In an e-mail from a disgruntled reader:
Your argument seems to rely heavily on the physical definition of work, i.e. the displacement of mass over some distance and in some time allotment. Yet you continue to talk about this 'useful' work as if it somehow magically changes energy into money. What do you mean by useful work anyway? Isn't work, work?
As you know by now, I like good questions.
The reader is right. I owe everyone an explanation of what I mean by useful work so as to show the relationship with money more completely. As I hope to show, the concept of useful and that of utility, as used in economic theory, are definitely related. But there are also subtle differences, which I feel many economists have missed, and hence put too much reliance on the latter in explaining choices in economic decisions.
I'll start with a simple example. Suppose I take an electric fan and plug it into a long extension cord outside my house on a chilly day in December. I turn it on and it blows air. It is converting electrical energy (flow of charge) into mechanical (rotational) energy and through the shape of the blades into another form of mechanical (vertical acceleration of air molecules and pressure waves). The energy doing all of this is used up and transforms into heat that dissipates into the environment. The blown air's velocity dissipates similarly due to friction. In the end many bits of matter were moved, and hence we have to say that work was done and energy used. But so what?
Different scenario. Hot day, my TV room, fan blowing. It is cooling me off by the air helping to evaporate the moisture on my skin. The fan is doing work but now it seems somehow useful, at least to me. But there is a lot more to this story than just keeping cool one couch potato watching a movie.
Let me go back now to try and put some kind of definition on 'useful work'. If you recall I differentiate between manufacturing of tools as compared to manufacturing of excessive play things. Now I should make this differentiation clear and especially the nature of tools. A tool is any device, organization of devices, or procedure for performing work that increases the net useful energy in the future.
A tool can be used to:
- convert raw energy into useful energy
- increase the efficiency of energy use thereby increasing the overall supply of useful energy
- make another tool
You may have noticed a slight change if phrase with respect to energy. Now I'm talking about 'useful' energy. Previously I used the term 'free' energy to distinguish a form of energy that could do useful work. The term 'free' comes from physics and it means that amount of energy available from some high potential source which can be directed into a work process and move the pieces about to get the work done. Here, high potential means something like high concentration of raw energy. For example the Sun is a source of high potential light energy (electromagnetic radiation). But only a fraction of that potential can be used by plants in photosynthesis. The rest (except for some portion that is temporarily absorbed at the surface and then re-radiates at a lower frequency) simply reflects off the plant back into the sky.
Useful energy is that portion of a stream of raw energy that is in a form, and sufficiently powerful, that it can drive useful work. Whether or not it ends up doing so depends on a number of factors, but it all boils down to there being a work system (like the chloroplast in green plants) that can use that energy.
If this sound somewhat like circular reasoning to you — useful energy does useful work, but useful work potential creates useful energy — let me point out that it is actually more spiral thinking! That is, the flow of raw energy into a generally unorganized system will tend to drive internal processes of self-organization and the emergence of sub-systems better able to utilize the available energy. Harold Morowitz, the biophysicist, summed it up beautifully, "The flow of energy through a system acts to organize that system." His monograph, "Energy Flow in Biology", is a classic must-read for anyone who really wants to understand this. What Morowitz describes is what we computer scientists think of as a bootstrapping process. That is a very small piece of a system can generate a larger, better organized piece, which in turn generates an even better organized piece, and so on. Each new, more complicated piece is more powerful and better able to do work. Meaning that as time goes on, the overall system becomes better organized internally and can thus convert more raw energy into useful energy.
This figure somewhat captures this notion.
In the top panel we see a system that is internally disorganized, for the most part. It receives an input of raw, high-potential energy (from the left) and the energy mostly dissipates through the system, radiating out as low potential heat. Internally some small portion of the system, a sub-system, is able to use a small portion of the energy influx to do the work of organizing itself by capturing some additional components and incorporating them into a structure. In the second panel a more developed subsystem is able to capture more of the raw energy and continue the organization of more components. These panels do not show the fact that energy flows through the sub-system and radiates outward as heat, just as for the system as a whole. But that is the case, which is why the heat coming out of the whole system remains the same (essentially) in all three panels. In the bottom panel the system is largely organized, in this case into a few sub-systems that interact and sometimes route energy flows between them. This is what I have referred to in earlier posts as the currency in a system. Note that the first sub-system acts like a 'catalyst' in enabling other sub-systems to organize and develop. Morowitz was attempting to connect this kind of process with the origin of life and evolution. Evolution, of course, eventually produced human cleverness.
Useful thus means, in this context, anything that leads to greater organization and conversion of more raw energy to useful (free) energy. It is a self-reinforcing loop, a positive feedback loop, that will continue in that process until it reaches a point at which no more new useful energy can be obtained. The system will reach a steady-state, assuming the energy flow remains constant, an no new organization will emerge.
But back to the nature of tools. From the above argument it should be seen that a tool is any little piece of the system, in this case we are talking mostly about the human economic system, that represents this bootstrap organization. A plow makes it possible to produce greater yields per unit time. The greater production of food makes it possible to spend more time improving the plow. And so it continues to the present time. Our entire technology base is a complex set of tools, and hierarchies of tools, that deliver useful energy to each of us that are in a position to take advantage of it.
In a real sense, the whole of our cleverness (intelligence + creativity) is directed at enabling this spiral to continue to build. As long as there is raw energy flow to exploit, we will find some way to do so. Evolutionarily, human cleverness was selected for simply because there was more raw energy to exploit than what life had already managed. Taming fire, inventing spears and axes, taming animals for labor, planting seeds, and so on, all of it has been a steady increase in exploiting energy sources to increase the per capita energy directed at serving human ends. Today, machines using tremendous amounts of energy (not always efficiently) produce those things that humans seem to want.
Finally, by all of this you might be able to guess what I mean by useful work. Any work that creates or uses tools, thereby increasing the availability of useful energy is useful. Any work that dissipates energy without increasing availability of energy is waste. It will be that way until the last bit of useful energy can be extracted from the flow of raw energy and then the system will settle into the steady state. Producing products and services which purely dissipate energy without ultimately increasing the availability of useful energy is, in this sense, a sin! And this is why people who are becoming vaguely aware of this fact are looking upon excessive entertainments and over-the-top consumer goods (e.g. Humvees) disdainfully. Deep down inside, many people sense that these are wasteful. I hope this explanation helps understand why.
But the real problem is this. When humans discovered fossil fuels, they tapped into a storehouse of raw energy (fossil sunlight) that expanded almost instantly the size of the influx of high potential energy (imagine in the second panel above doubling the width of the in-flowing stream). All well and good. We increased our organization (civilization) and increased the availability of useful energy. This is exactly what nature programmed us to do. We may not have done it wisely, a major faux pas in evolutionary terms, but we did it exactly as we should given our limitations of foresight and insight.
The only problem is that this source was a finite one, non-renewable in today's jargon. And we ignored that obvious fact. Now the piper is asking for his pay. The bank is nearly bankrupt. Oil production is peaking and it will be followed soon after by coal and natural gas peaks. After that imagine the influx in the figure slowly but inexorably narrowing. What was made possible by having a constant flow of high grade energy will unravel. We will go from the bottom panel toward the top in a kind of reverse evolution - devolution. That is, unless we figure out how to stabilize our energy sources, supplementing the fossil fuels with real-time solar, tidal, geothermal, and nuclear (wind and hydroelectric are forms of solar).
Unless the general populace understands all of the above and sees, as per my proposal to make money = energy, we will not use our cleverness rapidly enough to prevent some, probably catastrophic, devolution from occurring. I hope, of course, they will understand.
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