Unless you're mildly retarded and cant comprehend a civilisation prior to this epoch with more advanced technology. 

 I mean,  do you really think all of those UFO video's on utube are fake ?  WTF do you think has been flying around for the last 1000 Years. 

 Is it really that hard to accept that in the entire known gigantic universe , that there are other more developed beings that   were perhaps, in existence for a million, or even a billion years before Earth was formed.