Definition
The dark factor, often written as the D-factor, is the idea that the various dark personality traits — narcissism, Machiavellianism, psychopathy, sadism, spitefulness, and others — are not independent characteristics but surface expressions of a single deeper tendency.
That underlying tendency is defined as placing one's own goals above those of others, even at a cost to others, together with beliefs that justify doing so. A person high in D will tend to score high on several dark traits at once, because they all draw from the same well.
Why it matters
How it works
Researchers model the D-factor much like general intelligence is modeled: a broad latent trait sits beneath narrower, observable ones. Someone high in D consistently prioritizes personal benefit, discounts the welfare of others, and holds rationalizations — the world is competitive, others would do the same — that license exploitation.
Crucially, the justifying beliefs do real work. They reduce guilt, sustain a positive self-image, and make harmful behavior feel acceptable to the actor. This is why people high in the dark factor can act manipulatively while sincerely believing they are reasonable or even fair.