Most conspiracy theory is fueled by a desire to see the universe as ultimately intelligible — the bargain being that things can make sense, but only if you believe in pervasive totalitarian malice. Alien conspiracy theory keeps the malice (cover-ups at Roswell, the Men in Black). read more
People believe in aliens for a number of reasons. First, most sci-fi movies show aliens as being found just about everywhere you might visit. Next, evolution teaches that life will develop wherever the conditions are suitable for life and it looks like there are probably a lot of suitable planets somewhere in the universe. read more