The child who is locked up in "The Ones Who Walk Away from Omelas" represents a scapegoat.
The subtitle of Le Guin's story is "Variations on a Theme by William James." This subtitle indicates that William James's philosophy of pragmatism was the inspiration for Le Guin's narrative. According to this philosophy, the meaning of a proposition is found to be true if its practical application is successful.
The narrative indicates that life in Omelas is pleasant, and "the children were, in fact, happy." This happiness is pragmatic:
Happiness is based on a just discrimination of what is necessary, what is neither necessary nor destructive, and what is destructive.
In the basement of one of the buildings in Omelas, there is a "feeble-minded" child who bears the burden of misery so that all the others can live without any conditions that cause imperfection. This child, who has the role of scapegoat, has no understanding. However, "all the people of Omelas....know it has to be there" because...
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