Washing Hands Removes Doubt, Not Just Dirt
Hand Washing Can Rinse Away Doubts, Help You Live With Your Decisions, Study Finds
May 6, 2010 -- Washing your hands does more than rinse away the guilt of
sins or past misdeeds, it removes doubts about choices that have nothing to do
with morality, such as choosing celery over carrots at the grocery store, a new
Researchers at the University of Michigan say the act of hand washing helps
people live with the decisions they make, alleviating cognitive dissonance, the
uncomfortable feeling that comes from holding two opposing ideas in your mind
at the same time.
The study is published in the May 7 issue of the journal Science.
“We know that washing your hands removes the need to feel that you made the
right decision,” study author Spike W.S. Lee, a doctoral student in psychology at the University of Michigan, tells
WebMD. “People always wonder if they make right decisions. What washing does is
wash away the compulsion to justify the choice.”
The study, done with colleague Norbert Schwarz, PhD, expands on past
research indicating that hand washing is associated psychologically by many
people with guilt removal for perceived misdeeds, Lee tells WebMD.
Washing Away Doubt
The two scientists asked 40 undergraduate students to look through 30 CD
covers as part of an alleged consumer survey. The participants picked 10 CDs
they would like to own, ranking the music by preference.
Later they were offered a choice between their fifth- and sixth-ranked CDs
as a token of appreciation. After they made a choice, the participants
completed an ostensibly unrelated product survey, of liquid soap. Half looked
at the bottle before answering, and the others actually tested the soap by
washing their hands.
Still later the participants were asked to rank the 10 CDs again.
“People who merely examined the soap bottle dealt with their doubts about
their decision by changing how they saw the CDs,” Schwarz says in a news
release. “As in hundreds of earlier studies, once they had made a choice, they
saw the chosen CD as much more attractive than before and the rejected CD as
much less attractive.”
Hand-washing “eliminated this classic effect,” Schwarz says. “Once
participants had washed their hands, they no longer needed to justify their
choice when they ranked the CDs the second time around.”
Lee says in the news release that washing “reduces the influence of past
behaviors and decisions that have no moral implications whatsoever.”
Hand Washing Mimics Washing Away Sin
The study results were replicated by getting participants to choose one of
two fruit jams, and then cleanse their hands with antiseptic wipes in an
ostensibly unrelated survey.
Again, participants “who merely examined an antiseptic wipe after choosing a
jar of fruit jam expected the taste of the chosen jam to far exceed the taste
of the rejected one,” Lee says in the news release. “This difference was
eliminated when participants tested the antiseptic wipe by cleaning their