One for a Friend
Churchill, the grand master of the rejoinder, made a habit of hoisting people by their own petards. He did it with his legendary response to Bernard Shaw, who had invited him to the opening-night performance of one of his plays. Shaw sent two tickets, “one for yourself and one for a friend—if you have one.” Churchill could not attend but asked if he could have tickets for the second-night performance— “if there is one.”