Why Has There Been No Contact With Aliens?
August 2, 2009 27 Comments
The explanations offered can be broken down into five basic possibilities:
1. There are no aliens
2. We are too far away for contact
3. Humans have failed to recognize signs of alien activity
4. Aliens choose not to contact humans
5. There is limited, secret contact between aliens and humans
1. There’s Nobody Out There
The idea that there is no intelligent life in the universe except human beings is to me the most radical hypothesis. 20th century science has established that the universe is a very big place, unimaginably huge. There are billions of stars in our Milky Way, which appears to be a fairly typical galaxy. Cosmologists still have not really been able to count how many galaxies there are. Recent discoveries have confirmed the long-held theory that many of these star systems have planets, and they may have moons and comets and other structures capable of supporting life as well. Contemporary biology has established that life can thrive in a variety of circumstances, such as under the massive pressures at the bottom of the oceans, in the fiery, sulphurous rims of volcanos or in frigid artic chill. The vast expanse of the universe offers a lot of space and a variety of conditions for life to develop.
Pre-Copernican thinkers, many of whom saw the earth as the center of the universe and could not conceive of the sun as only a minor star in a minor galaxy, could be forgiven for not being able to imagine other life forms on other planets (although actually a few did). Those who today know of the vastness of interstellar space and the variety of life forms the simple earth has produced, and still proclaim that life on earth is unique reach new heights in arrogance, and new depths in poverty of imagination. It is, of course, logically possible that this huge cosmos is without extraterrestrial life and the process that led to life on this planet has never been repeated anywhere in the billions and billions of star systems and billions of years of existence. It just seems extremely unlikely that the earth could be teeming with life and the same process be absent in the rest of the unimaginable reaches of space.
Only marginally more plausible is the position that lower forms of life may be common througout the cosmos but that intelligent life is unique to earth. It is probably true that just as on earth, one-cell organisms, bacteria-like organisms, and other simple life forms are more common throughout the cosmos than intelligent life. On many planets or other systems life may have evolved, but not intelligent, self-consious life. Perhaps the vast majority of life-bearing systems in the cosmos show no signs of intelligence.
But the same argument as to the very existence of life also applies to the development of intelligent life. If life is at all frequent, the probability is that in at least some life-bearing systems, intelligence has also evolved. To take a random number, if there were a million life-bearing systems in the galaxy, if only 1/10 of 1% of those have developed intelligent life, that would mean there are 1,000 systems with intelligent life forms in this galaxy alone. Again, the universe is a very big place, offering a vast set of opportunities for life, and thus intelligent life, to emerge.
2. Long Ago and Far Away
Another possibility is that although there is almost certainly intelligent life somewhere else in the cosmos, it is too far away in space and/or time to establish contact or communication. This view is held by many eminent scientists. The argument that intelligent life is likely somewhere in the cosmos exactly because the universe is a big place can be turned around to say that the vast majority of life forms would be so far away as to be unable to contact the human race in any practical manner. Some of the light we see in the night sky has taken billions of years to reach us, even though it is traveling at 186,000 miles per second. Even the brighter stars in the sky are hundreds, thousands, or more light years away from us.
Contemporary physics says that the speed of light is an ultimate cosmic speed limit–that nothing has ever been discovered that travels faster than the speed of light. If true, this puts quite a damper on interstellar travel. Traveling at close to the speed of light, it would take 4 years to reach the nearest star to the sun. Most stars in the galaxy would take many human lifetimes to reach and that does not include any trip back. Communication, as well as travel, is also bound by the same limitations. Radio, TV, and other human electronic communication have been skipping into outer space for a century at the speed of light, but they have traveled only a small faction of the length of our galaxy, which is only a tiny corner of the cosmos.
Time is also a factor making living contact between humans and any particular alien civilization unlikely. The universe is not only very large, it is also very old. Contemporary cosmologists currently estimate the age of the known universe as 10-15 billion years. An alien civilization could have arisen on a nearby star billions of years ago, flourished for millions or even billions of years, and then died out before intelligent life appeared on earth. Or life that evolved in a nearby star system could have moved on to better environments on other systems further away in the galaxy or beyond, leaving no laggards behind. It is certainly possible that the first evidence humans discover of intelligent alien life may be the ruins of a long gone alien civilization.
On the other hand, life may be in earlier stages of development in one or more nearby star systems, where evolution may be reaching for intelligent life forms who have not yet arrived. Ironically, human colonization of other planets may forestall the evolution of higher alien life forms.
Virtually all science fiction which portrays contact with aliens deals with the problem of the size and age of the universe by positing some kind of faster than light travel. Star Trek’s “warp drive” or “wormholes” would be necessary for human beings to travel or communicate any appreciable distance from our sun, more than metaphorically around the block of our own galaxy, much less beyond our “little” galaxy. Many working scientists argue that such hypotheses make nice fiction but bad science.
There are basically two answers to this objection. One is to argue that the speed of light may not be an ultimate cosmic limit–that the science fiction writers have a more accurate view of future technology than the physicists. Wormholes and even hyper-light movement have some basis in theoretical physics although they are not supported by any real empirical evidence. Unfortunately, the theoretical parameters of wormholes and such make them unlikely places for humans to be traveling.
However, rather than looking at contemporary speculation about exotic physical phenomena, I believe the best approach is to maintain historical perspective and humility. Less than a century ago, physicists were totally unaware of the theory of relativity which produced the equations which they now insist mean that faster than light travel or communication is totally impossible. Less than a century ago, cosmologists had literally no idea of the vast size of the cosmos. It is a kind of ahistorical arrogance for people today to assert that although we have only comparatively recently discovered the theory of relativity, we now have reached a nearly complete understanding of the physical processes of the universe and can say with assurance that faster than light travel is a physical impossibility.
Another way to counter the contention that intelligent life exists but is too far away for us to contact is to argue that the universe, or at least our part of our galaxy, could be so full of life that relatively nearby systems would be life-bearing. Life could be so densely distributed across the universe, or at least in our local area, that there are life-bearing systems not so far away. If life is common, then we don’t have to travel to the furthest reaches of the cosmos to find it.
This is one reason why the seemingly trivial arguments about whether there are bacterial or other simple life forms on Mars or other planets, moons, or comets in the solar system is so important. If even primitive life is found within the solar system, that would increase the probability that life is densely distributed throughout the cosmos and thus the likelihood that intelligent alien life might be found on relatively nearby systems.
3. Seeing the Signs
But if intelligent life is relatively close to us, then the question becomes why have we not detected it by now. Ever since the invention of the telescope, human scientists have been scanning the heavens with increasing intensity. With the discovery of other galaxies and the dawn of the space age, human scrutiny of outer space has further deepened. Now there is even the deliberate Search for Extraterrestrial Intelligence (SETI) project. Why haven’t we found any convincing signs of alien intelligence?
One possibility is that we are just too dumb to recognize the signature of alien civilization. Think about relatively intelligent life right here on earth. It is only in the past few years that human scientists have begun to comprehend the true intelligence of apes, dolphins, and other animal species. Only recently have we come to know that apes can learn hundreds of words in human sign language and even teach each other the signs that they learn from humans. Rigorous scientific observation has shown that apes, dolphins, and perhaps other species can count in single digits and even perform simple arithmetic tasks on small numbers.
But only a decade or two ago most human scientists dismissed with derision anyone who even hypothesized that any animals would be capable of such feats. Scientists, trained in materialistic skepticism, preferred to interpret animal behavior in terms of physical instincts rather than internal intellectual processes. Animals have not become more intelligent in the past decade, rather humans have only recently learned to recognize the intelligence that was there all along.
Aliens may be as intelligent as humans or more intelligent than humans. The greater problem in discovering alien intelligence may well be in recognizing alien forms of life at all. Alien life forms may well be radically different than humans. Alien and human life processes may be so fundamentally strange to us as to make it difficult for humans even to recognize aliens as life forms. Popular mythology has gone a long way from the simple humanoid aliens of early science fiction. But even green reptiles with three eyes, four fingers, and flexible tails or malignant flying insect armies with laser guns are based on a carbon-water model of life. Almost all life on earth has evolved from early organisms with a biochemistry based in carbon and water, and there are good reasons to think life on other systems could have a similar biochemistry. The ability of the carbon atom to bind in complex ways with other elements, the ability of water to dissolve a wide range of chemical compounds, and the relative frequency of the elements of hydrogen, carbon, and oxygen throughout the universe mean that carbon and water are an excellent and widely available basis for the emergence and evolution of life forms throughout the cosmos.
But carbon and water are not the only physical basis for life. Even here on earth sulfur based life forms have recently been found living in the searing heat around volcanos. Perhaps the most interesting aliens in the science fiction pantheon are Robert Forward’s cheela, who evolved on the surface of a neutron star with a biology based on nuclear forces. Larry Niven imagines a race of “outsiders” who live in the thin cosmic dust which lies in the vast reaches of space between galaxies, which is actually most of the physical space of the universe. Forward’s cheela and Niven’s outsiders are just a couple of speculations on the wide panoply of life-producing possibilities the cosmos provides. The capability of the cosmos to produce life may well exceed the limits of the human imagination, just as the very size of the cosmos confounds the human intellect.
Forward’s cheela raise another interesting problem in the recognition of alien life and intelligence–scale. The cheela are tiny compared to humans, not just diminutive like Lilliputians but microscopically small.
At the other end of the problem of scale, aliens might be so huge and their biology so “alien” that humans cannot recognize them as alive. The movie Animal House has one precious scene (which is never shown on TV anymore because it involves marijuana use), in which a stoned student imagines the solar system is one molecule in the fingernail of a galactic-sized superbeing. While that is a rather naive statement of the issue, it reflects the possibility that alien life is so large and based on such a different biology than humans that we could not recognize it as life even if we ran across it in our cosmological surveys.
SETI scientists have tried to overcome the issue of truly alien biologies by searching for radio signals and other signatures of technological civilization that they presume are universal or at least common among advanced life forms. And it is true that carbon-water life forms, such as four fingered reptiles or intelligent insect-like collectives of earth-like scale, might well develop radio communication or other technologies similar to those of humans. It may well be that technology is less flexible than biology, so that species with very different origins might have similar forms of communication or similar patterns of heat emissions from population centers.
But it is also possible that highly advanced alien civilizations either communicate without technological aids or with technologies so advanced humans could not even recognize them as technological artifacts. Again, an analogy from life on earth illustrates the problem. It is only recently that humans have recognized that many ocean creatures are highly intelligent even though they do not produce anything we would recognize as technology. Biologists who have studied dolphins argue they are at least as intelligent as apes. We have also discovered that whales communicate across ocean lengths with incredibly complex songs. To this day human biologists are not really sure whether the complexities of whale song communicate simple information like location and identity or whether whale song contains massive amounts of information about emotional states, environmental conditions, social events, individual and social histories, etc. Whale song may communicate as much or more than human speech, but humans will never know until they are able to decode it. It is hard for humans to imagine a form of non-technological communication that reaches across oceans, but such a form of communication exists here on earth. Alien species may have developed ways to communicate across interstellar space that we could not recognize as “technological,” or even recognize as communication at all.
Carbon-water chauvinism and the particularities of how human life developed on earth may be blinding us, leaving us unable to recognize signs of intelligent aliens in our galactic neighborhood. We are no longer foolish enough to be looking just for little green “men,” but we may not yet be wise enough to read the signs that are before our eyes. The same may be true for alien civilizations of roughly equivalent development as humans. They may be near enough to have evidence of humanity but be unable to read the signs well enough to see us.
4. Indifference or a Prime Directive?
However, even if humans are missing signs of alien intelligence, one might think that if highly advanced aliens (even non-carbon-water aliens) wanted to reach us, they could learn enough about human biology and communication to get a message through. While humans have not yet learned to understand whale song or ape language, as a more advanced species, we have been able to find ways to communicate with these species when we choose to.
But perhaps nearby intelligent aliens choose not to contact humans, even though they are aware of the existence of the human race. Perhaps we just are not very interesting to them. Maybe they are just as self-absorbed as most humans are or even more self-absorbed and simply not particularly interested in other forms of life. Or more likely, advanced aliens view us much like we view ants–as a somewhat interesting life form but certainly not intelligent or sensitive enough to be worth trying to communicate with.
Perhaps advanced aliens are observing us from a distance but choose not to interact with us. There could be several reasons for this.
Perhaps they think contact is too dangerous or troublesome. Perhaps they judge humans as not worthy of contact not because of our intelligence but because of our unethical behavior. Human wars and other acts of barbarity may convince advanced aliens that we could pose a threat to cosmic order. To use a Star Trek analogy, humans may be the Klingons of intelligent species–a people so steeped in war, cruelty, and xenophobia as to be poor candidates for an interspecies federation. Aliens may see our treatment of other semi-intelligent species on earth as proof we are not ready to deal “humanely” with extraterrestrial species. Our treatment of our own planet may convince them we lack the ecological consciousness to be intergalactic partners. Because of our “sins” the human species may be being held in a biblical “bottomless pit” of exile from other intelligent life.
Or perhaps it is not so much human beings who are dangerous but rather the act of physical contact that aliens avoid. Other experiences with interstellar travel may have made advanced aliens highly wary of disease. Aliens may fear a kind of “andromeda strain” plague could be the primary consequence of interspecies contact. Maybe they do not so much fear the direct influence of human depravity on their society as much as the distortion of their society and human society that prolonged contact with a much less developed species might induce. Think of the impact the discovery of the “new world” and the contact between more technologically advanced Europeans and less technologically advanced Native Americans had not only on the Native Americans but also in spurring European imperialism and intensifying rivalry, conflict, and war between European nations.
So advanced aliens may be aware of the human race and even observing our development, but maintaining some kind of “prime directive” not to make contact until certain conditions are met. They may be protecting themselves, or they may be protecting us, or they may be doing both. They may not feel that humans are ethically, socially, or scientifically ready for contact yet.
Perhaps aliens are waiting for the human race to pass a kind of intelligence or ethical test. They may be ready and willing for contact but only if we solve their puzzle or only if we show that we too are ready and willing (as an entire species, not just a few individuals).
5. Limited Contact: The X-Files Scenario, with or without the Paranoia
Then, of course, there is the X-Files scenario–that there has been some form of limited contact between aliens and a select few human beings. The more paranoid of these scenarios I personally find highly unlikely. It is true that if hostile aliens wanted to eliminate the human species and steal our planet or had designs to use us as slaves or cattle, human collaborators could be useful. But at least some of their human collaborators would almost certainly have second thoughts and tip the rest of us to the existence of hostile alien powers. A conspiracy large enough to be of much use to alien conquerors in pacifying the global population would almost certainly leak, backfiring on not only the aliens but also the human traitors. Limited spy or guerilla missions might be successful, but a broad, X-Files like conspiracy could never work.
There are more benign limited contact scenarios however. Perhaps aliens are in contact with a small minority of humans but for altruistic or at least non-sinister purposes they want to stay concealed from the general population. The previous section provided several reasons why advanced aliens might choose to observe the human species from afar but not announce their presence to the general human population. However, they might seek the benefits from very limited contact with humans in order to study us more closely. These contacts would have to be very rare and well-disguised, otherwise, as noted above, they would leak to the general populace. Aliens would have to be particularly careful not to leave any obvious physical evidence of contact. Humans who wanted to reveal their experiences of contact would then be in the position of Jodie Foster in the movie Contact–unable to document their personal experiences.
In the most benign of the limited contact scenarios, aliens might even be guiding human development from a distance, perhaps even preparing us for eventual contact. The problem with that scenario is similar to the old problem of the theodicy in theology. The theodicy asks if there is an all-powerful and all-merciful God, why is there so much evil in the world? Similarly, one would have to doubt the benign alien guidance scenario because it would raise the question, if advanced aliens are guiding our development, why is the human race so fucked up? The benign guidance scenario also suffers from the same problem as the X-Files scenario. One would think that alien intervention in human affairs broad and deep enough to actually shape human history would be impossible to effectively conceal.
Views of the Universe, Views of Life
In the end, the issue of the existence of alien civilization is not a question only for science. Science can inform our search for extraterrestrial life and confirm or invalidate a few hypotheses about the particular forms alien life might take. But scientific materialism and skepticism are antithetical to the kind of imaginative creativity it takes to envision the true place of humanity and other species in the cosmos. Perhaps someday contact with aliens will be firmly established and thus no longer in question. Until that time, humans will continue to speculate about the possibilities and probabilities of intelligent aliens.
In the absence of clear scientific evidence, science fiction probably can tell us more about potential contact with aliens than science. But the conventions of Hollywood and contemporary science fiction also often militate against greater understanding of the real possibilities of contact with aliens. Humanoid aliens make better TV and movies than truly alien biologies. Special effects of malignant alien warships give a kind of adrenaline rush that could never be produced by a more realistic portrayal of scientists trying to decode alien communications or philosophers musing over the possible thought processes and intentions of species evolving from a different natural history than ours.
To think clearly about the potential of contact with aliens takes more mental discipline than is typical in Hollywood and more imagination about life than is typical of scientists trained in professional skepticism. In the end it is not that different than thinking deeply about the ultimate potential of humankind and the place of humanity in the universe. It has its own kind of subtle, sublime rush.(Source:http://www.geocities.com/dflorig/00noalienspage.html)