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Thesis
Thermodynamics is inescapable in its generality. In its purest form it has been seen by generations of intrepid scientists in the inanimate realm of chemistry and physics, but if we grasp its essence we see the concepts and the principles at work in our daily lives and they become clearer by standing out in the great confusion of human behavior.
The Argument
Thermodynamics is a key theory of chemistry, physics, and all natural sciences. This statement would generally be accepted as a fact. However, thermodynamics is a
little-loved part of the science curriculum. The theory is abstract, perhaps to the point of being forbidding to some,
and thought to be applicable only to inanimate matter.
Its claimed applicability to engines and refrigerators
appeals mainly to the technically oriented student. Its great
generality and power remains hidden by layers of abstraction
and axiomatic rigor. Must this be so? Could we not gain
much by loosening the strictures and bringing the main
point home by more qualitative applications of
thermodynamics to the widest range of everyday experiences? An
attempt, at the same time loose and seriously meant, follows. I
will argue that given the proper translation of terms and
concepts from the inanimate to the animate world the laws
of thermodynamics can be seen at work in our everyday
lives. No proofs will be offered and we should not be
surprised that human behavior will remain richer and more
complex than our simple analogy could possibly explain. Even
in their usual habitat the laws of thermodynamics were
never more than idealized limiting laws. In the animate
applications the ifs and buts will not be fewer but the telltale
signs of thermodynamic laws at work may be more
impressive. The work we do to recognize these laws so far from
their home may clarify their meaning also in their normal
applications and persuade us that such power and generality
is worth the effort to learn and use.
In order to illustrate the deepest roots of
thermodynamics and its great power and generality I shall apply
it to human behavior from an economic point of view.
Many economists and marketing executives would like to
know what drives human behavior in the so-called
marketplace. Thermodynamics explains what "drives" inanimate
behavior, that is, which processes will spontaneously occur
and towards what equilibrium conditions they strive. Thus
we might apply this theory also to economic behavior of
humans. In thermodynamics the two quantities of greatest
interest are the energy and the
entropy. Energy is a property of all physical systems that is conserved in total but
transferrable among subsystems. The availability of energy is
a precondition for states to occur. Thus the transfer of
energy is directly connected with the possibility that the
system change its state. Perhaps the first and simplest, but
imperfect, observation associated with thermodynamics is
that usually the surroundings seek to minimize the energy of
any given subsystem (the small part of the universe you are
focusing on). Thus energy minimization seems to be a
driving force of nature. Its effects are most clearly seen in
the preference of molecules for their lowest energy
electronic states, in the fact that stones tend to roll down hill and
rolling cars stop unless pushed on by an engine.
While the tendency of nature (the surroundings)
to minimize subsystem energy is readily accepted it
becomes less obvious upon further thought. In the form of heat,
energy often flows the other wayfrom the surroundings
to the subsystem. Apparently the spontaneous energy
redistribution observed in nature is related to a more
fundamental driving force. The initially more subtle but in the
longer term more obvious rule of thermodynamics is that
nature seeks to maximize the number of available
states. This rule applies also to the case of a closed system wherein all
states have the same energy. One can now understand that
the first rule, that energy is minimized, is a consequence of
the second rule, that the number of states is to be
maximized. The transfer of energy from the subsystem (i.e., the
energy minimization) makes energy available to the rest of the
system (the universe) so that it can increase the number
of states available to it. Let us call "the number of
available states" W. Then the entropy is defined as
entropy = S = kB ln W
where kB is the Boltzmann constant, a positive
constant, and ln denotes the natural logarithm. Since
S grows logarithmically (i.e., monotonically) with
W we can see that maximizing W is the same as maximizing
S. Thus we can state the fundamental rule of thermodynamics as
Nature seeks to maximize the entropy.
For a closed system that does not exchange energy
with its surroundings this rule alone determines whether a
process is spontaneous. Thus it applies also to the universe
as a whole. More commonly we consider a small subsystem
of fixed volume exchanging energy with its surroundings
acting as a thermal reservoir. The fundamental rule leads to
a corollary for this case:
Nature seeks to minimize the free energy
E TS
of a subsystem.
This result follows from the fact that entropy
increases with energy E for both the subsystem and its
surroundings. T is the inverse of the rate of increase of the entropy of
the reservoir with increasing energy. We call
T the temperature. It determines the direction of energy flow, that is, from
high towards low temperature. From the point of view of the
subsystem the energy minimization or the entropy
maximization may predominate depending on whether
T is high or low. From the point of view of the universe only the
entropy maximization applies.
Now we turn to human behavior. It is incredibly
complex so we shall have to be satisfied with gross
simplifications, but perhaps we can still grasp the essence of the
phenomena we wish to describe. I will now propose the
following identifications:
· energy = wealth
kinetic energy = cash
potential energy = property
· entropy = freedom
Will this mapping of thermodynamics onto human
behavior have any merit? Note that the tendency towards
energy minimization then corresponds to the observation
that the natural action of the environment on an individual
is to make him or her poor. This is believable and the
reason is that the other humans want themselves to become
rich, so they want to transfer money or value from you to
themselves. The entropy rule corresponds to the
fundamental rule of human behavior:
Humans seek to maximize their freedom.
An individual acts to maximize his or her own
personal freedom but against this tendency stands the same
driving force acting on the other humans in the society to
which the individual belongs. Thus we should understand the
desire of someone to be rich as a desire to become free
and the desire of a salesman to have his customers' money
as an attempt to optimize freedom somewhere else in
society. The richer among us are more free in the sense that
they can place their money in many different investments,
which can be changed with time. Ultimately, what we want to
buy with money is freedom. This word "freedom" is perhaps
hard to define precisely, let alone maximize, but I claim that it
is a fair translation of the concept of "entropy" from
thermodynamics of inanimate matter to thermodynamics of
human life. It is also a most positive concept almost
synonymous with life itself. Who could then doubt the need for a
concept of entropy or deny its claim to be central to the theory
of change be it inanimate or animate?
The thought that the dry and forbidding discipline
of thermodynamics could be applied to that most
theory-defying of all applications, human behavior, may be
staggering, and perhaps heresy to some. After all, the purity and
precision of thermodynamics has been maintained on
the strength of its validity only as a collection of limiting
laws for infinitely large systems undergoing infinitely
slow changes. However, the interest in thermodynamics has
always been based on the great relevance for finite real
systems undergoing changes that are fast on our everyday
time scale and slow only on the microscopic time scale of
atomic motion. Thus we are merely extending the beam of
insight from the lifeless behaviors of inanimate matter to the
vivid complexities of human behavior. In the final analysis
this far-reaching analogy rests on the fact that the basic
elements of the description of atoms, molecules, and
matter can be scaled up to the realm of living organisms
without changes other than in the complexity of the systems
and their behavior. In its most elementary form the
thermodynamical view of reality can be summarized as follows:
Reality is described by a set of states and various
forms of dynamics that cause changes of states. There is
a quantity called energy which is conserved in the
dynamics of an isolated part of reality and thereby
constrains the states available to the dynamics. All forms of
dynamics tend to explore all parts of reality.
Our animate analogy claims that reality can still
be described by a set of states even though the dynamics is
of indescribable complexity. It proposes that money is a
commodity invented by humans to play the role of kinetic
energy to allow the dynamics to more rapidly explore
reality
by trade. It recognizes that the ultimate driving force of
all human behavior is the search for greater freedom,
which simply means that we have within us an urge to
explore reality in all its dimensions, shapes, and forms. When
Sir Edmund Hillary was asked to explain why he had taken
all the trouble to climb Mount Everest he is purported to
have answered "Because it is there".
Exercises, Questions, and Points of Discussion
1. Discuss the human driving forces that
brought down the Berlin wall.
Comment: Was it not a search for freedom acting like
an osmotic pressure that brought down the wall?
2. Which physical property most directly influences
the relative importance of energy minimization and
entropy maximization in an inanimate physical
system? Can you think of an equivalent property applicable
to human behavior?
Comment: Temperature establishes the balance
between energy and entropy in inanimate
thermodynamics. Would "standard of living" similarly describe the
balance between wealth (or poverty) and freedom?
3. Discuss the political systems
dictatorship and democracy from the point of view of the proposed rules
of human behavior. Which system of government is
most in tune with animate thermodynamics? How
might the level of education in a society influence the
choice of system of government?
Comment: Is not democracy a form of government
in tune with the thermodynamics of animate
behavior? It generates freedom (entropy) by spreading
decision making among all people. Clearly, the
individual rights granted all citizens are also balanced
against restrictive laws with the general intent of
maximizing total freedom in society. Dictatorship, on the
other hand, attempts to put a straightjacket on freedom
by a combination of threats and promise of material
reward. This runs counter to the basic law of
"animate thermodynamics". A high level of education
simply speeds up the irresistible tendency to maximize
freedom by making people aware of more alternatives
and better equipped to explore them.
4. In many texts disorder is associated with high
entropy. Give a critical analysis of the relevance of
this analogy within first inanimate then animate
thermodynamics. Is it true that anarchy maximizes
freedom for individuals? How is the need for law and order
related to the population density in society? Is there
an inanimate analogy for this aspect of government
of humans?
Comments: Disorder is, at best, a very construed
synonym of freedom. When used in texts on thermodynamics it is surely clear to the authors that disorder in an ideal gas increases with the volume; but to
most uninitiated, disorder is a more qualitative concept.
A gas may then appear to be as disordered in a
small volume as in a large volume. In the animate
realm, youthful observers may think that anarchy is the
ultimate freedom but the older and wiser know that
the constraints of the law, personal discipline, and
morality actually increase freedom when summed over
all members of society. The closer contact we have
with the rest of humanity the more we need laws,
discipline and morality. In inanimate thermodynamics it
is known that the hard sphere fluid, the structure
of which is only determined by the principle of
maximal entropy, becomes ordered at high density.
5. Is it true that spontaneous processes observable to
us appear to be driven mainly by energy
minimization? Why might this be so?
Comment: Energy minimization appears to rule
when the observed subsystem is at a higher
temperature (has more energy per degree of freedom) than the
environment. Observable processes around us often arise when macroscopic objects have been given
large (superthermal) amounts of energy which are then
in time dissipated out to microscopic objects in the
environment. We can see the macroscopic but
generally not the microscopic degrees of freedom. We can
impart energy to a few objects of our own dimensions but
we cannot see the many atomic and molecular
motions that receive the energy lost from the few
macroscopic degrees of freedom by dissipation.
6. In inanimate thermodynamics energy is usually
conserved in the total system considered. However, in
the world of human behavior, wealth is created and
consumed by each individual to a varying extent.
Consider the implications of this difference. Does it
invalidate the analogy?
Comment: Clearly wealth is an immensely
multifaceted quantity that will be hard to fit into the mold
of inanimate energy. However, is this not a problem
more of practice than of principle? There would appear
to be many cases of, e.g., economic behavior of
humans where the practice of "thermodynamics" is
comparatively straightforward. In other cases the
implementation of thermodynamics may involve
unfathomable difficulty.
7. Is human behavior more complicated than the
behavior of inanimate matter? Consider this question
and give supporting arguments for your conclusion.
Comment: The intuitive answer is "yes", but try to
justify it by considering what factors make an
inanimate problem hard and apply the same criteria to the
animate problem.
8. Thermodynamics is often applied to the evolution
of life-forms on earth. Critics have opposed such
applications, arguing that thermodynamics only
becomes applicable when, for example, an animal dies.
Which side of this argument do you favor? Why?
Comment: The very definition of life in
distinction from lifeless existence seems capable of generating
interminable argument. Perhaps the scale is
continuous and divided into life and lifeless only
by personal predilection. Where on such a continuous scale would
thermodynamics cease to be relevant?
Epilogue
Here we leave our open-ended excursion into
animate thermodynamics and return to the most pressing need
at handto convey the edifice of thermodynamics to
present and future students. From our analogy above we should
be able to gain:
· an antidote for the boredom, confusion or lack of
interest many captive students of thermodynamics feel;
· a new word to associate with entropyfreedom;
· a clear and compelling illustration of the content
of the second law of thermodynamics.
The power of the limiting laws of thermodynamics
is not their splendid purity but their ability to remain
relevant in the confusion of reality. Students live in the confusion
of reality. The animate analogy is an attempt to find
them there and bring to them the benefits of the purity of
the limiting laws of thermodynamics.
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