Jesus says not to bother washing

Jared Diamond writes in Guns, Germs, and Steel about why Europeans infected Native Americans with deadly diseases rather than the other way around. Diamond writes about their close contact with domesticated animals, which Native Americans did not have. After thousands of generations, the remaining Europeans were tolerant of the germs and diseases that the domesticated animals carried while Native peoples were not.

Gregory Clark writes in A Farewell to Arms about the same issue and focuses his attention on the peculiar European habit of living above your fecal waste. This had the same evolutionary effect: only those who could survive this germ-fest lived to reproduce, thereby making Europeans in general more resistant to diseases that wiped out Native populations.

Both authors are afraid to look at how ideas influence behavior, and so they fail to understand why premodern Europeans had such negligent bathing habits. The answer is easy. Jesus says not to bother washing your hands before you eat since what goes into the mouth cannot defile you, only what comes out can do that. Jesus is following Plato and developing a metaphysics in which spiritual truths are divorced from physical reality.

Both Homer and Hesiod emphasize for ancient Pagans the importance of washing, especially your hands. Jews ritually wash their hands during Sabbath. Muslims ritually wash their whole bodies five times a day. Only Christians are allowed to be filthy; and, despite their howling rejection of evolutionary theory, being filthy gave Europeans the evolutionary advantage of being resistant to many dread diseases for the simple reason that those who were not naturally resistant simply died leaving only the powerfully filthy ones to conquere the world.