Man is the religious animal. He is the only religious animal. He is the only animal that has the True Religion — several of them. He is the only animal that loves his neighbor as himself and cuts his throat, if his theology isn’t straight. He has made a graveyard of the globe in trying his honest best to smooth his brother’s path to happiness and heaven.

Mark Twain (1835-1910) American writer [pseud. of Samuel Clemens]

Letters from Earth (1939)