November 8th, 2010
I see that we have yet another “Aliens attack the Earth!” movie coming out. This is a reliable Hollywood genre, providing lots of drama and plenty of room for action and computer-generated graphics. No doubt, we’ll see a new entry in this field every few years. We must, of course, remember that this is just Hollywood at work; it has nothing to do with reality. I did notice some months back a squib about a scientist warning that perhaps we shouldn’t be sending messages into space, on the off chance that some nasty aliens might stumble upon such messages and follow them back to earth for a tasty lunch. This is nonsense, of course; if ever any aliens do manage to reach us -- an extremely unlikely possibility (which I’ll explain another time) -- it is almost a certainty that they will be morally far superior to us.
How can I be so certain? Elementary, my dear reader. The reasons arise from fundamental considerations about the concentration of negentropy necessary to accomplish interstellar travel. I’ll present the argument at two levels: simple-minded aliens-as-humans-with-funny-heads, and aliens as negentropy-collecting machines.
The simple approach: aliens like us
Let’s turn the tables around and imagine what it would take for earthlings to send spaceships to other planetary systems. Obviously, we don’t have the technology to pull this off. We’ll need to make a lot of progress in order to reach that point. But that raises an interesting question: What is progress?
We usually think of progress in technological terms: walking to horses to chariots to railroads to automobiles to airplanes to rocket ships. That’s progress. But there are other forms of progress as well. How about economic progress? The amount of wealth commanded by the average earthling today vastly exceeds what our ancestors had. That’s progress. Or how about population? Human population has grown from a few million 50,000 years ago to nearly 7 billion today. That’s a form of progress as well. Or what about the ability to utilize a greater proportion of the earth’s resources? There are few places on this earth, few species, few resources, that have not already been tapped by humanity, and we continue to expand our grip on the natural world. That’s a form of progress, too -- one that we’re not handling very wisely. Political and economic integration provide another form of progress: our political institutions keep growing in size, with fewer institutions handling a greater percentage of humanity’s political issues. Our economies grow ever more entwined. A hundred years ago, the average earthling had little idea of what his peer in a faraway country might wear, eat, or speak; nowadays, my home is full of doodads designed in some countries, manufactured in some other countries, using raw materials obtained from still other countries. I’d be willing to bet that, if we were to trace the components and materials of all the stuff in my house, and put a pin on the map for each place that each material had come from or was worked on, we’d end up with a map covered with pins everywhere. Our world is vastly more integrated than it has ever been, both economically and politically. That’s a kind of progress, too.
So there are many kinds of progress. But here’s the real kicker: they’re all tied together. It would be impossible to have progress in any single one of these areas without concomitant progress in all the others. Consider the list of forms of progress:
Political and economic integration
Can you imagine any alternate history of humanity in which any one of these areas of progress did NOT show any progress, while the others did? How, for example, could we continue to have population increase if it weren’t for the agricultural technologies that have vastly increased crop yields? Or how could we have technological progress without economic progress? Who’s going to pay for all that scientific research? Economic and political integration wouldn’t be pursued in a low-population world because it wouldn’t be valuable: when people are thinly spread on the ground, they don’t need to get along together as well as when they’re rubbing shoulders. And you certainly can’t have economic progress without technological progress: a big economy needs high-tech stuff like electricity and computers and airplanes and all sorts of other stuff. Can you imagine our society being as wealthy as it is without cars, electricity, or a chemical industry? No matter which pairing of areas of progress you look at, you get the same result: you can’t have progress in any of the fields unless you have progress in all of the fields.
Thus, in order to get to the level of technological progress represented by interstellar travel, you’d need concomitant progress in all those other areas, and that includes progress in political and economic integration. Sorry kids, but you can’t have Star Trek until you learn to play together nicely. All this nonsense about terrorism and crime and wars -- I’m sorry, but if you’re so politically backward that you can’t keep from killing each other, you’re never going to pull together well enough to achieve the kind of economic and technological progress necessary to shoot rockets to the stars. Achieving space travel demands a high level of technological and economic achievement, and you can’t achieve those levels without a concomitant high level of political achievement. Until you learn to dispense with those silly nationalisms and start thinking in terms of humanity as a whole rather than your stupid little countries, you’re not going anywhere -- which is a good thing. Who would want your kind traveling among the stars? You’d go around invading little planets, killing the locals, and acting just like the Monsters from Mars. If you’re eager to do that to your own kind, how compassionate will you be with truly alien people?
The converse of this is also true: the only aliens who could ever reach this planet are aliens who have attained a high level of technological, economic, and political achievement. They will have a single polity governing their entire population (what the radical right calls “world government”) and their economy will be well-integrated to permit maximum economic output so that they can spend the equivalent of quadrillions of dollars to build spaceships. So if they do get here, they’ll have more to fear from us than we from them. They would find themselves in the same position as a schoolmarm stranded among a bunch of bloodthirsty headhunters. My guess is that they would not want to have anything to do with barbarians like us. Perhaps they’ve already dropped by, looked us over, and posted signs all around the solar system:
But if they do decide to drop by and say hello, they will most assuredly put us to shame with their gentleness and good manners.
A less anthropocentric explanation
The previous explanation requires us to think about aliens as if they’re humans with latex masks. That’s pretty parochial, so now I’d like to present a broader, more intellectually rigorous analysis. I begin with a fundamental observation about life. Most people have difficulty defining life, worrying about things like self-replication (which anthropocentrically assumes death). There’s a better way to define life: a thermodynamic system that extracts negentropy from its environment and expresses that negentropy in its structure and behavior. This definition applies equally well to an individual cell, a human body, all of human civilization, and the entire biosphere. Indeed, it clearly exposes the idea that each of these levels of life is a way of pooling the negentropy accumulated by individuals of the lower level, thereby more efficiently utilizing that negentropy. A single photon intercepted by a chlorophyl molecule in a cell contributes negentropy to that cell. The cell is part of a blade of grass, and its negentropy contributes to the structure of the blade of grass. Then the blade is eaten by a bug, which assimilates the negentropy of that grass and uses it for its own purposes. The bug is eaten by a bird, which in turn is eaten by an eagle. The negentropy of that single photon is captured and utilized by the cell, grass, bug, bird, and eagle.
The source of all this activity is ultimately the sun, which bathes the earth in humongous quantities of negentropy. The entire biosphere captures only a tiny fraction of all the negentropy bestowed upon us by the sun. Over the eons, the biosphere has grown ever more efficient, increasing the fraction of negentropy that it reaps. How can we know this? Because so many species exist today that did not exist 100 million years ago, species that extract negentropy more efficiently. For example, flowers are a fairly recent innovation, only about 50 million years old. By utilizing the mobility of bees and other insects to spread their pollen, flowers are able to respond more quickly to changes in the environment and spread more quickly into previously uninhabitable environments. Grasses are another example: they are capable of flourishing in environments that are inhospitable to other kinds of flora. We -- the earth’s biosphere -- just keep getting better and better at reaping the bounty of negentropy bestowed upon us by the sun.
We can reasonably expect a similar set of principles to govern the development of life elsewhere in the universe. All that talk about water and correct temperature zone for life is a bunch of rubbish. The first and most basic component you need for life is lots of negentropy. The closer you are to the surface of a star, the more negentropy you get per square meter. However, in order to reap that negentropy, you need some kind of physical mechanism, and this is where water and hydrocarbons come into play. Yes, organic chemistry affords the kind of chemical complexity you need to build living systems, but we have no way of knowing that organic chemistry is the only route to physical complexity. Magnetohydrodynamics -- the interactions between magnetic fields and plasmas -- afford immense complexity, much to the frustration of physicists attempting to build fusion reactors. Semiconductors offer another avenue to complexity, as demonstrated by the electronics industry. Given enough time and enough negentropy, why couldn’t small rocks develop a complex set of interactions based on thermal expansion and contraction moving things around? We already know that the interaction of water, water vapor, and air is capable of generating weather, with tornados, hurricanes, lightning, thunderstorms, and even ball lightning. If some planet had these ingredients, plus some other chemical species that also interact with water, light, or heat, how do we know that it wouldn’t develop some meteorological form of life? For that matter, how do we know that the Great Red Spot on Jupiter isn’t alive in some sense?
So let’s set aside all this anthropocentric nonsense and think in larger thermodynamic terms. Any biosphere anywhere in the universe will be harvesting negentropy from a nearby star (although we can’t rule out the possibility of biospheres inside large bodies that support fusion reactions in their cores -- once again, Jupiter comes to mind). Somehow that biosphere must combine the negentropy from a large surface area. Photons exist at the atomic level, but to get enough photons to build really big stuff, a biosphere must have the means to harvest and concentrate negentropy from a large surface area. That’s the central problem. Here on earth we solve the problem with a combination of plants and animals. The plants move negentropy short distances through physical pipes, while animals concentrate the negentropy from a broader area by moving from plant to plant, eating them. However, there’s nothing absolute about this solution: a biosphere could be entirely floral, using pipes that concentrate nutrients over huge distances. It could achieve concentration by opportunistic nomadism, relying on ocean currents or aerial winds to move components around for it. Moreover, we needn’t rely on photons as a source of negentropy: right here on earth we have entire biomes utilizing the negentropy provided by geothermal heat. Why couldn’t a planet exist in which the supply of geothermal heat is ubiquitous enough to permit large-scale concentrations of negentropy? And for that matter, why must life directly rely on photons? It’s entirely possible for photons to interact with matter to produce more complex compounds, which themselves become a source of negentropy to feed a biosphere. This would permit a biosphere shielded from direct exposure to sunlight.
Thus, there are plenty of ways to harvest and concentrate negentropy; life in the universe is surely much more alien than Hollywood can imagine. But the central requirement of any biosphere remains the same: harvesting and concentrating negentropy over large areas. The whole idea of layers of organization such as exists on earth (cells, creatures, societies, humanity, biosphere) is only one way for organizing the harvesting of negentropy. Our concept of conflict, of “dog eat dog” (or, or that matter, “eagle eat bird that ate bug that ate plant”) is predicated on this concept of layers of organization. It is just as conceivable that a biosphere on another planet could consist of a single entity composed of multiple cooperating components. But if there were another biosphere with our kind of layered structure (implying individuals, implying conflict), that biosphere would face a huge challenge in concentrating the enormous quantities of negentropy required to mount a campaign of interstellar exploration. The challenge could only be met by very close integration of all the components of the system. In other words, all the parts of the system would have to work together with little friction to achieve such a result. Cooperation, not conflict, would be required. Indeed, conflict is destructive of negentropy, and so the progressive minimization of conflict would be a fundamental requirement of any such biosphere.
It seems to me logically inconsistent, then, to imagine a biosphere capable of interstellar travel that would be organized in such a manner as to include conflict in its structure. Internally, it would be a maximally cooperative system. The notion of conflict would be so far removed from its decision-making process that it simply would not be able to conceive of a conflicting relationship with anything else.
But that would make for a terribly boring movie, so don’t expect anything like it coming to DVD soon.