What motivates the narrator to overcome his distinctive antipathy to the blind man in "Cathedral"?

In the story "Cathedral" the man is unhappy about having
to entertain a blind person.  He seems uncomfortable at having to figure out how to
relate to the man and does not really view the blind man as
normal. 

The two men relax in the evening and eventually a
beautiful cathedral comes into view on the television.  When the blind man asks the man
to describe it, he finds that he does not have the ability to describe such a thing of
beauty in a way that someone blind can relate to it. The blind man asks him to draw it,
but the man feels that he is inferior in art.  The blind man takes the man's hand as he
draws the cathedral. 

The act of the man drawing the
cathedral and taking the blind man on a journey of movement connects them in a very
different manner.  The man is amazed that by drawing he is sharing the experience with
the blind man which opens himself up to seeing things in a new way as
well.