site author: Anthony Wheeler email: firstname.lastname@example.org
I appreciate the opportunity to pass along my thoughts about your book, Lonely Planets, as I very much enjoyed reading it, as you provided an excellent overview of the current state of the subject.
In this age of narrow specialization and the proliferation of technical vocabularies virtually incomprehensible to outsiders, the role of science books written specifically for a general audience is absolutely critical. In order for scientific progress to make an impact on humanity, it must be translated by scientists into language and concepts that society can generally absorb. This may be very difficult, in some cases impossible, but even Wittgenstein attempted to express what he thought he knew.
The alternative would be to retain all scientific knowledge within the technical community, so that any relevant scientific advances inform applied scientists and engineers only, who then utilize this knowledge to improve medical treatment, transportation, communication and killing machines, keeping the rest of us scientifically ignorant. Your book goes a long way to help prevent this.
As a reasonably well-informed student of intellectual history, I believe that all thinkers must develop the capability to understand what they consider fundamental, and not simply accept the judgment of others, regardless of their authority. In my case, two of the most important scientific questions include:
1) how did life originate
2) how did biological forms evolve into ever more complex organic structures
The current neo-Darwinist view of evolution depends on random/chance-driven variation and natural selection to explain the existence of complex and diverse biological forms, as you point out:
It appears that the scientific community accepts the current view as definitive and final. If this so, the community will apply very little, if any, energy or resources towards understanding the nature of evolution. Students won’t select the topic for special study, career-minded academics will steer clear of the subject, and research grants will neither be applied for nor awarded. As a spokesman for the scientific community, you seem to reflect this perspective when you write:
I find the logic and the evidence of evolution to be completely convincing. [I agree – it seems clear that life evolved in ever more diverse forms over time, and that all living things spring from the same source, and share a common genetic structure.] A deep look at the world, digging into the rocks and dirt, shows a record of change and adaptation. The mechanisms described by Darwin, tweaked with 150 years of subsequent insights [neo-Darwinism], marvelously equip us to understand this process. Given variation, death, and heredity, there is no escaping that evolution will happen. Fossils and numerous other clues show clearly that it has. For the scientific mind, guided by Occam’s razor, there is no reason to invoke any other force in evolution, and the case is closed. [page 108]
“Given variation…” Unless I am mistaken, we don’t know how variation creates the complex structures that pervade the natural world. Through chance? Random mutations? Genetic drift? Sexual recombination? This is precisely the point where neo-Darwinism is the weakest, both theoretically and empirically. To my knowledge, we have no detailed theory or working model of how this might happen within the genetic structure of an individual organism or within a population, and what steps might incrementally create the complex organic structures and systems that pervade nature.
To consider the case closed, given our incomplete understanding of the process that drives speciation, seems a bit premature, and I am unwilling (or intellectually unable) to simply accept at face value your conclusions (or Mayr’s, or Dawkins, or Dennett’s, or Gould’s).
You demonstrate in many places the provisional nature of our current understanding, and it’s reliance on vast improbabilities:
These comments reveal the tenuous nature of our understanding of evolution. Science can only provide what you characterize in a different context as ‘historical observation’, as opposed to scientific explanation. That would make ‘closing the case’ at this juncture unreasonable.
But perhaps I don’t understand you properly (a common situation that must drive scientists crazy when dilettantes question their collective positions), as earlier in your book, you write:
The story goes as follows: Chemical evolution led inexorably to self-replicating molecules, which in turn evolved into the first primitive cells. Through Darwinian selection, these cells evolved into modern organisms.
This statement seems so reasonable and consistent with what we know about the natural world that we scientists accept it as true. The problem is, it’s difficult to prove. No one has succeeded in creating life from nonlife in the laboratory. (page 99)
You go on to say on the next page:
Though we don’t want to admit it, our belief that chemical evolution can lead to life is still an article of faith. Let’s call it informed faith…
Characterizing the current state of our understanding of evolution as “informed faith” seems perfectly fair and reasonable. If this attitude was widely accepted, it might lead to further research and critical debate. Why it doesn’t is partially explained by the political and cultural web that enmeshes the scientist:
The creationism-versus-evolution debate has unfortunately pushed science into a defensive corner from which we exude overconfidence, pretending to have certainty in places where we really have only reasonable inference. Instead of saying, in effect, “We have proof whereas you only have faith,” we could, more honestly, say, “At least our faith is testable in principle, and wherever tested has been borne out by observation.”
As a reasonable a-theological intellectual, with no academic career, and no religious affiliation or faith, I am confident that there is a perfectly natural explanation for some unknown creative element in biological variation—we just don’t know yet what it is. If that’s a real possibility, then the scientific community should get out of its defensive corner and openly admit as much. You put the case perfectly in a slightly different context when you write on page 261:
Looking at the history of science, how many times have we thought we had a complete understanding of some aspect of nature, only to find out later that we were looking at a tiny fraction of some larger truth?
The history of plate tectonics serves as a perfect example. Prior to the early sixties, nobody believed that the continents actually moved, yet within a decade, after scientists took the idea seriously, the notion was quickly proven beyond any rational doubt.
Darwinism has suffered a different fate. First systematically presented to the world in 1859, bolstered by the rediscovery of Mendal’s work some fifty years later, and further strengthened by the discovery of DNA in the fifties, neo-Darwinism has existed in its current form for at least five decades, and yet, it remains informed speculation at best, undemonstrated and unproven. While it’s possible that someday the current orthodoxy will gain empirical support, the more likely possibility is that neo-Darwinism stands as a “tiny fraction of some larger truth”.
Evelyn told me that you may write a book on evolution, so perhaps by acknowledging, if not emphasizing, the incompleteness of neo-Darwinism, you might contribute to a movement that will help free scientists and academic communities to question the current orthodoxy and study the subject more thoroughly, leading, if we are lucky, to the discovery of the genuine creative element within the process of evolution. Doing so might shed light on the original transition from the inorganic to the biological, which in turn may provide some insight into the basic question in your book: does life exist elsewhere? The following seems to indicate you may be open to this perspective:
It is certainly not immediately obvious that the beauty and complexity of life on Earth all came about through billions of years of random variation and selection. Our prescientific forebears can be forgiven for their intuitive inference that such a wonderful design requires a super-human designer. Science has given us reason to doubt this need, but science has also revealed the design to be far more intricate, complex, and finely tuned than anyone imagined hundreds of years ago. Modern thinkers, too, are reasonable to doubt that natural selection could come up with all this. If you have never, ever, doubted it, then you’ve never really thought about it, only accepted the ideology and authority of your teachers. Within each living cell, from the paramecia to paramedics, is a chemical factory far more complex and elegant in design than the most sophisticated chemical plant ever built by humans. (page 100)
It’s absolutely appropriate to doubt that natural selection came up with all this, because we have yet to explain or demonstrate in any credible manner how random variation and selection might have created the incredible diversity and complexity in the nature world, except in the simplest of cases. We don’t need God or aliens to explain evolution. What we need is to admit we don’t know how it happens, and treat the question with the respect it deserves, and energetically pursue a rational, empirical explanation for perhaps the single most significant question humans have yet to answer: how did life originate, and how has it evolved to the forms in which it exists today? The answer may ultimately be the most meaningful contribution science can make to humanity, and lead directly to your main concern: is there life out there, and if so, in what form and how pervasively?
Without understanding the origin of life, the possibilities range from life on earth being utterly unique, to being ubiquitous among the stars. In other words, we have no idea. To simply assume the existence of extra-terrestrial life, as you and many of your colleagues do (along with a high percentage of adults and children), based solely on the size and the age of the universe, disregards our collective ignorance relative to the origin of life and its subsequent evolution.
Your example of science predicting the existence of planets outside our solar system, and later finding them, may help illustrate my point. You present a credible model for the process that forms stars and solar systems. While complex in any particular case, we understand the principles involved. That being the case, we had every reason to believe planets orbit other stars. Finding them, while not a great surprise, provided gratifying empirical support for the theory.
In a similar manner, we collectively understand all of the physical, chemical, mechanical, electrical, hydraulic, organizational, political, economic, social and cultural elements required to build and fly a space shuttle. Our society can take the raw materials necessary to design, manufacture and operate complex systems, and manipulate them effectively until they work as intended.
Not so life. The only way we can create life is from existing life: either the old fashion way, where male and female mate and bring together egg and sperm, or through artificial techniques and manipulations, such as gene splicing or cloning. Nobody, to my knowledge, has ever created, from basic raw material (water, carbon, oxygen, etc.) a living thing, not even the simplest cell, let alone something as complex as a jelly fish, a dragonfly, or a lizard. Nor, to my knowledge, do we have the theoretical ability to do so, or even a basic model for how it might be done. Imagine for a moment, the following two possibilities* (assuming life originated on Earth):
1) life originated exactly once
2) life originated more than once
(*A third possibility would be that life originated in another form, but has since been destroyed, perhaps by carbon/DNA-type life forms. Or that life exists in ways we don’t currently recognize. Unless we find evidence of an alternate organic structure, these remain logical possibilities only, not empirical ones.)
If life as we know it, that is, life with a carbon-based DNA organic structure, originated exactly once, that would mean it was an incredibly rare event. Given the billions of years and the multitude of environments and opportunities over that time, we might be shocked at how amazingly lucky we are that it happened at all.
On the other hand, if life originated more than once, perhaps even tens of thousands of times, that means that there is exactly one structure suitable for life, the one we see today (carbon-based DNA), as every living thing, if I understand correctly, is built upon precisely the same organic structure.
If life originated exactly once on Earth, that implies that life may be very rare in the universe. If, however, life originated multiple times on this planet, than the opposite is the case, and if/when we find alien life, it will likely be based on a similar, if not identical, organic structure.
Now consider these two possibilities:
1) Biological life emerges naturally and routinely from the chemical realm, in the same manner that the chemical naturally emerges from sub-atomic physics. In other words, we don’t need any particular explanation for the existence of life, just as we don’t look for special explanation for the existence of gravity. It just is.
2) Biological life does not naturally emerge from the physical, inorganic world, but instead, exists as a special case, one that requires special explanation.
In the first case, life would exist almost everywhere, as a naturally occurring phenomenon directly related to the existence of energy and matter. In the second, the existence of life in any particular instance would be comparable to a particular work of art—it might or might not come into existence, depending on a very special set of circumstances.
One final consideration relevant to the distribution of life in the universe. There is some reason to believe that Earth, while perhaps not unique, is likely atypical for a planet of this size, and this distance from the sun (these being the three main variables you present as being relevant to the support of life, that is, the size of the planet, its distance from a star, and the type of star it orbits). In addition to these variables, we must consider the moon, plate tectonics, the atmosphere and the oceans as equally important, if not critical, to the existence of life.
In the late seventies I developed a particular “rare earth” notion based on a cataclysmic collision that occurred with Earth and another large object, resulting in the creation of our moon. (It was very gratifying to see you present this notion as generally accepted within the scientific community, vindicating an idea that my family has derided now for decades).
This same collision, or perhaps some other singular event, may have damaged Earth’s crust, resulting in moving plates and ocean basins. The moving plates drive high levels of volcanism on the planet, and the high level of volcanism is in part, if I understand correctly, responsible for releasing from Earth’s interior the various elements that make up Earth’s oceans and atmosphere.
This insight came about by comparing Mars and Earth, and noting that Mons Olympus is so tall because it sits unmoving over a hot spot on the surface of Mars, a planet without moving plates (and with no oceans and very little atmosphere). Hawaii, on the other hand, demonstrates what happens when a plate passes over a hotspot—you get the creation of one volcano after another, but none of them excessively tall. Neither Mars nor Venus, the two planets most comparable to Earth, are tectonically active, and this may imply an element of geological uniqueness to Earth.
If, for the sake of discussion, you take the following options from the previous three scenarios, and add a fourth consideration, you may come to the conclusion that ET life is far less likely than commonly assumed:
1) Life originated exactly once (on Earth)
2) Biological life does not naturally emerge from the physical, inorganic world, but instead, exists as a special case, one that requires special explanation
3) Earth is atypical
4) Intelligence has evolved exactly once on this planet (unless Douglas Adams is right, and humans rank third after white mice and dolphins). This might suggest that biological intelligence is uncommon. Instead of assuming the inevitable evolution of intelligence given the presence of life, we may have to assign a low probability to its development within a given biosphere.
If we reconsider the Drake equation using this set of assumptions, we might adjust the relevant variables in this way:
ne goes from 1-5 to 1/10,000 (Earth is atypical)
f1 goes from 1 to 1/100,000 (life is very rare)
fi goes from 1 to 1/100 (the evolution of intelligence is not assured)
R* = 5 (middle of the range)
fp = .8 (I actually think more stars will have planets, so increased this from .5 to .8)
fc = .5 (this seems reasonable)
L = 108 (let’s assume the high side)
If I did my math correctly, this results in a .002 chance that even one intelligent civilization exists in the galaxy that can communicate with us. The point here is that it doesn’t take too many improbabilities to overcome large numbers of stars and long stretches of time.
Today we have no empirical proof that life exists elsewhere, and some reason to believe that it doesn’t exist anywhere but Earth (the failure of SETI, the deadness of Mars and Venus). The case of extremophiles doesn’t help your case, because it only demonstrates how life can adapt, not necessarily under what conditions it can originate.
But this remains highly inconclusive. It’s unlikely that we will ever prove that life doesn’t exist elsewhere, given the impossibility of ruling out every possibility. All we can ever prove is that life exists elsewhere (if it does exist elsewhere) by finding it (or having it find us).
You seem absolutely convinced that life exists elsewhere. Aside from the unscientific bias (which you address, and fully acknowledge the professional risk that accompanies such an attitude), believing so fervently potentially impacts your professional credibility, and the effectiveness of the scientific community as a whole. Consider the alternative for a moment. What if it turns out, in the coming decades or centuries, we determine that life on Earth is extremely rare, if not utterly unique. To me, that would be as shocking and meaningful as finding fully sentient aliens, and you don’t even consider it an empirical possibility.
And besides, why are we so anxious to encounter intelligent extraterrestrial life anyway? As Guy so aptly screamed in Galaxy Quest, “Have you watched the show?!” Any encounter is unlikely to turn out well. In fact, it’s would likely be a disaster for either them, or for us. We know half the equation—the human half:
It wasn’t Hitler, the Nazis, or even the Germans that perpetuated the holocaust: humans did.
Look what happened when the Europeans arrived in the New World; Native Americans suffered devastation, disease, physical and cultural dislocation, and all at the hand of beings little different from themselves. We don’t even respect the creatures that reside on Earth: we capture and kill dolphins, for example, and experiment freely with white mice. If we encounter aliens and are the least bit provoked, we will destroy them, if we can, because it won’t be rational scientists deciding policy, nor any other reasonable element of society. Some of the brightest scientists in history couldn’t stop the use of nuclear weapons in 1945, nor could the flower children halt the indiscriminate bombing of Hanoi and Cambodia during the Vietnam War.
And God help us if the aliens are technically superior to humans. A simple virus, biological or computer, will unlikely stop them, if we have something they want. We assume that moral superiority will accompany technical superiority, and I am not sure that’s a reasonable assumption. The odds of gaining any benefit from an encounter are vanishingly small, so why long for it? The best we can possibly hope for is passive indifference, when the time comes, as it would be a miracle if we gained any genuine benefit without something precious being destroyed. Es kann gut ausgehen nicht.
To be more optimistic would require the mass conversion of humans to a compassionate faith, a conversion I believe impossible, given the biological nature of the species.
(By the way, the core of Buddhism is radical negation, not compassion. The Four Noble Truths demand the acknowledgment of pervasive pain, pain driven by desire, with the intent to eliminate all desire [including a compassionate desire to do good] and thereby eliminate pain, allowing one to cruise the eight-fold way to enlightenment. While to outward appearances Buddhist behavior may look like compassion, it might be better characterized as cultivated indifference.)
Concerning the style of the book (and these comments are trivial compared to earlier topics) I would encourage you to make it a bit more challenging by raising the level of discussion a notch or two. While I applaud your effort to relate to the common folk, I would predict that few people reading your book need a foot-note defining plate tectonics (p. 93). And your second note on page 109 has to be meaningless for anyone who doesn’t know your father, and what he has done. Although some grounding in your individual humanity is necessary to make the connections, the fact is, most of us reading your books are most interested in the content of your mind and not your iPod. It’s really just a question of literary balance, and I thought you could have injected more scientific complexity and less personal anecdote.
Nevertheless, Lonely Planets represents a great effort to apply rational scientific understanding to a topic shrouded in New Age cultural mystic and rampant speculation, and I fully appreciate your willingness to delve into every facet of the subject, both personally and professionally, and deliver such a comprehensive survey. Very nicely done.