It's Biblical

"There are none so blind as those who will not see" Understanding cannot be forced upon someone who chooses to be ignorant.

Matthew 13:13
: : : 13:13 Therefore I speak to them in parables: because they seeing
: : : see not; and hearing they hear not, neither do they understand

: : : Jeremiah 5:21
: : : Hear now this, O foolish people, and without understanding; which have eyes, and see not; which have ears, and hear not:

: : : Isaiah 6:9-10
: : : And he said, Go, and tell this people, Hear you indeed, but understand not; and see indeed, but perceive not.
: : : Make the heart of this people fat, and make their ears heavy, and shut their eyes; lest they see with their eyes, and hear with their ears, and understand with their heart, and convert, and be healed