He who lives with his senses well controlled, moderate in his food and drink, he will not be overthrown, any more than the wind throws down a rocky mountain.
It isn't that they can't see the solution. It's that they can't see the problem. They can't see the problem if they are looking in the wrong place. They can't see the problem if they have blinders on - for 'none are so blind as those that will not see'.