In "Just Lather, That's All", what idea do you suppose the author was developing through the story?

This is a fascinating question, because at first glance it
is hard to work out what the meaning is in this excellent tale of suspense. However, for
me, the meaning of the story comes at the end of the tale, when the internal conflict of
the barber is resolved as he decides not to kill Captain Torres and he seems to
recognise both his place in the world, and also the place of Captain
Torres:

But I
don't want to be a murderer. You came to me for a shave. And I perform my work
honourably... I don't want blood on my hands. Just lather, than's all. You are an
executioner and I am only a barber. Each person has his own place in the scheme of
things.

It is this
recognition of every person having their own place "in the scheme of things" that
suggests that the barber comes to have a grudging respect for Captain Torres, because he
recognises that every person has a specific role in life that they are made for, and
that they are made to do to the best of their ability.

What
is key to this theme is the final paragraph, where we, along with the barber, are
shocked to discover that Captain Torres new all along that the barber was a
rebel:

In the
doorway he paused for a moment and said, "They told me that you'd kill me. I came to
find out. But killing isn't easy. You can take my word for it." And he turned and walked
out.

What is interesting is
that this final paragraph suggests that Captain Torres has also gained grudging respect
for the barber. We know that Captain Torres is an executioner, and thus it is surprising
that he lets the barber live and walks out. Perhaps he too has come to have a grudging
admiration for the barber and his recognition of his place in "the scheme of things." It
also suggests another side to the supposedly brutal Captain Torres, a side that shows it
is not easy to kill, maim and torture.