Carl Jung wrote about UFOs as something of a collective hallucination, a mass psycho-spiritual phenomenon. Not in the sense that they are "unreal", but in that

Carl Jung wrote about UFOs as something of a collective hallucination, a mass psycho-spiritual phenomenon. Not in the sense that they are "unreal", but in that they tap into an extraordinary dimension of our collective awareness. I suggest checking out "Flying Saucers: a Modern Myth of Things Seen in the Sky."