'Do you believe that the sky is blue? That the grass is green?' asked the blind man of the monk.
'Certainly I do,' replied the monk.
'And how do you know this to be true?' returned the blind man.
'For verily I can see it with mine own eyes.' came the reply.
'Then prove to me that the sky is blue. Prove to me that the grass is green.' said the blind man.
'Alas, I cannot,' lamented the monk.
'Worry not,' said the blind man, 'For truly do I know that the grass is green. However, I put it to you that the sky is not blue, but merely it is a trick of the light. See now that appearance is not necessarily reality, and always subjective; and proof, however compelling, is never certain. How then, do you expect to prove your beliefs to me, if you cannot prove even that the grass is green? The answer of course, is that you should not. For one thing, proof denies faith. We are all of us blind in our own way, yet none of us completely. Just because a man has a belief that does not coincide with your own, do not assume him a fool, lest he assume the same of you.'