User blog comment:Glflegolas/Human Extinction -- are we approaching the Doomsday?/@comment-25746895-20150309160758/@comment-25330335-20150309220410

But if these supposed highly advanced species does exist, they may be so different from humans that we could never understand their logic. What I mean by this is that perhaps the species knows of us, or multiple species know of us, but keeps themselves secret according to their wisdom/intergalictic law. Think The Shadow Proclamation in DW.