The one thing that all DARK personality traits have in common- the ‘D-factor’

As per research from the University of Copenhagen, ‘Dark Triad’ personality traits include sadism, psychopathy, narcissism, or Machiavellianism, while others, also descriptive of a dark core, consist of egoism, spitefulness, and entitlement.
However, is there a unifying ‘factor’ among those dark traits?
Researchers recognize that the so-called D-factor has the potential to be present in a number of morally bankrupt attitudes and behaviors. Furthermore, it is proposed that any ‘dark trait’ will boil down to at least one of the features of the aforementioned ‘factor’.
For instance, a person who has a strong presence of sadistic qualities could have the inclination of putting quite a big emphasis on“maximiz[ing] one’s individual utility — disregarding, accepting, or malevolently provoking disutility for others — accompanied by beliefs that serve as justifications,” or also called, as already mentioned, the D-factor.
Having said that, however, they also argue that any ‘dark trait’ is correlated with at least one (even several) of the defining aspects of the D-factor.
Therefore, there is a considerable ‘common core’ relating individual differences on all measured dark traits.
Furthermore, in a recent paper called “ The Dark Core of Personality,” published in the Psychological Review, 2,500 people were questioned and asked to agree or disagree with statements of the following nature: “It is hard to get ahead without cutting corners here and there,” “It is sometimes worth a little suffering on my part to see others receive the punishment they deserve,” or “I know that I am special because everyone keeps telling me so.”
Participants were also asked about their aggression, impulsivity, and selfish or unethical behavior.
This experiment, in turn, validates the aforementioned hypothesis that a common denominator among dark aspects of personality exists.
Similarly to the notion that scoring high on an intelligence test signifies that the person will score high in other tests, the research suggests dark traits are all an expression of the same mental outlook on life, named the D-factor.
Hence, here are the nine most common dark personality traits identified by the aforementioned research:
1. Egoism
The unrestrained, excessive need to put one’s own needs and desires first, disregarding the those of others- be it, close family and friend, work colleagues or acquaintances.
2. Machiavellianism
The belief that the end ultimately makes the means justifiable, again disregarding the harsh consequences such thought process and actions might bring.
3. Moral disengagement
The ability to conduct oneself in an unethical, even morally bankrupt manner without experiencing fear of the consequences.
4. Narcissism
The attention-seeking self-obsession with oneself, in combination with a painted grandiose self-image which marks most everyone as inferior to said persona.
5. Psychological entitlement
The belief that a person is superior, thus much better than everyone and is deserving of better treatment in comparison to others.
6. Psychopathy
The complete lack of empathy or remorse, combined with reckless, antisocial behavior and the inability to form meaningful personal relationships.
7. Sadism
The desire to impose physical or emotional harm on other people due to the enjoyment that it brings along with itself.
8. Self-interest
Quite simply put, the endless craving of social and especially financial success (above anything else).
9. Spitefulness
Possessing a destructive nature, whilst being willing to cause harm to others even if that includes the person ending up hurt themselves as well.