Ancient Greeks wore masks to express the emotions of the characters they were playing during dramatic productions. There was a pragmatic reason for this–it was often difficult for those seated far away to see what emotion the character being portrayed was feeling. And so the exaggerated face could be seen from the furthest reaches of the mezzanine. But adopting the persona of a subject has been employed long before Antiquity. At the onset of our own social and neurological development, we act. We pretend. We are someone else. It is, thus, natural for writers to attempt to embody the voices, thoughts, and actions of the other.