My second novel should be out later this year–I have just finished final editing, so the book now moves into publication. To celebrate, I’m posting an excerpt from the essay on science at the back of the novel. The following is based largely on material I learned from Tom Wessels and Charles Curtin, either in class or in personal discussion–and yes, I thank them in the book.
Essay Excerpt 1: On Exoskeletons and Ox-carts
Ecological Memory depicts a world that includes both ox-carts and robotic exoskeletons. Some readers might ask why. Yes, this is a world without fossil fuel, but it is clearly a technologically advanced society, so why are the people stuck using ox-carts? Why not use renewable energy?
The short answer is that they can and do, but if they used enough renewable energy to replace fossil fuels fully they would just wreck the world again. Where energy comes from is generally less important than how much is used.
People are used to hearing, and telling, the story of technological progress in terms of innovation. Cars are more advanced than ox-carts because they go faster. The other—often forgotten—side of the story is energy. A car that ran on a few bales of hay could not go much faster than an ox, no matter how advanced it was. Advancing technology has allowed the use of more and more energy, and that—not innovation alone—is what gives us our unprecedented power.
Fossil fuel has made increasing energy consumption possible because it is energy dense, easily portable, and abundant (or, at least, used to be). Fossil fuel also causes climate change and ocean acidification; and it indirectly causes several other ills, such as loss of biodiversity. The mechanisms involved should be roughly familiar to most readers. The surprise is that drawing the same amount of energy from other sources would likely cause similar problems; only the mechanisms would be different. Understanding why requires exploring the science of complex systems.
“Complex”, here, has a specific, technical meaning: a system is complex if it has certain properties, such as self-organization and a nested or hierarchical structure (complex systems can have other complex systems inside them). I am a complex system, and so are you. So are cells, ecosystems, and entire biospheres. Books have been written about these systems, and they are worth a read, but the important thing to know is that systems science is all about the flow of energy. Complex systems can fight entropy and win. Readers may remember that entropy is the tendency for everything in the universe to run down as energy dissipates. Complex systems do lose energy to dissipation, but they do not run down, because they actively draw in energy from outside themselves. If a system is drawing in more energy than it loses, it is anti-entropic. Think of a baby, eating and eating, turning all those calories into growth and development, or a young forest, rapidly increasing in biomass and biodiversity. Eventually, the complex system reaches a point of equilibrium where energy inputs equal losses, and growth stops: that is maturity. From the standpoint of systems science, individual human beings remain mature only briefly. Almost as soon as people reach full size, our metabolisms slow and we start losing energy. We enter what is called the entropic phase. More colloquially, it is called aging, though injury or illness can trigger an entropic phase before maturity, too. A system that stays entropic long enough will cease being complex. That is death.
All complex systems go through these phases, though not all become entropic automatically with age. Forests never die of old age, but they can become entropic. A forest on fire, for example, is losing energy (in the form of heat and light) at a fantastic rate. If the fire is not too severe, the forest will survive and become anti-entropic again as it regrows. As Andy explains in the story, size, complexity, and stability increase and decrease together. A mature forest has more biomass and is more complex than either a young, recently-sprouted forest or the pile of ash and cinder left behind by a forest fire. Similarly, adult people are not just bigger than babies; they are also smarter and more resistant to disease. There is a reason people sometimes call the latter part of the human entropic phase a second childhood: bodies shrink, becoming less capable and less healthy as they lose energy.
All this energy must come from somewhere. Complex systems draw energy from the larger systems they are nested within. My cells draw energy from me. I draw energy from my society by working for a living and buying things. My society draws energy from the biosphere. The catch is that if the smaller system draws too much energy, it can force the larger system into an entropic phase. The larger system can even collapse—cease to exist—leaving the smaller system floating loose in whatever system the larger one was nested within. Think about why cancer kills if it is not successfully treated. Think about how unsustainable logging kills forests. Think about what follows from the rapid burning of fossil fuel.
The biosphere, too, is a complex system, and it, too, has had anti-entropic phases when it was actively growing, becoming more complex and more stable. The biosphere draws its energy (mostly) from the sun, through the process of photosynthesis, which gives us all our free oxygen and most of our biomass as well. And the carbon at the heart of that biomass remains part of the biosphere as long as it is part of chemical compounds that store energy captured by plants—which means that fossil fuels still count as biomass. When Earth was young, the growth of the biosphere, including the growth of its fossil fuel deposits, drew down the atmospheric carbon dioxide concentration. When the biosphere entered its mature phase, the carbon dioxide level more or less stabilized. Now that we’re burning fossil fuels, we’re liberating that stored energy and the CO2 concentration is rising rapidly as carbon leaves the biosphere—this loss of both biomass and energy means that the biosphere is now entropic.
Let me repeat that: Earth’s biosphere is currently entropic because of human activity.
Loss of stability, complexity, and size always accompany loss of mass and energy as a complex system starts to die. In human beings, that means poor health, increasing disability, and the wasting away of various tissues. Erratic weather, changing climate, and loss of biodiversity are simply the same pattern applied to the biosphere as a whole.
That burning fossil fuel should trigger a global entropic phase should not be surprising, given that the whole point of fossil fuel use is to access a lot of energy, quickly. Earth receives a certain limited amount of solar energy every year, and plant and animal life, as well as the movement of wind and water, takes place within that energy budget. If the human species confined itself to the same annual budget, living on sustainable forestry, agriculture, and renewable energy sources, most of the consumption that people take for granted today would simply be out of reach. Fossil fuel makes the more we want possible, and does so by delivering energy at a higher rate than the biosphere receives. Biospheric entropy is the inevitable result.
If the human species stops using so much energy, the biosphere will re-enter an anti-entropic phase and recover—though it will take a very long time for full recovery, possibly millions of years. That’s better than not recovering at all, and the sooner we reach carbon neutrality, the more likely we are to have a livable planet during the recovery period. Hope remains, though time is getting short.
Giving up fossil fuel entirely is probably a necessary step towards sustainability. What is the alternative, some complicated global carbon rationing system? Who would administer or enforce it? And why would anyone bother? Truly sustainable fossil fuel use would—by definition—yield no more energy than renewables can.
But the end of the Age of Fossil Fuel alone will not rescue us. Should we ever find and use an alternative way to draw more energy than the biosphere has to spare, the system will be back in the same entropic muddle it’s in now. Imagine replacing a Stage Four cancerous tumor with a six-mile-long tapeworm. The patient still dies; the only difference is the mechanism.
Energy is energy. Using too much has consequences.
One way or another, human over-use of resources will end. Unsustainable processes do end, by definition. We can survive only by shifting to an energy budget similar to what existed prior to the Industrial Revolution—a change that will impose real limitations on what the species can do and how it can do it. But a return to pre-Industrial limitations need not mean a return to pre-Industrial life.
An energy budget is not a time machine. There is no mechanism by which limitation alone can erase scientific and cultural advances or prevent further advances. Where those new advances might lead, I cannot say. I have simply imagined one possibility—one that includes both exoskeletons and ox-carts.