The law in a certain village requires that any wife who can prove that her husband has been unfaithful must shoot him before sundown on the same day. Every wife reasons perfectly, and all the wives know this. Further, every wife knows instantly when another’s husband has been unfaithful but never whether her own is.
One day the mayor announces that there is at least one unfaithful husband in the village. In fact there are 40 unfaithful husbands, but the wives do not know this. What happens?