My dear old grandfather Litcock said, just before they sprung the trap, you cant cheat an honest man. Never give a sucker an even break or smarten up a chump.
ATTRIBUTION:
George Marshall, and Eddie Cline. Larsen E. Whipsnade (W.C. Fields), You Cant Cheat an Honest Man, retort to a man who accuses him of dishonesty (1939).
Fields old friend Eddie Cline was the uncredited director for all the comedians scenes.