Two possibilities exist: Either we are alone in the Universe or we are not. Both are equally terrifying.
Arthur C. ClarkeThough the man-apes often fought and wrestled one another, their disputes very seldom resulted in serious injuries. Having no claws or fighting canine teeth, and being well protected by hair, they could not inflict much harm on one another. In any event, they had little surplus energy for such unproductive behavior; snarling and threatening was a much more efficient way of asserting their points of view.
Arthur C. ClarkePerhaps, as some wit remarked, the best proof that there is Intelligent Life in Outer Space is the fact it hasn't come here. Well, it can't hide forever - one day we will overhear it.
Arthur C. Clarke