to hoist with his own petarddoes it have something to do with poetic justice?
A Petard was the French name for a Catapult, Mangonel or Trebuchet which hurled rocks at a castle wall while under siege. Occasionally one of the crew would get caught in the ropes and be hoisted along with the rock. As explained by Jac, it means to become a victim of your own trap.
yes being caught out by your own stupidity an example maybe if I set a booby trap for someone else and then walked into it myself.
