I think Keller's purpose was to show the fundamental humanity of people with disabilities, and part of that is explaining her internal life as a child who could not see or hear. There is a kind of otherness to her mature writing which seems at odds with her stories about her childhood, as if her writing self was a kind of abled guide and almost a separate person to her disabled self.
She explains as much at the beginning of her book, when she speaks of her childhood, that
. . . when I try to classify my earliest impressions, I find that fact and fancy look alike across the years that link the past with the present. The woman paints the child's experiences in her own fantasy.
Her description of her childhood, her relationship with Martha Washington and the pranks she played on her mother and her teacher, Anne Sullivan, suggest that, for all her difference, Helen was still the precocious girl she was before the illness that took away her sight and hearing. In that sense, the story of her...
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