'Now when the man with the discharge becomes cleansed from his discharge, then he shall count off for himself seven days for his cleansing; he shall then wash his clothes and bathe his body in running water and will become clean.' (Lev. 15:13)

Interestingly, the practice of handwashing was re-introduced to medicine in 1846 by a brave medical resident in Austria, Ignaz Semmelweis. He did an experiment in the childcare clinic where he worked, asking doctors to wash their hands between assisting patients. Patient deaths immediately fell by 90 percent.

In spite of this, Semmelweis was ridiculed by the doctors, fired from his hospital, made professionally unemployable, and was eventually driven out of Vienna entirely. He died broke in Hungary, in a psychiatric hospital, after suffering a severe beating by asylum guards.

• I have learned that institutions more often resist truth than welcome it.
• This illustrates the observation usually attributed to George Orwell, that "In a time of universal deceit — telling the truth is a revolutionary act."
• Register for this month’s free worldwide video event: “How Do YOU Know?”