magazine issue 4 2014 / Issue 20

Judging a book by its cover: Prior knowledge determines the effect of embodied cues.

• written by Jesse Chandler
• edited by Norbert Schwarz

Research has shown that physical experiences can influence metaphorically related judgments. For example, the experience of physical weight influences estimates of value and importance. Careful examination of existing evidence suggests that how much knowledge people have about a target of a judgment determines whether the experience of physical weight influences that judgment. Three studies directly test this hypothesis, finding that participants evaluated a book as more important when it was heavy (due to a concealed weight), but only when they had substantive knowledge about the book.

In idiomatic English, people with serious problems “carry the weight of the world” on their shoulders and when faced with tough choices they may “weigh” the merits of alternative courses of action. These phrases reflect how significance or value is expressed through metaphors that suggest heft or physical substance. The association between weight and importance is old. The Latin verb pondus (to weigh or consider) lives on in the words ponderous and pensive that reflect the alternative meanings of physical and psychic weight. Likewise the Latin word gravis (heavy or serious) is survived by gravid, gravity, gravitas, and grave, all of which connote varying degrees of weight and importance.

Metaphorical associations like that between “importance” and “weight” are more than just poetic language, instead reflecting something deeper about how people think about the world. The concepts of weight and importance are tightly coupled to each other, so that when one comes to mind, the other is likely to follow. Just as the experience of physical weight (i.e. lifting a heavy book) brings thoughts related to physical weight to mind (“this feels heavy”), it also brings thoughts to mind suggestive of metaphorical weight (“this book is important’). Researchers have demonstrated this link through studies in which people who experience physical weight are faster to recognize importance related words, suggesting that related thoughts are already on their mind (Zhang & Li, 2012, for an early demonstration using a different metaphor see Meier & Robinson, 2004).

Once a physical experience brings thoughts to mind, these thoughts can in turn influence judgments that are related to it (Lee & Schwarz, 2012). Indeed, there are many demonstrations of physical weight influencing perceived importance, even when the source of weight is irrelevant to the judgment at hand. In one study researchers found that people estimated currencies as more valuable when the clipboard on which they wrote the estimate was made heavier through a concealed weight (Jostmann, Lakens & Schubert, 2009), while others have found that food seems more expensive when it is sampled from a heavier dish (Piqueras-Fiszman, Harrar, Alcaide & Spence, 2011) or when using heavier cutlery (Spence, Harrar & Piqueras-Fiszman, 2012).

Other studies have shown that the relationship between weight and importance extends beyond questions of monetary value, influencing estimates of more abstract forms of importance. Incidental experiences of physical weight lead people to ascribe more importance to abstract ideas, like fairness (Jostmann et al., 2009), and candor (Zhang & Li, 2012). People also perceive diseases as more severe (Kaspar, 2013) and allocate more money to fund  policy decisions when providing their answers on weighted, as opposed to unweighted, clipboards (Ackerman, Nocera & Bargh, 2010).

Does knowing more influence the effect of weight on judgment?

Our gut reaction to the world around us is beyond our immediate control: when we experience something any number of thoughts or feelings may come to mind. However, whether we incorporate those feelings into judgments is at least partially under our control, and thoughts and feelings must be reconciled when forming an opinion. (for a discussion see Gawronski & Bodenhausen, 2006). Given all of the additional steps involved in turning a passing thought into a well-formed opinion, it seems plausible that how physical cues are incorporated into explicit judgments about the world should be highly context sensitive, occurring sometimes, but not always. So when do physical cues, like an object’s weight, influence people’s beliefs about the world?

How much somebody knows about something may influence whether the experience of physical weight will influence their opinion of it. Intuitively, if people know more about something, they must surely rely less on irrelevant cues like weight, either because they have already formed a firm opinion, or because they have other more relevant information to draw upon. This intuition is compatible with research that shows that when people do not have a readily available answer to a problem, they may rely on a heuristic to provide a solution (Kahneman, 2011; Meier, Landau & Keefer, 2010).