There is an allegory that I would like to share that I think can useful for teachers who want to give their students a more postmodern awareness about the concept of normality.  This is my version, not exactly the way it was originally written and I always offer my 'apologies' to the author (whose name I have long ago forgotten, but the idea of the story always remained)... called "The Valley of the Blind". 

The story is of a young airman who crashes his plane into a very remote valley and is knocked unconscious and injured badly. He is rescued by the people who live in that  part of the valley and taken to their village where they care for him.  He he gradually gets better, but during his recovery he discovers that his recuers are blind and have no eyes. 

The airman's injuries take time to heal but his helpers are caring and continue trying to assist him in everyway they can.  Over time, the airman learns their language and tries to tell his rescuers about himself, about where he comes from, and about the rest of the world.... 

But the people are much disturbed by his story and confer amongst themselves and come to a decision.  They agree to heal him they must take him to a special place where medical work is performed.  Once they are there, they tie him to table and they tell him that they have had to make a difficult decision that he is not normal, as he raves about something bizarre that he calls 'sight'.  And, so, they have concluded that this bizarre behaviour must be caused of the funny growths on the front of his face....

And so, of course, they remove his eyes, so that he might be normal.

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