What is Human?

One of the main themes running throughout Blade Runner is the question that comes up repeatedly as to what makes a person a human being. Is a human being determined solely on the basis that they were born in the usual sense, as a result of the union of two other human beings? Does this mean children born as a product of artificial insemination with sperm from donors are not real human beings? The Replicants were produced by Tyrell Corporation to be "more human than human," and these simulated humans are indeed, quite capable of becoming more than the sum of their parts.

The Replicants in Blade Runner are supposed to be void of emotion. It quickly becomes obvious that they have plenty of emotion. When Rachel seeks out Deckard to ask him questions about her existence, he hesitates, but as she is telling Deckard about...