There is often a plan behind a person's apparently inexplicable behavior. Based on a line from Shakespeare's Hamlet.
Browse entries near There's method in his madness
there but for the grace of God go I
There is no joy in Mudville
There was a little girl / Who had a little curl
there's
There's many a slip 'twixt the cup and the lip
There's more than one way to skin a cat
There's no accounting for taste
there's no accounting for tastes
There's no fool like an old fool
there's no fool like an old fool (idioms)