From: Eva Durant <[EMAIL PROTECTED]>
>You ignored the point I tried to make;
>borroing expressions from physics such as
>entropy
>and using them willy-nilly to make
>an economic or social statement
>look as pseudoscientific as astrology
>is.
You are out of date Eva. I am not borrowing terms from physics. The laws of
thermodynamics are now part of the sustainability literature at all levels.
Here is clip from one a new book I just bought:
THE ENVIRONMENTAL CONSEQUENCES OF GROWTH
by Douglas Booth; Routledge, 1998
http://www.amazon.com/exec/obidos/ASIN/0415169917
[snip]
Economic circular flow and the environment
Anyone who has taken macroeconomics is familiar with circular flow analysis.
Households purchase commodities produced by businesses, the expenditures of
households become the revenues of businesses, and businesses use those
revenues to purchase productive services (labor, capital, and natural
resources) from households. The incomes of households in turn sustain
expenditures on purchases from businesses. In the opposite direction,
commodities and services flow from businesses to households and the factors
of production flow from households to businesses. Commodities and money flow
in an unending circle that never runs down, and, with continuous investment
in additional productive capacity, the flow can be ever expanding.
This perception of the macroeconomy is misleading because it ignores
scientific laws that place constraints on the flow of inputs into the
economic system from the natural environment (Daly 1991a: 195-210). The flow
of energy and matter through the economic system is in reality linear and
unidirectional, not circular. Energy and matter flow from the environment to
the economic system and waste matter and heat flow from the economic system
to the environment. The flow begins with the depletion of energy and
material resources and ends with the pollution of the environment with waste
matter and heat.
As Nicholas Georgescu-Roegen and Herman Daly have gone to great lengths
to demonstrate (Georgescu-Roegen 1971, 1973; Daly 1991 a), economists have
failed in the construction of their macroeconomic models to recognize that
the laws of thermodynamics dictate an absolute scarcity of energy and
matter. It is this absolute scarcity that in turn negates the macroeconomic
concept of circular flow.
The essence of the first law of thermodynamics is that energy and matter
can be neither created nor destroyed. In other words, the stock of matter is
fixed in availability, as is the maximum flow rate of energy. Thus there is
an absolute scarcity of both. If energy and matter could be infinitely
rearranged without loss, then this law would matter little for economic
activity. The disordering of matter created by consumption could simply be
compensated by the re-ordering of matter through production. Perpetual
circular flow at a constant or even growing rate would indeed be possible.
The problem is, whenever energy is used to re-order matter, something is
permanently lost. This is explained by the second law of thermodynamics.
The second law of thermodynamics basically says that when used to
perform work, energy is converted to a more dispersed, less useful form. To
put it another way, whenever energy is used, some of it is given off in the
form of waste heat. The entropy of energy increases. No energy-using process
is 100 percent efficient. Entropy is the amount of energy in a system that
is not available to do work in that system. An automobile burning petrol
converts energy in a concentrated form into motion and waste heat. The
automobile moves, but some of the energy is converted into waste heat
unavailable for work.
The flow of matter in production and consumption is also an entropic
process. Highly concentrated forms of matter are converted into useful
artifacts in production, and in consumption those artifacts are converted
into dispersed waste material. The energy of nature - sun, wind, rain,
oxidation - causes materials to break down and become more dispersed. A
house, for example, slowly deteriorates over time. The paint chips off, wood
rots, and the roof deteriorates. An increase in entropy is a decrease in
order. As the house deteriorates, its material contents become less ordered.
To reconcentrate all dispersed matter from a consumption process would
require an impossibly large amount of energy, rendering 100 percent
recycling an impossibility. Matter, like energy, is subject to entropy.
The extent to which the entropy of energy and matter impinges on the
circular flow of commodities in the macroeconomy or harms the human
individuals and natural environments that frame the macroeconomy is a
fundamental issue that must be addressed by an environmental approach to
macroeconomics. The entropic linear flow of energy and matter results in
changes to both biotic and abiotic components of what can be called the
global ecosystem. Abiotic components include the earth's atmosphere and
climatic patterns, the input of solar energy, and the reserves of energy and
materials in the earth's crust. The biotic components include a vast array
of species and biological communities created and shaped by the interaction
of natural evolutionary forces and ecological processes, some of which have
been further altered and reshaped by the human hand.
In short, the fundamental problem facing an environmental approach to
macroeconomics as an area of intellectual inquiry is this: the global
economy is growing while the global ecosystem is stable in terms of its
capacity to supply energy and materials, absorb wastes, and provide a host
of ecosystem services (Daly 1991 a: 180-194). As a result, stocks of
nonrenewable resources in the earth's crust are being depleted, waste sinks
are filling up, and human-created ecosystems (i.e. agriculture) are taking
over a larger and larger percentage of global biotic productivity. Further
consequences of these events include a plunge in global biotic diversity,
the disappearance of natural habitats (such as tropical rain forests) and
numerous environmental problems including global warming, air and water
pollution, toxic wastes, and destruction of the protective ozone layer. To
fully understand the impact of economic activity on ecosystems we need to
know something of the services they provide. Then we will be able to move
forward and consider the economy-environment relationship in detail.
