What is the meaning of [None so blind as those who won’t see]

It is no use trying to get a person to see what he does not wish to see, or to
understand what he chooses not to understand, or to attract his attention when
he has decided to ignore you.

> ‘I’ve been trying to catch his eye ever since he came into the hall, but
he’s always looking some other way.’

> ‘There’s none so blind as those who won’t see.’

##### See also:

* A nod is as good as a wink to a blind horse