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Re: Ecological Economics and Entropy



Jay Hanson <jhanson@ilhawaii.net> wrote for all to see:

>Harold Brashears wrote:
> 
>> If I may interject a moment, this fallacy is a weakness of people who
>> have no understanding of thermodynamics.  The concept of entropy
>> (disorder) constantly increasing applies only to a closed system.  If
>> you do not live in a coal mine, you realize that the earth is not a
>> closed system.  It receives a constant energy input from the sun,
>> energy which feeds evolution and life on earth.
>
>Harold,
>If you would have read a book in the last 50 years
> (or even checked my references), you would know better.

I read what you had posted, and this confirmed my belief that you do
not understand entropy.  Entropy is a condition or state of a system,
which can be used as measure of the disorder.  

In a closed system, entropy can never decrease, but, the earth is not
a closed system.  I am sorry you do not understand this, but in
practice, it means it cannot be applied blindly to a system, like the
earth, which is constantly receiving energy from the outside (the
sun).

>Economists in Europe have been reading about entropy
> and how it relates to the economy for years.
>  See:  http://csf.Colorado.EDU/authors/hanson/page17.htm
>
>
>Here a explanation of how thermodynamics is used in
> ecological economics:
>------------
>All matter and energy in the universe are subject to
>the Laws of Thermodynamics. In the discipline of Ecological
>Economics, systems are delimited so that they are meaningful
>to our economy. What does thermodynamics have to do with the
>sustainability of food production?
>
>The two essential forms of stored thermodynamic potential
>are "energy" (e.g., a barrel of oil) and "order" (e.g., clean
>drinking water and deep topsoil). "Entropy" is a measure of
>the unavailability of energy: the entropy of oil increases as
>it burns, and the entropy of a water table increases as it
>falls because more energy will be required to pump it to the
>surface. Entropy can also be thought of as a measure of disorder
>in a system: polluted water that requires purification has
>higher entropy than the same water unpolluted, and the entropy
>of topsoil increases when it is dispersed or polluted by salt
>from evaporating irrigation water.

Here, you have assumed that the earth is a closed system.  For
example, dirty water can be cleaned by the expenditure of energy in a
distillation process.  Energy ultimately derived from the sun.

I remember a relative (by marriage) of mine who was a creationist.
She maintained an argument essentially the same as yours, that
creatures could not evolve from less complicated (more disorder) to
states of more complication (less disorder), since this violated the
2nd law which, forbade a decrease in entropy.

She was correct, but only if she was speaking of a closed system.  She
was wrong, as are you, since neither of you have considered the
constant input of energy from the sun.

I do not intend to speak to you about this any further, as I consider
you to be as biased in your way as she in hers.

Regards, Harold
----
"The great dialectic in our time is not, as anciently and by 
some still supposed, between capital and labor; it is between
economic enterprise and the state."
	---John Kenneth Galbraith, A History of Economics,
            ch. 21(1987).


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