Original: Why I Am Not a Christian is a 1927 essay by the British philosopher Bertrand Russell hailed by The Independent as '' devastating in its use of cold logic '' , Amazon entry and listed in the New York Public Library 's list of the most influential books of the 20th century .
Simplified: At first , a talk given March 6 , 1927 at Battersea Town Hall , at the South London Branch of the National Secular Society .