当前，消费被奉为医治全球金融危机的万灵药。其实，这只是一个病态的解决方案，是目光短浅的经济学家膝跳反射般的本能反应。政治家们很快将明白，消费现有的意味着一点不剩。这就像救生船内的物资，因为我们所生活的地球就是一艘救生船（经济学家并不了解这一点，但聪明的人应该知道）。难道经济学家或政策顾问就无法理解吗——我们就是在一艘完全孤立、资源有限的宇宙飞船上，这艘飞船在真空中疾驰和飞转。就物质资源而言，我的‘‘收获’’就是你的‘‘损失’’。

吃豆者的寓意

我们不应该责备那些生活在两个世纪前的聪明人，他们的驱动政策是建立在无限“新大陆”的构想下。然而，1966年，阿波罗运载火箭上的摄像机镜头捕捉到了我们整个地球生存空间，今天，我们就不能再将我们的思维局限于人类的可持续性问题。我们应该重新反思我们目前的处境。

吃豆者（Pakman）可以看作是一个消费者的缩影，吃豆者是美国上世纪60年代住宅区附近商店柜台屏幕上最早出现的计算机游戏之一。吃豆者只是个漫画形象，圆圈之中有个三角形的嘴巴，他的目标是尽快吃掉在他面前的东西，而且越多越好，即它是个‘‘终极”消费者。这幕情景中有一个问题摆在我们面前：无论前方出现什么东西，消费都是免费的，且越快越好，此外，吃豆者还不会排放废弃物，即无固体废弃物、废水或废气产生。但是今天，如果决策者提倡消费作为解决问题的方法，那么明天的资源将不再免费，这样废弃物就成为亟待解决的问题。

吃豆者的‘‘世界’’是个令人气馁的科学模型。你和我都是吃豆者，各占据了仅0.07立方米的空间。与原始人一样，我们平均每秒吸入1.5升空气，每天饮用3升水，吃下半公斤粮食。没有氧气，我们几分钟就死去，没有水，我们几天内死亡，没有碳水化合物（C_xH_2xO_x），我们也活不了多久。但是，对原始人而言，世界似乎是无限的。尽管没有氧原子、氢原子或者碳原子的再生或被毁灭，不断到来的太阳光子驱动了碳和降雨的自然循环，从而补充了必需的资源。大自然循环利用了小部分的废弃物，甚至一些利用过的水和排泄物也在大自然的“下意识”似的安排中得到了循环再利用。

工业的吃豆者是另一回事。除去人类基本的需求，推动GDP的工艺进程除以全球67亿人口的结果是不可持续的消费和令人恐惧的“三废”的排放。工业吃豆者在平均80米宽、280米长的面积上运动，幸运的是，吃豆者有另外的资源，那就是维持生命必不可少的正常温度和大气调节“设施”——海洋，那么，对我们67亿人中的每个人而言，就是生活在平均280米长、200米宽（和3500米高）的空间中。每一个吃豆者都占据了7.6亿立方米的空间，这看似庞大，可是我们不必为此感激涕零。我们很难想象这个空间的大小，但是，正如我们跨入了2010年，资源和生态服务的现实情况也出现了一幅崭新的景象。这幅景象将加速决策者寻求新技术、甚至新范式的步伐，无疑地，我们不会听从老一辈经济学家采用加速盲目消费来推动增长的建议。

这个星球上的每个人大略使用1040米直径的球体的空气量，在这个低于2米的空间中，吃豆者看起来就无关紧要了。这无疑就是原始吃豆者的情况，并且，那时废弃物是不值得考虑的。对工业吃豆者而言，以今天的消费速度，如果平均每人按一生70年的消费，再把人一生的废弃物都保存起来，这些消费和废弃物对我们有限的自然环境造成了难以承受的负担。下表给出了近似数据。

下表列出了我们所需要的最基本资源，估算了1个人寿命70岁以吨计的消费量和排放量。

概念的转变

尽管经济学家从未考虑过这个问题，但重要的是我们要承认，物质消费与废弃物总量大体是相等的。理解问题严重性的困惑在于，在历史上，物质从未被理解为化合物，或者叫污染排放的化合物，人们甚至从未意识到这些。经济学奠基人大卫·李嘉图1817年在巨著中论述并断言，因为水资源丰富充足，所以水是“免费”的。甚至现在，政府在评估水资源价值时仍然有困难：有时候水是纯粹的降水或汇入了山间溪流，有时候水却是灾难性的泥水混合的洪水，而经过农场、工厂和家庭使用后，水通常又成为了污染物。20年前西方有句谚语，“随烟化为泡影”，意思是某件事物消失且变得不重要。现在，某些政府愿意为这种“烟”（即二氧化碳）开价每吨20美元，而一些企业声称他们将以每吨70美元价格买来贮存起来或者以某种方式安全处置。

设法合计土地、海洋和空气，无论是以吨计还是以立方米计，都让人左右为难；而市场尝试使用单位供给和需求的交点所决定的价格来解决这个难题。这是目前我们所拥有的最佳有效系统，同时，政府尝试以用公共资源（如水资源、公共用地）的影子定价和处罚排污者来管制经济活动。

但是，别让科学吓倒了我们。一个微不足道的1.65米（平均值）高的吃豆者其实只是一名演员，他像是一个直立的好事者，但他并不是“生物圈”的主宰者，尽管现在他有能力弄点破坏。如果一个人一生所产生的二氧化碳（全球290亿吨/67亿人口×70年），为302吨，变成固态干冰就是差不多边长7米的立方体。我们可以把它埋到沙漠。但是，事实上人排放的二氧化碳散开后组成空气体积的百万分之383。这不会引起中毒但也看不见。而推崇温室理论的科学家们足够大胆地预测，被地球表面反射的光子增加滞留后，将让全球平均气温升高若干度。在哥本哈根气候变化大会上，一个小岛国代表说道：当1.5摄氏度上限的升温被驳回，而采用了2摄氏度的上限时，他哭了。

《熵定律和经济过程》

1971年，哈佛大学印书馆印发了一本具有里程碑意义的著作《熵定律和经济过程》。作者尼古拉斯·乔治斯库-洛根（Nicholas Georgescu-Roegen），是一名经济学家，他花费数十年的时间在他的学科领域取得了相当重要的成就。他主张攻击传统观念，富于创新：他评判两个世纪以前在牛顿力学模型基础上建立起来的经济学——带着神奇发条的永动机是不可能的。他提醒人们，经济过程是单向流动的。1824年，卡诺（Carnot）研究蒸汽机时发现熵现象，1876年吉布斯（Gibbs）重新改进，并总结认为所有的化学过程中熵也都在进行。像热力学第二定律所囊括的那样，熵总是在增加中。幸运的是，在有限的物质环境中，太阳是一个外来源，能补充能量，维持我们的生命活动。

乔治斯库-洛根（Georgescu-Roegen）的书冲击了70年代，随之而来的是环境问题“苏醒”年代（如《寂静的春天》，《增长的极限》和石油危机），于是他受邀走向了世界各地。社会活动家杰里米·里夫金（Jeremy Rifkin）撰写了后续解释性书卷，阿尔·戈尔（Al Gore）为之做了篇序。但那之后，推动力消逝了。主要有以下四点原因：首先，熵是一个难懂的概念，甚至对热力学学生以及用它解决具体实际问题的化学家都如此感觉。当然，熵科学已经超越了如乔治斯库-洛根（Georgescu-Roegen）等老一辈经济学家的眼界。其次，直觉上它一如既往地令人兴奋，但在信息理论、艺术和伪科学领域没有容它之处，在伪科学中它被盗用和贬低。第三，长期看，经济学家所称颂的“市场可以调节”是正确的，在没有熵科学前，消费者最终发现能源低效和污染能够如此的“昂贵”，于是生产过程是被调节了，但却需要花费十年之久。最后，熵对商业和政治而言是一项不利的讯息。吉米·卡特（Jimmy Carter）在1980年讲演经济过程的谦卑时输给了罗纳德·里根（Ronald Regan）。经济学圣经——保罗·萨缪尔森（Paul Samuelson）的《经济学》，就以“Economics”为标题，在1980年第11版专门有一页论述熵经济学，之后就被抛弃，直到目前，第19版才重新出现。

但是，以旧科学为基础的旧经济学需要根据新科学进行更新。热力学第一定律以物质和能量不能被创造和毁灭作为出发点。在我们的地球上，对吃豆者而言，没有任何的原子被创造或毁灭（核工业是个例外）。我们并不生产碳原子、铁原子或氧原子。吃豆者在其有限空间内狼吞虎咽的“进食”并排泄“废物”。在重量上二者完全相等。这就是我们以后所需要的模型。

熵总是增加的，输入只来自太阳，并以一个固定速率补充这个循环。当然，我们碳的生产量远远超过光合作用所能固定的碳，而这正是我们必须理智解决的问题。图1是这个探讨的示意图。

by John E Coulter, translated by Wang Zhuoni

Consumption is now vaunted as the panacea to the Global Financial Crisis.  This is a sick solution and a knee jerk reaction by economists who do not see the big picture.  Hopefully statesmen will see that quickly consuming what you have leaves you with nothing.  Like the provisions in a life boat, because (economist do not know this but intelligent people should) the globe we live on is a life boat.  Don’t economists/policy advisors get it?  We are on a totally isolated, finite, spaceship hurtling and spinning through the vacuum of space.  In terms of material resources, my gain is your loss.

We cannot blame those clever people of two centuries ago who drove policy with a boundless New World vision.  But in 1966 our entire global living space was captured in a camera lens frame from an Apollo rocket and now we can no longer be small minded about our sustainability.  Let us rethink where we are at.

The epitome of a consumer is Pakman, the little bean eater in one of the first computer games appearing as a screen on a table in corner stores in the US in the sixties.  Pakman was just a caricature – a circle with a triangular mouth whose aim was to gobble whatever was in front of him.  The more the better.  The ultimate consumer.  There is just one issue with this scenario, now comes to the fore:  No matter what is out in front for the free taking, the faster the better, Pakman consumes but has no emissions – solid, liquid or gas.  If policymakers are advocating consumption as the solution to today’s problem, tomorrow’s resources will not be free, but the seriously under-addressed problem is waste.  The throughput, equal in mass defined by number of atoms, comes out the backside.  Policymakers need to be responsible for where waste goes.

A Pakman world is a daunting science model.  You and me, as represented by Pakman, occupy a mere 0.07 cubic meters of space.  As primitives, on average we inhale air at 1.5 liters/ second, drink 3 liters water and eat half a kilogram of grain a day.  Without O₂, we die in a few minutes, without H₂O we die in a few days, and without carbohydrate (C_xH_2xO_x) we can’t live long either.  But for a primitive person, the world seems boundless.  Even though not one atom of oxygen, hydrogen or carbon is created anew, or destroyed, the natural cycles of carbon and rain, driven by incoming photons from the sun, replenish resources needed. The small amount of waste is recycled by nature, and even some used water and excreta recycled by conscious design.

Industrial Pakman is another matter.  Apart from basic human needs, the processes driving GDP divided by global population of 6.7 billion results is unsustainable consumption and horrific throughput of waste solids, liquids and gases.  Industrial Pakman operates on an average surface that is 80 meters wide and 280 meters long, and fortunately Pakman has another resource which is a vital natural temperature and air conditioning service – the sea, and for each of 6.7 billion of us, that averages 280 meters long and 200 meters wide (and 3,500 meters deep).  Each Pakman has an airspace of 760 million cubic meters, which seems so enormous we don’t need to appreciate the fact. It is hard for us to imagine the scale, but as we enter the year 2010, a realistic inventory of resources and the ecological services brings a new view.  A view that should hasten policy makers to look for new technologies, even new paradigms, and certainly not listen to relic economists advising extrapolation of growth by accelerated blind consumption.

A sphere of air averaged for each person on the planet would have a diameter of 1040 meters, and depicting Pakman in it at under 2 meters height makes him seem insignificant.  This was certainly the case for Primitive Pakman, and waste was inconsequential.  For Industrial Pakman, consumption over a life of 70 years and back-up of waste over that lifespan, at today’s rates, can be seen to be putting unbearable burdens on our finite surroundings. Table 1 sets out approximate data

		INPUT	OUTPUT
oxygen	O2	1,004	795
water	H2O	642	792
carbohydrate	CxH2xOx	19	15
carbon dioxide	CO2	9	303
fossil fuel	CxHy	240	10
Totals	material balance	1,915	1,915

Table 1 lists the most basic resources we need and estimates the amount in tonnes an individual consumes and emits during a 70 year lifetime.

It is important to admit, though economists never dream of this, that in material terms, physical consumption balances with aggregate waste.  A confusing factor in attempting to comprehend the seriousness of the problem is that historically the substances were not understood as chemical compounds, or in the case of oxygen and pollutant emissions, not even appreciated at all.  Founding economist, David Ricardo, in his 1817 defining tome on resources, pronounced water as “free” because of its abundance.  Even now, governments have trouble valuing water, when sometimes it is pure falling rain or flowing mountain streams, sometimes as disastrous muddy floods, and after farms, factories and households have run it through their systems, often as pollutant. The saying, until two decades ago in the West, “Gone up in smoke,” meant for something to disappear and be of no account.  Now some governments are willing to value that smoke (as carbon dioxide) at $20/tonne, and entrepreneurs are saying they will buy it for storage or some form of safe disposal at $70/tonne.

Trying to aggregate land, sea and air as the three basic phases in physics – solid, liquid and gas in either tonnes or cubic meters is a dilemma that markets try to solve by fixing prices at the intersection of demand and supply curves in whatever units of measure.  This is the best working system we now have, and governments attempt to regulate economic activities by shadow pricing public resources like water and common land, and attempting to penalize polluters.

But let not the science daunt us.  A puny 1.65 meter (average) Pakman is an actor. almost a bystanding interloper, not a master of his biosphere, though now with capability to make a mess of it.  If all the carbon dioxide a person produced in a lifetime (global 29 billion tonnes / population 6.7 billion people x 70 years) – the 302 tonnes of it – were solid dry ice, it would be a cube of sides about 7 meters. We could bury in some desert.  But the emission is a gas, dispersing now to make up 383 parts per million of the volume of the air.  That is not poisonous, and it is invisible.  The scientists promoting Green House theory are bold enough to predict that the increased entrapment of earth surface reflected photons will raise global average temperature by a few degrees, and at the Copenhagen Climate Change Conference one small island representative said he had cried when a ceiling of 1.5 degrees Celsius increase was dismissed for wording that capped at 2 degrees.

I don’t think we can engineer the weather that finely.  But when Pakman gobbles 1900 tonnes of matter and then expels it as waste, that adds up to polluting the environment seriously, and we cannot foretell the consequences.  Climate may well warm, but we really cant foretell the factors at play.  Pollution has many obvious downsides, and pollution close to us is more obvious than that flowing away.

In 1971 Havard University Press published a book of momentous importance.  The Entropy Law and the Economic Process.  The author, Nicholas Georgescu-Roegen, was an economist of decades of respectable contributions to his discipline.  What he advocated was iconoclastic and revolutionary:  He criticized 2 centuries of economics as founded on Newtonian mechanical models – a perpetual motion machine of magical clockwork that was impossible, even in theory.  He reminded that economic processes are unidirectional flows: breathing, refining iron ore into iron, making cars… The phenomenon of entropy, discovered in 1824 by Carnot studying steam engines, and refined in 1876 by Gibbs to include all chemical processes is at work.  Encapsuled in the Second Law of Thermodynamics, entropy always increases.  Fortunately for us, in finite material environment, the sun is an outside source which can replenish energy, and sustain our life-giving flows.

Georgescu-Roegen’s book took the seventies world by storm, coming at a time of environmental awakening (understandings from Silent Spring, Limits of Growth, and the oil crises) and he was feted around continents.  A follow-up explaining volume by activist Jeremy Rifkin had a foreword by Al Gore.  But then the impetus died. Four reasons.  Firstly, entropy is a difficult concept even for students of thermodynamics and chemists who have to use it as an application is solving some specific practical problems.  The building blocks of its science will need to be taken down and restructured, probably needing quantum mechanics, to be of wider use.  Certainly its science was beyond the ken of an old economist like Georgescu-Roegen.  Secondly, as intuitively exciting as it was, it had no practical fit in the fields of information theory, art and the pseudosciences where it was usurped, and debased. Thirdly, the economist chant of “Markets will adjust” is true in the long run, and without entropy science, consumers eventually find out how expensive energy inefficiency and polluting can be, and production processes are adjusted, even if it takes ten years.  Finally, entropy was bad news for business and politics.  Jimmy Carter lost to Ronald Regan in 1980 preaching humility of economic processes.  The bible of economics, titled simply Economics, by Paul Samuelson carried a page on entropy economics in the 1980 eleventh edition, then dropped it up till now in the current nineteenth edition.

But the old crotchety iconoclast was right.  Old economic based on old science needs to be revamped on new science.  Consider this.  The First Law of Thermodynamics sets out that matter and energy cannot be created and destroyed.  So to talk of producing and consuming energy is unscientific.  Joule introduced the concept of energy and it actually conceals what goes on when chemical electromagnetic forces (in fuel) are converted to heat/work.  Though the equation works, it is non reversible, and therein lies its value.   (Horsepower is not the equivalent of horse manure)  The scientific approach is to track exergy conversion to entropy.  On our Earth, for Pakman, not one atom of anything is created or destroyed (except in nuclear industry). We do not produce one atom of carbon, iron, or oxygen.  They are all parts of magnificent (dare I say supernatural) cycles.

So Pakman is in his confined sphere, gobbling goods and excreting bads. In exactly equal tonnages.  That is the model we need from now on. Entropy always increases, and only the inputs from the sun, at a fixed rate, can replenish the cycle.  Of course our throughput of carbon far exceeds the photosynthesis that refixes carbon, and is a problem we need to sensibly address.  Figure 1 is a start for this approach.