The Second Law of Thermodynamics is the Final Cause of Reality
Why We are Here
It is often said that the existential question “why are we here?” is beyond the reach of science.
I disagree: science has already answered that question.
The question can of course be approached in many ways, depending on one’s metaphysical or religious predilection. In another hub I advocated the existentialist (or humanist) position that human beings are here for whatever purpose they choose. For many of us, the best choices are motivated by love and justified by reason. But for those of a religious bent such humanism does not suffice, so external authorization is sought (the legacy, in my view, of the bicameral mind of our ancestors). But neither of these positions really addresses the ultimate question: why, of all things, did the universe happen to produce human beings?
The science-based answer I present here is neutral in regard to the existence or non-existence of God. If God exists, then the answer gives us deep insight into his or her mind. If God does not exist, the answer stands on its own. So for present purposes we can dispense with the God concept; it is superfluous.
The answer to the question “why are we here?” can be deduced from first principles, which I take to be the laws of thermodynamics. My reasoning is as follows: anything that happens (i.e., any kind of real change, including that which led to our being here) happens because of the flow of energy—or said another way, change entails the movement of heat, i.e. thermodynamics. It is thus governed by two laws. The first law states that energy cannot be created or destroyed (“nothing comes from nothing”). The second states that whenever something happens, some of the energy that went into making that thing happen is lost to heat—that is, it is converted from a form that can be used to perform work (‘exergy’) into a form that cannot (‘entropy’). The irreversibility of time manifests this second law. So do many other well known, everyday phenomena, like diffusion, melting ice, the eventual breakdown of vehicles and appliances, death and aging (some biologists will disagree with this last example, based on a fallacious argument about life being inherently regenerative; but I will leave that story for another hub...).
As I stated in my series of hubs on the nature of change, I prefer to think of the second law of thermodynamics as the One Law, because like Sauron’s “One ring” (from Tolkien’s Lord of the Rings), it can be said “to rule them all.” Ultimately anything that happens does so as a result of dissipation. In other words: shit happens in order to dissipate energy gradients.
You can probably see where I’m going. But to get there we need to extend the One Law with a corollary. And that is this: whenever an energy gradient is dissipated (as must eventually happen, according the One Law), it is dissipated as fast as possible given existing constraints. Rod Swenson, a theorist who developed this idea, refers to it as the Law of Maximum Entropy Production; more commonly it is known as the Maximum Entropy Production (MEP) principle. The idea is simple and quite intuitive: Swenson illustrates it by having us imagine a cabin on a cold snowy mountain. The cabin is heated by a woodstove that has just run out of fuel. Over time the heat within the cabin will dissipate into the surrounding air. By the MEP principle, this will happen as fast as possible given existing constraints. Thus, it will happen more quickly if doors or windows of the cabin are opened (removing constraints) than if they remain closed.
Swenson states his Law of Maximum Entropy Production as follows:
A system will select the path or assemblage of paths out of available paths that minimizes the potential or maximizes the entropy at the fastest rate given the constraints.
I am going to argue that this principle holds the key to understanding the origin, development, and evolution of human beings, life itself, and the universe as a whole. In short, the MEP principle answers the question “why are we here?” with: “in order to maximize the rate of entropy production”. If you look around you, I think you will be hard pressed to find any evidence that refutes this. But I am getting ahead of myself.
A major sticking point in discussions of thermodynamics is the mistaken notion that the second law only produces disorder. This notion, an oversimplification of the statistical mechanics developed by Ludwig Boltzmann (1844-1906) to interpret the second law, is often used by intelligent design sophists to argue that the natural origin of life is extremely improbable (if not impossible), because life is highly organized and hence 'goes against' the second law. The usual counterargument (based on the same misunderstanding of thermodynamics) is that the second law only applies to closed or isolated systems that are near thermodynamic equilibrium, and hence does not prevent the spontaneous origin life. This is all nonsense. The second law—the One Law—applies to everything and all systems, be they open, closed, near to, or far from equilibrium. While the One Law does indeed entail the progressive disordering of systems that are near equilibrium, it often entails the opposite in natural systems that are far from equilibrium, as shown by the Nobel Prize-winning chemist Ilya Prigogine (1917-2003). We can observe many self-ordering processes that manifest the One Law—for example, the formation of ice and other crystals, or vortices such as hurricanes and tornadoes. These phenomena all produce local increases in order, in the service of dissipation and with a global increase in entropy.
Moreover, they do so as fast as possible given existing constraints.
Do you see where I’m going? No? Read on...
Let’s back up a bit and consider what goes into the creation and dissipation of energy gradients. In the thought experiment of the mountainside cabin, the gradient was created through work—the building of the cabin, the cutting of wood for the stove, and the work done by the trees to produce that wood (as well as that contained in the structure of the cabin). All of this work was accomplished by dissipating various energy gradients (including that between the hot sun and the much cooler earth, which sustains most life on the planet). After the fire in the cabin expires, the rate at which the thermal gradient dissipates depends on how many openings exist in the cabin, as well as its insulation, etc.—that is, the gradient will dissipate as fast as possible given the existing constraints present in the cabin’s structure.
Consider what will happen if the cabin is abandoned. Because of the One Law it will gradually deteriorate over time, a victim of the many irreversible ‘forces of nature’—wind, rain, infestations—all of which serve to dissipate energy gradients. Now say a wayfarer happens upon the cabin after many years of such neglect, and uses it for winter shelter. He builds a fire in the stove, then goes to sleep, allowing the fire to die out. I think you will see that it won’t take long for the chill to set in—the heat dissipates much faster than it did before the cabin fell into disrepair. The reason is that holes in the structure have removed constraints, in the service of a larger world of dissipation.
So, not only does dissipation occur as fast as possible given existing constraints, but wherever and whenever possible, it works to remove whatever constraints happen to exist in a given locale. Toward that end dissipation drives creation as well as destruction, usually at the same time, one coupled to the other—whatever works to bring about the fastest possible production of entropy. Since entropy is always produced as fast as possible given constraints, and since the randomizing effect of the One Law eventually removes constraints, the rate of entropy production is bound to increase. Life is inevitable, because it allows a faster rate of entropy production than is otherwise possible. And the same is true of intelligence, culture, and technology.
Which brings us to why we are here: from the foregoing, you may have guessed that our purpose, in the bigger picture, is to dissipate energy gradients and maximize the production of entropy. And it is quite obvious that we are doing a damn fine job of it. Without us, all that rich energy buried in the earth’s crust would remain there, undissipated. The One Law prohibits that sort of thing form going on indefinitely. So the universe produced us to take care of it.
And there you have it: science’s answer to the ultimate existential question. We are here to serve the One Law. This is not to say that we can’t choose how we serve it—which brings us back to love, reason, existentialism, secular humanism, paganism, religion, whatever. But serve we must. Those who don’t serve don’t survive. Natural Selection—Darwin’s Preservation of Favoured Races in the Struggle for Life—is the executioner of the One Law. We struggle for life because we are part of nature’s dissipation project. And those who do the most effective job of dissipating are, for a time, nature’s “favoured races”—until someone else comes along that does a better job, or the gradient is completely dissipated.
So the next time someone asks you “why are we here?” tell them that it is because prehistoric life was buried beneath the ground and transformed into coal and oil, creating yet another energy gradient that needed to be dissipated as fast as possible. That particular job required brains and technology: so here we are.
I apologize if this sounds horribly nihilistic. But it is an inescapable conclusion of science, one that for emotional reasons I myself have resisted for many years. But to no avail: like death, there’s no getting around it. It explains everything. To quote Roger Waters: “What God wants, God gets...God help us all.”