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The Power of Suggestion — What We Expect Influences Our Behavior

What can explain the powerful and pervasive effect that suggestion has in our lives?

The answer lies in our ‘response expectancies,’ or the ways in which we anticipate our responses in various situations. These expectancies set us up for automatic responses that actively influence how we get to the outcome we expect. Once we anticipate a specific outcome will occur, our subsequent thoughts and behaviors will actually help to bring that outcome to fruition.

So, if a normally shy person expects that a glass of wine or two will help him loosen up at a cocktail party, he will probably feel less inhibited, approach more people, and get involved in more conversations over the course of the party. Even though he may give credit to the wine, it is clear that his expectations of how the wine would make him feel played a major role.

But it’s not just deliberate suggestion that influences our thoughts and behaviors — suggestions that are not deliberate can have the very same effects. As the authors point out, “simply observing people or otherwise making them feel special can be suggestive,” a phenomenon termed the Hawthorne effect. As a result, people might work harder, or stick to a task for longer. And this case is more worrying, says Garry, “because although we might then give credit to some new drug or treatment, we don’t realize that we are the ones who are actually wielding the influence.”

Oh and:

“Recent research suggests that some of psychological science’s most intriguing findings may be driven, at least in part, by suggestion and expectancies,” Garry observes. “For example, a scientist who knows what the hypothesis of an experiment is might unwittingly lead subjects to produce the hypothesized effect — for reasons that have nothing to do with the experiment itself.”