Lady Macbeth Effect


Despite being Shakespeare’s shortest tragedy, Macbeth is known as one of the greatest theatrical plays ever written. A story about loyalty, guilt, innocence, and fate involving the iconic opening scene of three witches as they surround Macbeth and Banquo, chanting their prophecies.

One of the most intriguing characters in the play is Lady Macbeth, the wife of Macbeth himself. She serves such a powerful presence in the play, especially within the first two acts. Her most powerful scene—which became the turning point of the play—happens during the fifth act of the play, in which Shakespeare graced us with one of the most memorable lines in English literature: as Lady Macbeth believes she can’t wipe her victim’s imaginary blood off of her hands and cries, “Out, damned spot! Out, I say!”

That scene became precisely where the term “Lady Macbeth Effect” comes from.  It describes a psychological condition where individuals feel the need to wash their hands or body when feeling that they’ve done something wrong, believing that physical cleanliness reflects their moral purity.

In an experiment by Zhong and Liljenquist, a group of participants was asked to fill in the letters of three incomplete words: "W_ _H", "SH_ _ER", and "S_ _P". Those who had been asked to recall a bad deed were 60% more likely to answer with cleansing-related words such as “wash”, “shower”, or “soap”, as opposed to other words like “wish”, “shaker”, or “stop”. In another test, participants were given a choice of objects: a pencil or an antiseptic wipe. Three-quarters of participants who had recalled a ‘dirty’ act chose antiseptic wipes, and only about one-third of those who had recalled an ethical act did the same. 

“If cleanliness is related to moral purity, then the cleanliness of one’s environment could have an impact on moral behavior,” said Zhong. However, he also stated that he is uncertain of whether a clean environment might foster immoral behavior by serving as a kind of permanent psychological cleanser.


Zhong, C.-B., & Liljenquist, K. (2006). Washing Away Your Sins: Threatened Morality and Physical Cleansing. Science, 313(5792), 1451–1452. https://doi.org/10.1126/science.1130726

Writer: Manohara Diwasasri

Editor: Arinda Risma W.