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It is common knowledge that we need sleep to maintain physical health. A lack of sleep can also have a negative psychological impact. A recent study of 71 Norwegian cadets supports the idea that a lack of sleep can also have negative moral consequences:
"Prior to being sleep-deprived, the cadets were asked to take the Defining Issues Test, an examination based on Lawrence Kohlberg's stages of moral development. Those who score well on the test demonstrate the ability to think abstractly about moral decisions, to effectively weigh harm vs. benefit. Those who score poorly tend to give self-serving answers or strictly follow the rules without evaluating the consequences."
When the cadets had a good night's rest--an average of 8 hours--they scored well on the test. When they had much less sleep, roughly 2-3 hours (which is common in combat situations) they scored poorly on the test. Perhaps this is at least part of the reason for some of the morally questionable and immoral choices made in combat situations. Most of us will fortunately never face such situations. What relevance might this study have for us?
A bit of introspection and consultation of common sense supports the conclusion of this study. When rested, we are more likely to have a more general sense of well-being which can support moral motivation. When tired, such motivation can be undermined. Fatigue can make us more prone to being frustrated, angry, and anxious. I am certainly less patient with my children and with my students when I'm in need of sleep.
A good night's sleep is not sufficient for having good character. However, it looks like it is one more thing we can do to promote it in ourselves. And given the fragility of goodness in many situations that we find ourselves in, every little thing we can do to strengthen our character is worth the effort.
