21(10) 1423 –1425
© The Author(s) 2010
Reprints and permission:
Water and soap remove more than physical dirt―they attenuate
guilt from one’s moral transgressions (Zhong & Liljenquist,
2006) and soften one’s judgment of others’ misdeeds (Schnall,
Benton, & Harvey, 2008). Conversely, immoral acts increase the
appeal of physical cleansing (Zhong & Liljenquist, 2006). Such
findings indicate that abstract thought about morality is grounded
in concrete experiences of physical cleanliness (Lakoff &
Johnson, 1999). Natural language use associates this moral-
purity metaphor with specific body parts (e.g., “dirty hands,”
“dirty mouth”), suggesting that the motor modality involved in a
transgression may figure prominently in the embodiment of
moral purity. If so, people should prefer purification of the
“dirty” body part over purification of other body parts.
We tested this conjecture, which is compatible with the
canon of embodiment (Barsalou, 2008; Niedenthal, Barsalou,
Winkielman, Krauth-Gruber, & Ric, 2005), by inducing par-
ticipants to perform the same immoral act (conveying a malev-
olent lie) or moral act (conveying a benevolent message) with
their mouths (by using voice mail) or their hands (by using
e-mail). Their subsequent desire for mouthwash and for hand
sanitizer served as the dependent variables. If the embodiment
of moral purity is independent of motor modality, as previous
research implicitly assumed, both cleaning products should be
more attractive to people after they convey a malevolent mes-
sage than after they convey a benevolent message; if the
embodiment is sensitive to motor modality, however, mouth-
wash should be particularly desirable after lying in a voice
mail, and hand sanitizer should be particularly desirable after
lying in an e-mail. Note, however, that people not only avoid
physical contact with morally tainted people and objects,
but also seek physical contact with virtuous ones (Rozin &
Nemeroff, 1990). Hence, they may not only attempt to remove
the metaphorical residue of immoral acts, but also avoid remov-
ing the residue of virtuous acts. In this case, people would find
mouthwash particularly unappealing after conveying a virtu-
ous message in a voice mail and hand sanitizer particularly
unappealing after conveying a virtuous message in an e-mail.
Eighty-seven undergraduates (34 male, 53 female) participated
in our experiment for course credit and were randomly assigned
to conditions in a 2 (modality: mouth vs. hands) × 2 (ethicality:
unethical vs. ethical) between-subjects design. Told that they
were taking part in a personality study, participants enacted a
scenario modeled after one used by Zhong and Liljenquist
(2006). Each person imagined being a law-firm associate com-
peting for promotion with a colleague, Chris, and finding an
important document that Chris had lost. Returning the docu-
ment would help Chris’s career and hurt the participant’s own
career. The participant was instructed to leave Chris a voice
mail (mouth) or type Chris an e-mail (hands) telling him “who
you are” and explaining that “you could not find his document”
(unethical) or that “you found his document” (ethical). The par-
ticipant actually delivered the message, allegedly to provide
verbal material for personality analysis.
Next, participants rated the desirability of several products
(1 = completely undesirable, 7 = completely desirable) as part
of an ostensible marketing survey and reported how much they
were willing to pay (WTP) for each one (“$__”). The products
included mouthwash and hand sanitizer. The participants were
then given a funnel debriefing. None of them indicated any
suspicion about the experiment’s true purpose.
Desirability and log-transformed WTP data were standardized
and submitted to a 2 (ethicality: ethical, unethical) × 2 (modal-
ity: hands, mouth) × 2 (product: hand sanitizer, mouthwash) ×
2 (measure: desirability, WTP) mixed analysis of variance
Spike W.S. Lee, Department of Psychology, University of Michigan,
530 Church St., Ann Arbor, MI 48109-1043
Dirty Hands and Dirty Mouths:
Embodiment of the Moral-Purity Metaphor
Is Specific to the Motor Modality Involved
in Moral Transgression
Spike W.S. Lee and Norbert Schwarz
University of Michigan
Received 3/9/10; Revision accepted 4/18/10
1424 Lee, Schwarz
(ANOVA), with the last two factors being within subjects. An
Ethicality × Modality × Product interaction, F(1, 81) = 10.29,
p = .002, indicated a significant role of motor modality, which
was not moderated by measure (F < 1 for the four-way inter-
action). The two measures were averaged, with higher scores
indicating higher desirability and WTP.
As shown in Figure 1a, participants evaluated mouthwash
more positively after lying in a voice mail (M = 0.21, SD =
0.72) than after lying in an e-mail (M = –0.26, SD = 0.94),
F(1, 81) = 2.93, p = .03 (one-tailed), d = 0.55 (simple main
effect), but evaluated hand sanitizer more positively after lying
in an e-mail (M = 0.31, SD = 0.76) than after lying in a voice
mail (M = –0.12, SD = 0.86), F(1, 81) = 3.25, p = .04 (one-
tailed), d = 0.53 (simple main effect). The Modality × Product
simple interaction was significant under unethical conditions,
F(1, 81) = 7.45, p = .008.
In contrast, participants evaluated hand sanitizer less posi-
tively after telling the truth in an e-mail (M = –0.33, SD =
0.82) than after telling the truth in a voice mail (M = 0.23,
SD = 0.70), F(1, 81) = 5.02, p = .03, d = 0.74 (simple main
effect). However, modality did not affect their evaluation of
mouthwash, F < 1 (Fig. 1b). The Modality × Product simple
interaction was marginally significant under ethical condi-
tions, F(1, 81) = 3.29, p = .07.
These findings indicate that the embodiment of moral purity is
specific to the motor modality involved in a moral transgres-
sion, making purification of the “dirty” body part more desir-
able than purification of other body parts. Consistent with this
observation, reanalysis of earlier findings shows that copying
Voice Mail: Mouth E-mail: Hands
Voice Mail: Mouth E-mail: Hands
Fig. 1. Participants’ mean evaluation of mouthwash and hand sanitizer as a function of the motor modality (mouth
or hands) of (a) unethical acts and (b) ethical acts. Error bars represent standard errors of the mean.
Embodiment of the Moral-Purity Metaphor 1425
(rather than enacting) a story about immoral others increases
the desire to clean the external world (as reflected in evalua-
tions of detergent and disinfectant, ds = 1.15 and 0.75) more
than the desire to clean one’s own body (as reflected in evalu-
ations of soap, d = 0.37; Zhong & Liljenquist, 2006, Study 2).
Moreover, hand washing influences judgments of others’
transgressions more when the transgressions involve solely
the hands (ds = 0.61–0.81) rather than additional body parts
(ds = 0.28–0.45; Schnall et al., 2008). In addition, our findings
indicate that the embodiment of moral purity extends to virtu-
ous acts: Having typed a virtuous e-mail made hand sanitizer
unappealing, a result suggesting that people may avoid rinsing
away residues of virtue (Bloom, 2009; Rozin & Nemeroff,
1990); however, parallel effects were not observed for mouth-
wash. In natural parlance, metaphorical references to “clean
hands” seem more common and natural than metaphorical ref-
erences to a “clean mouth,” raising the possibility that acces-
sibility of an applicable metaphor is a crucial ingredient for the
observed effects (Chandler & Schwarz, 2009).
Going beyond moral purity, numerous studies have demon-
strated the pervasive effects of embodied metaphors in the
social domain (for reviews, see Landau, Meier, & Keefer, in
press; Williams, Huang, & Bargh, 2009). The present findings
suggest that such effects should be more pronounced when the
motor modality of the metaphor-priming task matches the
motor modality of the downstream judgment and behavior.
Declaration of Conflicting Interests
The authors declared that they had no conflicts of interest with
respect to their authorship or the publication of this article.
The first author was supported by an R.C. Lee Centenary Scholarship.
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