Emotional manipulation takes many forms, and it's often so covert that clients have difficulty articulating how and when it's happening,
Paulhus's work on the dark side of personality stems from that same scientific module in his mind. In the recent article on the dark side of personality, he notes that he got into this area because of his concern about “construct creep.”
He became worried about how researchers who studied narcissism, for example, without simultaneously thinking about Machiavellianism or psychopathy, would start to expand the term to encompass the other related, but distinct, concepts.