As is the case with a great many folks.  I’m referring to A little pessimism about Extraterrestrial Intelligence over at Pharyngula.  While he assumes Carl Sagan missed the point on the question of whether or not there is intelligent life out there, I think it’s PZ who missed the point due to some very unfortunate assumptions on his part.  Let me preface this by saying he is a biologist who spends significant amounts of time studying evolution.  It is by no small stretch of the imagination that his experience and career in that regard play a major role in his view of the topic.

When speaking in terms of advanced alien life for which we might eventually see clues writ in the heavens, there are only two words that define the debate: advanced and alien.  This speaks to the question of finding radio signals, seeing spaceships, and locating technological structures in space, not to mention every other aspect of what would be involved in discovering extraterrestrial intelligence.

The primary flaw in PZ’s argument is the assumption that evolutionary evidence on Earth somehow dictates the dynamics of evolution everywhere.  He claims intelligence is seen in only one species on our planet out of billions of years of evolution and innumerable forms of life.  Such a profound error in logic is meaningful because we are a single planet with a very specific environment wherein life developed and evolved.  As is normally the case in such discussions, most humans, PZ among them, are simply unable to see beyond their anthropocentrism.  That is, human experience and knowledge is used to define all possible experience and knowledge, a maneuver which places Home sapiens in the preeminent position of outlining all possible life and evolution.  Is it too far fetched to consider non-carbon based life?  Is it too far fetched to consider another planet could well have given rise to multiple intelligent species?  Is it too far fetched to consider Earth is the exception in that regard?  Is it too far fetched to think life on our planet has followed an evolutionary path that is the exception rather than the rule (e.g., the multiple mass extinctions here are not as common elsewhere)?  Attempting to use our tiny sphere of experience as the only measure by which life might develop in a near infinite universe is, to me anyway, indicative of an extreme lack of imagination and an unfortunate level of anthropomorphic blindness.

He  justifies this position by claiming: “The universe doesn’t seem to like smart guys. We happened once, and what’s more, we seem to be teetering at the end of one long chain of improbable events in the history of one marginal set of lineages, of which most of its members are in decline.”  This speaks directly to anthropocentrism and anthropomorphism.  It is one of the worst legacies of humankind that the entire species is unable to see the universe in any way other than as defined by our own species.  When we speak of emotions in animals, most claim they do not have them because they do not express them precisely as we do.  Others claim they do have them because they observe something in the animal that is similar to human reactions.  Both approaches are flawed (one more than the other) and exemplify precisely why the idea of extraterrestrial intelligence so often is misinterpreted and misrepresented.  The general basis of such illogic stems from a simple flaw: humans cannot think about it without forcing the premise to comply with human experience and knowledge.  It is as though the word ‘alien’ is spoken yet ignored, for its very definition negates the point of view being espoused.  Amazingly, even PZ acknowledges this problem but ignores his own application if it when he says, “If one looks at the history of the biota here without the usual self-important vanity, it’s the bacteria that are the major success story, and the last big innovations that fueled an explosion of new, successful species were the flowering plants and grasses.”

Consider for a moment the argument that a proliferation of intelligence in the universe (as indicated by the Drake Equation) means we should be inundated by signs of those intelligences.  Some examples given for the equation’s failure are the lack of radio signals from space, the lack of artificial structures in space, and the lack of spaceships zooming about the galaxy.  Each of these “flaws” is a flawed argument unto itself.  Let’s consider them individually.

Radio is a human invention.  I realize the EM spectrum is a structure of the physical universe, but our use of it in this manner is wholly a manmade invention based on our limited understanding.  It could be that such technology is a given in the primitive stages of all intelligences, but it is impossible to say that with certainty.  Likewise, it is completely false to assume such a thing and to use the lack of such signals as an indicator of the lack of intelligent life.  Our technological innovations are based solely on our evolution and planet’s resources, and they are limited only by our imagination and current stage of intellectual development.  An alien species might well be using something completely different.  Consider for a moment the Star Trek universe and its use of “subspace communications” for intragalactic communiqués.  In that realm, the technology uses a completely different universe through which to send information since it provides higher speeds than would be available in our own.  Based entirely on that invention of human imagination, there is no reason to believe our planet isn’t already surrounded by the equivalent of a full spectrum of television and radio broadcasts that we are as yet unable to hear or see.  Our failure to find them does not mean they aren’t there; similarly, our not finding them does not mean they are there but are using a technology we can’t detect.

As we peer into the near infinite expanse of space and come back with magnificent photos of fantastic events and natural structures, what we have not seen is a single Dyson’s sphere or a space station orbiting a distant star or a galactic gas station and rest stop for weary travelers.  Barring our desire to apply our own technology and solutions to what others must do, does the lack of such evidence mean such structures are not there?  Or could it mean they are hidden from us?  Even more likely, and as we have learned with the discovery of hundreds of extrasolar planets, does our primitive technology currently hinder us from directly observing such things?  Finally, has it occurred to anyone that space is so massively large that what we have seen of it is only the tiniest fraction of what’s out there?  It is of no present consequence that we’ve not laid our eyes upon artificial structures in space.  There are a myriad of reasons why this is true, and there are a myriad of reasons why it may always be true, not the least of which is our inability to see and record anything more than the equivalent of the head of a pin when compared to all there is to see.  Remember, this is the same reason why searching for near Earth objects (like asteroids that might pose a risk to us) is such a daunting task: there’s a lot of territory to cover and it’s impossible to look both near and far when viewing any one spot.  Taking a photo of space only reveals what’s in focus and not what lies beyond or what exists nearer the viewer.  This is simple optics in play, except with space, it’s on a scale unimaginably large and expansive.

Our species has been watching the heavens for its entire brief existence.  Writs of such observations date back as far as recorded history (including cave paintings).  Irrespective of the UFO phenomenon (which is neither here nor there for this discussion since it proves nothing), we have seen no definitive proof of spacecraft flitting about as aliens cruise the Galactic Route 66.  Does not having seen them mean they are not there?  No.  The primary reason is distance: the universe is vast and we are so small, so there’s no reason to assume we should see them even if the heavens are full of such things.  It’s possible no one has arrived in our neighborhood.  It’s equally plausible they are intentionally avoiding us.  Again as probable is that they cannot be seen by our primitive technology.  Think about our own use of stealth and the new cloaking devices we have invented.  Now, consider those are based on our intelligence and our experience.  What might aliens use to hide themselves from prying eyes?  We simply can’t imagine lest we negate the very definition of the word ‘alien.’  It’s possible an armada of alien craft that we are unable to see or detect in any way already surrounds our planet.  We can’t be certain Earth isn’t being treated like a galactic Petri dish where alien species can watch the simple life forms develop in hopes of better understanding their own evolution and history, if not something akin to the human tendency to want to study everything that’s different and unknown.

A critical aspect of the entire discussion is this: Is it compulsory for us to recognize alien life and technology if we see it?  The answer is a resounding “No!” due to the very nature of alien life.  We build ships made of metal and wood and fiberglass and a plethora of natural and unnatural materials.  Must we assume all life would do the same?  If an alien civilization’s technology was organic/biological in nature, would we even recognize it as technology if we saw it?  And what if an alien race built vessels that resembled natural structures such as comets and asteroids simply out of an abundance of caution or fear?  It is impossible to imagine all the possibilities for these things because we must draw on our own experience and knowledge.  As we continue unraveling the secrets of the cosmos, we learn quickly that what we know barely scratches the surface of what there is to be known, and even then, we generally come up with more questions than answers.  It generally seems a bit silly to explain away what might be when staring at the overwhelmingly diverse life here on our own planet.  Imagine what could exist out there where things are quite different and limited only by the universe itself.

PZ failed to consider one simple reason for our lack of contact with alien life: the real-world equivalent to Star Trek‘s Prime Directive.  Idealism aside, that rule and its many variations represent a simple cause for the effect we’ve thus far observed.  It could be that aliens do not meddle with such primitive species but instead leave them to develop on their own.  It’s possible our own barbaric nature, having been observed for centuries, is cause for alarm and sufficient reason to avoid us altogether.  As Julian May hypothesized in her “Intervention” series, alien life could have a common denominator that defines when they finally make their presence known.  (In that series of books, it was the formation of advanced mental abilities and the use of those abilities to reach out into space.  That does not negate it being something entirely heretofore unconsidered, even if it’s as simple as the development of interstellar spacecraft.)  We might also be witnessing the result of extreme xenophobia in alien races.  It’s possible it’s the result of our universe’s version of the Borg waiting in the wings to consume any civilization that pops up on the radar.  It might be a dangerous place out there for all we know; that seems reason enough to keep your head down and mouth shut.  Perhaps we’re nothing more than resources to be culled at an appropriate time which has not yet come to pass.  All of these are sufficient causes; the very idea of alien life means it’s more likely to be something we can’t imagine.

At the end of his post, PZ finishes by listing four additional reasons he doesn’t believe extraterrestrial intelligence exists or will be found.  The first is quite sound as its conjecture as to the longevity inherent in intelligence.  The second is equally sound as conjecture regarding the specialization of intelligence once it reaches a certain point (e.g., once they have television or its equivalent, the outward focus dims and stagnation sets in, and this has the unfortunate side-effect of rendering most civilizations boring homebodies; this premise would make humans an exception since we continue to look outward even with plenty of diversions here at home).  The third, a premise regarding local opportunities (e.g., once a species gets into space, they get tied up exploring their local neighborhood and never get any further) is only partially sound.  We can never know how much of a quest for knowledge any one species has until we meet that species.  If humans are any indication of the thirst for exploration that could exist in others, the extent of possible life in the universe invalidates the argument since there would still be many races out there who would never be satisfied with what they had in their hands, so instead they’d constantly want to push a little further and a little further to see what was just beyond their reach.  The fourth is a complete fallacy, which falls back on the anthropomorphism and anthropocentrism displayed throughout his discussion (the same traits he accuses others of demonstrating without realizing his own use of the same flawed logic).  He assumes life cannot survive in space and states it thusly: “Space is for spores, not people.”  While that’s entirely true, it has nothing whatsoever to do with the question of extraterrestrial intelligence; it is only related to human intelligence and life on Earth, and even so, it’s based entirely on our current level of technology.  It is a blatant error to consider that all life must find space unwelcoming and uninhabitable (what if there is life born in space that considers that home?).  It’s equally false to assume a greater level of technological advancement, not to mention need, will not override those very concerns for our own species.  One need only look at the International Space Station for an example of why the argument is moot.

I thoroughly enjoyed seeing PZ’s view on the subject and did walk away from it with a greater understanding of some of the evolutionary considerations in the debate.  Regrettably, most of his approach to the topic rang hollow due to what seemed an inability—oh, and how I hate clichés!—to think outside the human box.  His knowledge of evolution as a process is very applicable; his knowledge of evolution specific to our planet is not.  Attempting to push both human knowledge and human experience into the cosmos in such a way negates the very idea of alien life by assuming it must be like us in some way, whether that be carbon-based, having followed a similar evolutionary path, or evolution not favoring the development of intelligence, not to mention a litany of other false conclusions.  While I am marginally disappointed in what can only be seen as a lack of imagination on a topic which defies definition on and in our terms, I’m equally pleased to have walked away from his post with a few considerations which I’d not yet taken into account.  Nevertheless, his arguments are seriously flawed and focused too heavily on humanity.  He fails to see the wonder and beauty of possibilities inherent in such a profoundly vast universe.  If all we know is all that is possible, we limit the limitless in ways I’m certain it will easily refute.  Whether we’re still around by then is another question entirely.

Let me finish by bastardizing something he said that I quoted earlier in this post: If one looks at the universe without the usual self-important vanity, it’s diversity that is the major success story as evidenced here on our own planet, in our own solar system, and throughout our own galaxy; the biggest innovations it has to offer are those we cannot imagine given our extremely limited understanding of the tiny fraction of it we’ve already observed.