In fact, they found that even after omitting 50 percent of the items at random, and repeating this process 1,000 times, still resulted in extremely high correlations among all of the D-factors (> r=.93).

What's Your Dark Core Score?

If you've made it this far, you're probably eager to see whether you score high on the D-factor. This nine-item test should be sufficient to estimate to a reasonable degree where you would score on the D-factor. The more you are in strong agreement with multiple items on this scale, the higher the likelihood you would score high on the D-factor. If you are in strong agreement with just one item on this scale, I wouldn't be so confident that you would score high on the D-factor. However, if you are in extremely strong agreement on many of these items, there's a high likelihood that you would indeed score high on the D-factor (ie, you're a humongous asshole, objectively measured):

The Dark Core Scale

1. It is hard to get ahead without cutting corners here and there.

2. I like to use clever manipulation to get my way.

3. People who get mistreated have usually done something to bring it on themselves.

4. I know that I am special because everyone keeps telling me so.

5. I honestly feel I'm just more deserving than others.

6. I'll say anything to get what I want.

7. Hurting people would be exciting.

8. I try to make sure others know about my successes.

9. It is sometimes worth a little suffering on my part to see others receive the punishment they deserve.

© 2018 Scott Barry Kaufman, All Rights Reserved

Note: The Dark Core Scale was adapted from the larger test battery. I selected the items on an ad-hoc basis for entertainment purposes, but I do not recommend using the scale to make any sort of diagnosis. For more on the D-factor, go to www.darkfactor.org. To take the self-assessment created by the researchers of the dark factor study, go to: http://qst.darkfactor.org.