This is a book of hypotheses - the hypotheses upon which the X-Files is constructed.
There was a time, until perhaps the beginning of this century, when the investigation of the paranormal commanded a certain respect and was conducted by professional scientists as much as by enthusiastic amateurs. Such open-mindedness ended for two reasons. Firstly, many paranormal phenomena seemed so elusive that busy physicists, chemists and biologists tired of trying to pin them down. Secondly, science became so overwhelmingly successful that, to many, the supernatural became almost superfluous. Nuclear physics, brain surgery and the advancement of space travel can be as exciting as hunting ghosts or trying to prove the existence of alien civilisations, and at the same time they are tangible with commercial and academic application.