Abstract: Physical cleansing has been a focal element in religious ceremonies for thousands of years. The prevalence of this practice suggests a psychological association between bodily purity and moral purity. In three studies, we explored what we call the "Macbeth effect"—that is, a threat to one's moral purity induces the need to cleanse oneself. This effect revealed itself through an increased mental accessibility of cleansing-related concepts, a greater desire for cleansing products, and a greater likelihood of taking antiseptic wipes. Furthermore, we showed that physical cleansing alleviates the upsetting consequences of unethical behavior and reduces threats to one's moral self-image. Daily hygiene routines such as washing hands, as simple and benign as they might seem, can deliver a powerful antidote to threatened morality, enabling people to truly wash away their sins.

Zhong, C. B., & Liljenquist, K., "Washing Away Your Sins: Threatened Morality and Physical Cleansing", Science, VOL 313 September 8 , 2006, 1451-1452

On the eve of the fifth anniversary of the Sept. 11 attacks, the American public's confidence in the ability of the U.S government to protect them from terrorism, or respond to disasters or emergencies, has dropped to startling new lows, according to a new study commissioned by the National Center for Disaster Preparedness at Columbia University's Mailman School of Public Health and The Children's Health Fund.

8 September 2006