Proving Our Ignorance

Physical evidence

Usually the first objection to the ETH is the lack of direct physical evidence of alien presence. Some ET believers contest this, claiming that the U.S. government is hiding wreckage from a 1947 crash at Roswell, New Mexico, but such claims are based on conspiracy theories that we shall set aside here. Not because they are necessarily wrong (although they cannot be falsified in the present context of UFO secrecy), but because like UFO skepticism they are anthropocentric, only now We know that UFOs are ETs but “They” (the government) aren’t telling. Such an assumption leads critique toward issues of official secrecy and away from the absence of systematic study, which is the real puzzle. In our view secrecy is a symptom of the UFO taboo, not its heart.

While there is no direct physical evidence for the ETH, however, there is considerable indirect physical evidence for it, in the form of UFO anomalies that lack apparent conventional explanations—and for which ETs are therefore one possibility s4IllobrandvonLudwiger,BestUFOCases—Europe(LasVegas,NV:NationalInstitute for Discovery Science, 1998); and Peter Sturrock, The UFO Enigma (New York: Warner Books, 1999).. These anomalies take four forms: ground traces, electro-magnetic interference with aircraft and motor vehicles, photographs and videos, and radar sightings like the Belgian F-16 case. Such anomalies cannot be dismissed simply because they are only indirect evidence for ETs, since science relies heavily on such evidence, as in the recent discovery of over 300 extra-solar planets (and counting) s5Peter Kosso, “Detecting Extrasolar Planets,” Studies in History and Philosophy of Science 37 (2006): 224-36.. For if UFO anomalies are not potentially ETs, what else are they?

Testimonial evidence

Most UFO reports consist primarily of eyewitness testimony. Although all observation is in a sense testimonial, by itself testimony cannot ground a scientific claim unless it can be replicated independently, which UFO testimony cannot. Such testimony is problematic in other respects as well. It reports seemingly impossible things, much is of poor quality, witnesses may have incentives to lie, honest observers may lack knowledge, and even experts can make mistakes. In view of these problems skeptics dismiss UFO testimony as meaningless.

Problems notwithstanding, this conclusion is unwarranted. First, testimony should not be dismissed lightly, since none of us can verify for ourselves even a fraction of the knowledge we take for granted s6Peter Lipton, “The Epistemology of Testimony,” Studies in History and Philosophy of Science 29 (1998): 1-31.. In both law and social science, testimony has considerable epistemic weight in determining the facts. While sometimes wrong, given its importance in society, testimony is rejected only if there are strong reasons to do so. Second, there is a very large volume of UFO testimony, with some events witnessed by literally thousands of people. Third, some of these people were “expert witnesses”—civilian and military pilots, air traffic controllers, astronauts, astronomers, and other scientists. Finally, some of this testimony is corroborated by physical evidence, as in “radar/visual” cases.

In short, the empirical evidence alone does not warrant rejecting the ETH. It does not warrant acceptance either, but this sets the bar too high. The question today is not “Are UFOs ETs?” but “Is there enough evidence they might be to warrant systematic study?” By demanding proof of ETs first, skeptics foreclose the question altogether.

“We are alone.”

Philosophers have long debated whether life exists beyond Earth s7Michael Crowe, The Extraterrestrial Life Debate, 1750-1900 (Cambridge, UK: Cambridge University Press, 1988)., but the debate has lately intensified in response to empirical discoveries like extra-solar planets, water on Mars, and “extremophile” organisms back home. A thriving discipline of astrobiology has emerged, and the view that life exists elsewhere seems poised to become scientific orthodoxy. However, this does not mean that (what humans consider) intelligent life exists. The only evidence of that, human beings, proves merely that intelligence like ours is possible, not probable. The Darwinian “Rare Earth hypothesis” holds that because evolution is a contingent process, human intelligence is a random accident, and the chances of finding it elsewhere are therefore essentially zero s8Peter Ward and David Brownlee, Rare Earth (New York: Copernicus Books, 2000)..

This is a serious argument, but there is a serious argument on the other side too, going on within evolutionary theory itself, where the neo-Darwinian orthodoxy is today being challenged by complexity theorists s9Stuart Kauffman: At Home in the Universe (Oxford, UK: Oxford University Press, 1995) .. Rather than contingency and randomness, complexity theory highlights processes of selforganization in Nature which tend toward more complex organisms. If the “law of increasing complexity” is correct then intelligent life might actually be common in the universe. Either way, today it is simply not known.

“They can’t get here.”

Even if intelligent life is common, skeptics argue it is too far away to get here. Relativity theory says nothing can travel faster than the speed of light (186,000 miles per second). Lower speeds impose a temporal constraint on ET visitation: at .001 percent of light speed, or 66,960 miles per hour—already far beyond current human capabilities—it would take 4,500 Earth years for ETs to arrive from the nearest star. Higher speeds, in turn, impose a cost and energy constraint: to approximate light speed a spaceship would need to use more energy than is presently consumed in an entire year on Earth.

Physical constraints on inter-stellar travel are often seen as the ultimate reason to reject the ETH, but are they decisive? Computer simulations suggest that even at speeds well below light the colonization wave-fronts of any expanding ET civilizations should have reached Earth long ago s10Martyn Fogg, “Temporal Aspects of the Interaction Among the First Galactic Civilizations,” Icarus 69 (1987): 370-84.. How long ago depends on what assumptions are made, but even pessimistic ones yield ET encounters with Earth within 100 million years, barely a blip in cosmic terms. In short, ETs should be here, which prompts the famous “Fermi Paradox,” “Where are They?” s11Stephen Webb, Where is Everybody? (New York: Copernicus Books, 2002).

Additionally, there are growing, if still highly speculative, doubts that the speed of light is truly an absolute barrier s12J.Deardorff,B.Haisch,B.Maccabee,andH.E.Puthoff,“Inflation-TheoryImplications for Extraterrestrial Visitation,” Journal of the British Interplanetary Society 58 (2005): 43-50.. Wormholes—themselves predicted by relativity theory—are tunnels through space-time that would immensely shorten the distances between stars. And then there is the possibility of “warp drive,” or engineering the vacuum around a spaceship, enabling it to skip over space without time dilation s13H. E. Puthoff, S. R. Little, and M. Ibison, “Engineering the Zero-Point Field and Polarizable Vacuum for Interstellar Flight,” Journal of the British Interplanetary Society 55 (2002): 137-44.. Speculative as these ideas are, their scientific basis is sufficiently sound that research is currently being funded through the “Breakthrough Propulsion Program” at NASA. They may prove to be wrong or beyond human capacity. But if humans are imagining them just 300 years from our scientific revolution, what might ETs 3,000 years, much less 3,000,000, from theirs be imagining?

“They would land on the White House lawn.”

If ETs came all this way to see us, why don’t they land on the White House lawn and introduce themselves? After all, if humans encounter intelligent life in our own space exploration, that’s what we would do. On this view, the fact that ETs have not is evidence they are not here.

But is it? Again there is debate. The “embargo” or “zoo hypothesis” suggests that ETs might have quarantined Earth as a wildlife preserve s14John Ball: “The Zoo Hypothesis,”Icarus 19(1973): 347-49; J.Deardorff, “Examination of the Embargo Hypothesis as an Explanation for the Great Silence,” Journal of the British Interplanetary Society 40 (1987): 373-79.. Or, ETs might be interested in contact, but want humans to discover their presence ourselves to avert a violent shock to our civilization. Finally, even humans might not land on the White House lawn. In the popular science fiction show Star Trek, the Federation maintains a policy of “non-interference” toward lower life forms; might not real space-faring humans adopt a similar policy? Whatever the answer, debates about ET intentions have no scientific basis.

“We would know.”

The last skeptical argument is an appeal to human authority: with its panoptic surveillance of the skies the modern state would know by now if ETs were here. Of course, conspiracy theorists think the state does know, but there is no need to embrace this debatable proposition to call the skeptical argument into question. First, skepticism assumes an ability to know the UFO that may be unwarranted. If ETs have the capability to visit Earth, then they may be able to limit knowledge of their presence. Second, no authority has ever actually looked for UFOs, the effect of which on what is seen should not be under-estimated. Finally, in view of pervasive UFO secrecy more is probably known about them than is publicly acknowledged. This does not mean what is known is ET, but it could provide further reason to think so.

Given the stakes, ignoring UFOs only makes sense if human beings can be certain they are not ETs. We have shown there is more than reasonable doubt: the ETH cannot be rejected without significant risk of Type II error. What is actually known about UFOs is that we have no idea what they are, including whether they are alien; far from proving UFO skepticism, science proves its ignorance. With so little science on either side, therefore, the UFO controversy has been essentially theological, pitting ET believers against unbelievers. In this fight, the unbelievers have secured the authority of science, giving them decisive advantage. Their views are taken as fact, while those of believers and agnostics are dismissed as irrational belief. Since science does not actually justify rejecting the ETH, why would unbelief be so hegemonic? The UFO taboo is puzzling, we submit, and demands a deeper look at how its “knowledge” is produced.