Consider the technique of positive visualization, a staple not only of Robbins-style seminars but also of corporate team-building retreats and business best sellers. According to research by the psychologist Gabriele Oettingen and her colleagues, visualizing a successful outcome, under certain conditions, can make people less likely to achieve it. She rendered her experimental participants dehydrated, then asked some of them to picture a refreshing glass of water. The water-visualizers experienced a marked decline in energy levels, compared with those participants who engaged in negative or neutral fantasies. Imagining their goal seemed to deprive the water-visualizers of their get-up-and-go, as if they’d already achieved their objective.

Or take affirmations, those cheery slogans intended to lift the user’s mood by repeating them: “I am a lovable person!” “My life is filled with joy!” Psychologists at the University of Waterloo concluded that such statements make people with low self-esteem feel worse — not least because telling yourself you’re lovable is liable to provoke the grouchy internal counterargument that, really, you’re not.