It doesn't matter what reputable IQ test you take, where you take it, or what you had for breakfast the day you sat down to get your intelligence measured. Whatever the circumstances of the exam, your score is likely to be pretty close to the same.

That, psychologists explain, is because of the G-factor--a generalized level of cognitive skill we all have that largely holds steady across our lives and across different areas of intelligence (verbal, quantitative, or spatial, say). New research has found the same thing is true of evilness.

Like IQ, but for evilness

In a fascinating new Scientific American article, psychologist and author Scott Barry Kaufman explains the recent discovery of the D-factor--or darkness factor. Humans might each have their own flavor of evilness--some are narcissists obsessed with their own specialness, some are psychopaths who fail to feel others' pain, other creeps are sadists who downright enjoy it--but all these traits have a common core, a research team from Germany and Denmark found.

Underlying all these "dark" traits is "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," according to the researchers. Or, in brief, all evilness stems from a willingness to sacrifice other people's well-being for your own satisfaction.

The researchers further broke down evilness into nine component parts, from Machiavellianism to entitlement to spitefulness, which you can read all about in Kaufman's in-depth article. But the bottom line idea is that evilness, like IQ, is a single trait that can be consistently measured.

How evil are you?

Helpfully, Kaufman provides a nine-point quiz to give you a sense of your own D-factor. (Or, if you suspect people in your life of having a seriously dark core, you can try to imagine how they'd answer each question--it's not scientific in the slightest, but it is satisfying.)

"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," explains Kaufman. Here's the quiz:

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.

How did you do?