What if there are other species or life forms out there that are orders of magnitude smarter than us and we simply aren't intelligent enough to recognize signs of them when we see 'em?
Absence of evidence is not evidence of absence.
http://lesswrong.com/lw/ih/absence_of_evidence_is_evidence_o... http://c2.com/cgi/wiki?AbsenceOfEvidenceIsNotEvidenceOfAbsen...
Which would mean us as humans would not have any way to verify this, unless we ourselves elevate ourselves to the level of these possible lifeforms and observe from there.
Like, do the fish in the deep sea believe that humans exist? Probably not, but we do exist. These fish just have no way of reaching us or perceiving us, unless we visit them with probing lights and everything.
And what would these fish think if they saw one of us, they having no point of reference, perhaps not even any way to model our presence, as they have never seen such thing ?
Ps. I've seen a bright light fly in a spiral motion, and then quickly accelerate off to the distance. Here though, I probably get downvoted by anyone who only believes what is written and not experienced.