Emphasizing Deckard's struggle to find his own identity, and so provoke the audience to feel as he does in their struggle to grasp Deckard's identity, and ultimately to question their understanding of how we can know our humanity is different, and how we can know at all (cf. epistemology). If the audience ignores the answer until the end, and the characters do not know it either, then the story again provokes the audience, and the characters, to ask: What is the difference between being human and being non-human, if I can be either, and I need someone else to tell me which I am?