Assuming that UFOs represent extraterrestrial visitors (whether humanoid aliens in spacecraft or something stranger), there's no denying the secretive way in which the phenomenon has unfolded since the dawn of the "modern" UFO era in 1947. Strident debunkers have seized on the "ufonauts'" seeming desire to remain unseen as evidence that they don't exist -- and maintain that studying evidence that might suggest the contrary can only be a waste of resources. Although I think the debunking argument is steeped in anthropocentric baggage, it's a fair enough question, at least in principle: Why would aliens go to the trouble of crossing interstellar distances if they possessed no interest in revealing themselves?
There are several possible answers, none of them particularly comforting.
1.) We're being observed as part of some long-term anthropological study. In this scenario, occasional run-ins with UFOs and their occupants are purely accidental. The aliens rely on a screen of plausible deniability, lurking where least expected in order to further their scientific aims and taking considerable effort to leave the human population unsuspecting.
2.) We're being prepared, however patiently, for contact at some later time. Maybe the aliens are engaged in a psychosocial campaign designed to inoculate us to the presence of "others," thus ensuring we make for interesting company when we're eventually deemed ready for open dialogue.
3.) On the other hand, perhaps we're being harvested like so many unsuspecting cattle. Much of the "abduction" literature is concerned with the alleged taking of reproductive material and the creation of human-alien "hybrid" offspring. Author David Jacobs, for one, sees a distinctly malevolent agenda afoot. In his book "The Threat," he describes what amounts to an impending takeover by aliens who've been stealthily acclimating themselves to our planet. In my opinion, Jacobs' perspective is severely limited; nevertheless, it provides an engagingly paranoid synthesis that deserves attention if only to be intelligently refuted.
4.) The aliens are here for purposes that have little or nothing to do with us. Earth could be a way-station or even a vacation spot. Similarly, the aliens could be avoiding open contact for much the same reason humans avoid "open contact" with chimpanzees: we have nothing of value to gain that can't be deduced from passive observation.
5.) In the same spirit as number two (above), the aliens might desire contact but consider our social paradigms too fragile to accommodate a meaningful exchange of ideas. If our own history is any indication, abrupt encounters between cultures of differing technological prowess end in disaster; the aliens could be entirely aware of such a risk, deciding to monitor our social evolution until we're up for the challenge.
The problem with the above scenarios is the unwelcome (and often deliberately ignored) complexity of the UFO phenomenon. We seem to be dealing with an intelligence every bit as "paranormal" as it is "technological" -- but then again, isn't that what we might realistically expect from beings thousands or perhaps millions of years more advanced than us?
Discerning UFO researchers have noted the failure of "nuts and bolts" hypotheses to adequately address the weirdness that accompanies so many UFO-related events, calling the conventional interpretation of UFOs as spacecraft into serious question. Sizing up the phenomenon from the early 21st century, it would seem that visiting ETs could do a much better job at concealing their presence if they truly desired. Far from constituting a paradox, this begs us to reconsider the motives of a truly alien intelligence, even is that means casting away much of the ufological conventional wisdom (to say nothing of SETI dogma) in the process.
This piece originally appeared at aboutSETI.com.