What is it that separates human beings from the so called lower animals? Well as I see it, it's exactly one half dozen significant things: Humor, Imagination, Eroticism - as opposed to the mindless, instinctive mating of glow-worms or raccoons - Spirituality, Rebelliousness, and Aesthetics, an appreciation of beauty for its own sake. Now, since those are the features that define a human being, it follows that the extent to which someone is lacking in those qualities is the extent to which he or she is less than human. Capisce?