This is an aphorism from my aphorism book.
제 꾀에 넘는다
je kkoe·e neom·neun·da
one’s-own trap-LOC run-accross-PRES
[One] falls in one’s own trap.
This is essentially “Hoisted with one’s own petard” – an English aphorism of Shakespearean origin that was always utterly opaque to me, since petard is no longer anything but an archaic word.
A petard was a small, simple gunpowder bomb used to blow up walls and doors in the renaissance period, and the meaning of hoist in this expression is “get blown up by.” So the Shakespearean phrase simply means “Get blown up by one’s own bomb.”
[daily log (11 pm): walking, 5 km]