Regardless of whether you’re superstitious or not, you’ve probably knocked on wood sometime in your life. But why are we ingrained to do so as a culture? Recent research suggests that while knocking on wood won’t necessarily bring a desired result, knocking on wood is effective because it primes our brains via the “avoidant action.” The New York Times has a good summary of the psychological effect behind the wood knocking:
Research finds that people, superstitious or not, tend to believe that negative outcomes are more likely after they “jinx” themselves. Boast that you’ve been driving for 20 years without an accident, and your concern about your drive home that evening rises. The superstitious may tell you that your concern is well founded because the universe is bound to punish your hubris. Psychological research has a less magical explanation: boasting about being accident-free makes the thought of getting into an accident jump to mind and, once there, that thought makes you worry.
That makes sense intuitively. What’s less intuitive is how a simple physical act, like knocking on wood, can alleviate that concern.
In one study, to be published in the Journal of Experimental Psychology: General, one of us, Jane L. Risen, and her colleagues Yan Zhang and Christine Hosey, induced college students to jinx themselves by asking half of them to say out loud that they would definitely not get into a car accident this winter. Compared with those who did not jinx themselves, these students, when asked about it later, thought it was more likely that they would get into an accident.
After the “jinx,” in the guise of clearing their minds, we invited some of these students to knock on the wooden table in front of them. Those who knocked on the table were no more likely to think that they would get into an accident than students who hadn’t jinxed themselves in the first place. They had reversed the effects of the jinx.
Knocking on wood may not be magical, but superstition proved helpful in understanding why the ritual was effective. Across cultures, superstitions intended to reverse bad luck, like throwing salt or spitting, often share a common ingredient. In one way or another, they involve an avoidant action, one that exerts force away from oneself, as if pushing something away.
While almost any behavior can be turned into a superstitious ritual, perhaps the ones that are most likely to survive are those that happen to be effective at changing how we feel. We can seek to rid ourselves of superstitions in the name of enlightenment and progress, but we are likely to find that some may be hard to shake because, although they may be superficially irrational, they may not be unreasonable. Superstitious rituals can really work — but it’s not magic, it’s psychology.