A term used by Geoffrey Dean and Ivan Kelly (2003) to describe affective, perceptual, and cognitive biases or illusions that lead to erroneous beliefs.
"Technically these hidden persuaders can be described as ‘statistical artifacts and inferential biases’." Dean and Kelly argued that hidden persuaders explain why many astrologers continue to believe in the validity of astrology despite overwhelming evidence that astrology is bunk. Psychologist Terence Hines, who has explored many varieties of hidden persuaders, blames them for the continued use by psychologists of such instruments as the Rorschach test, despite overwhelming evidence that the test is invalid and useless: Psychologists continue to believe in the Rorschach for the same reasons that Tarot card readers believe in Tarot cards, that palm readers believe in palm reading, and that astrologers believe in astrology: the well-known cognitive illusions that foster false belief.
Hidden persuaders sometimes seem to affect people in proportion to their intelligence: the smarter one is the easier it is to develop false beliefs.
There are several reasons for this:
(1) the hidden persuaders affect everybody to some degree;
(2) the smarter one is the easier it is to see patterns, fit data to a hypothesis, and draw inferences;
(3) the smarter one is the easier it is to rationalize, i.e., explain away strong evidence contrary to one's belief; and
(4) smart people are often arrogant and incorrectly think that they cannot be deceived by others, the data, or themselves.
Hidden Persuaders (1957) is also the title of a book by Vance Packard. He chronicled the many methods, some pretty open and obvious, that advertisers use in their quest to manipulate the thoughts and actions of consumers. Packard attempted to expose corporate propaganda as a kind of mind control operation, especially in its use of subliminal messaging.