Gordian Knot

The cutting of the Gordian Knot is an Ancient Greek legend associated with Alexander the Great in Gordium in Phrygia, regarding a complex knot that tied an oxcart. Reputedly, whoever could untie it would be destined to rule all of Asia. In 333 BC Alexander was challenged to untie the knot. Instead of untangling it laboriously as expected, he dramatically cut through it with his sword, thus exercising another form of mental genius. It is thus used as a metaphor for a seemingly intractable problem which is solved by exercising brute force.

Turn him to any cause of policy,
The Gordian Knot of it he will unloose,
Familiar as his garter

— Shakespeare, Henry V, Act 1 Scene 1. 45–47