“Our Common Future” report b WCED:http://www.un-documents.net/ocf-02.htm 最老最基本的sustainable development：
1. Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs. It contains within it two key concepts:
- the concept of ‘needs’, in particular the essential needs of the world’s poor, to which overriding priority should be given; and
- the idea of limitations imposed by the state of technology and social organization on the environment’s ability to meet present and future needs.
2. Thus the goals of economic and social development must be defined in terms of sustainability in all countries – developed or developing, market-oriented or centrally planned. Interpretations will vary, but must share certain general features and must flow from a consensus on the basic concept of sustainable development and on a broad strategic framework for achieving it.
3. Development involves a progressive transformation of economy and society. A development path that is sustainable in a physical sense could theoretically be pursued even in a rigid social and political setting. But physical sustainability cannot be secured unless development policies pay attention to such considerations as changes in access to resources and in the distribution of costs and benefits. Even the narrow notion of physical sustainability implies a concern for social equity between generations, a concern that must logically be extended to equity within each generation.
……”In essence, sustainable development is a process of change in which the exploitation of resources, the direction of investments, the orientation of technological development; and institutional change are all in harmony and enhance both current and future potential to meet human needs and aspirations.”
Bruntland, G. (ed.), (1987)Our Common Future: Report of the World Commission on Environment and Development Oxford, Oxford University Press
http://www.article13.com/csr/aboutus.asp Article 13
There are over 100 definitions of sustainability and sustainable development, but the best known is the World Commission on Environment and Development’s. This suggests that development is sustainable where it “meets the needs of the present without compromising the ability of future generations to meet their own needs.”
————————————————————————————————————————————————-Strong sustainability regards natural capital as providing some functions that are not substitutable by man-made capital.These functions, labeled“critical natural capital”, are stressed by defining sustainability as leaving the future generations a stock of natural capital not smaller than the one enjoyed by the present generation. That is, sustainability is viewed in terms of non-decreasing natural capital. Following the definition proposed in Pearce and Atkinson (1993), an economy is considered sustainable if its savings rate is greater than the combined depreciation rate on natural and man-made capital. Under this notion, sustainability is equivalent to non-decreasing total capital stock.This is referred to as”weak” sustainability since no restrictions on the degree of sustainability between natural and man-made capital are introduced, and thus natural capital receives no special treatment.(无限制的可替换between自然资源和人为资源，自然资源也没特别处理）Consistent with this interpretations, Pearce and Atkinson (1993) present a weak sustainability index as an economic indicator of sustainable development. The weak sustainability index proposed is defined as the difference between the savings rate and the sum of the depreciation rate of natural and man-made capital.(什么经济术语，完全不懂我)……………The strong and weak concepts just outlined can be considered to represent two opposing ends in the quest to give a workable dimensions to sustainability.(Turner et al,1994),本文主要研究the key role of assumption on the degree of substitution between natural and man-made capital plays in building the concept of weak sustainability……
2.Growth theory with limited resources———-
Solow (1974) was to look at the conditions that conditions that would allow an economy to grow forever under the presence of limited natural resources. (研究某种在环境资源受限制，但经济无限增长的状态）…….no restrictions placed on the elasticity of substitution between any form of capital and the input….. Dasgupta and Heal (1979) In their model, natural resources are also essential inputs, but they allow for an unconstrained possibility of substituting natural capital for man-made capital. Taking this unlimited substitution into account, they are able to derive the result that exhaustible resources do not pose limits to growth, even in the absence of technological change. With the presence of technological change the possibilities of unlimited growth become even greater.(即使没有科技，自然资源受限也一样能够不影响和限制总资本的增长，如果有科技，那就更有可能无限的增长下去）……….Solow(1974) :允许economy在有限的资源条件下，无限的增长，这是有可能的，而且当下这一代可以利用有限的资源pool，只要我们不断创造新的capital
Hartwick (1977) and Solow (1986)….Solow(1986) savings-investment rule…he states that the conclusions are not easily extended when we have the presence of technological change and/or population growth, and that even if the rate of technological change is as large as the rate of population growth, the savings-investment rule still might not guarantee a constant level of consumption per capita.(Solow, 1986)after more than a decade later,说得好啊，这些人也有良心发现的时候，自己的理论还有看情况，科技发展和人口增长会限制他们所谓的无限制增长理论！！！！ 慢慢在变啊，从非常弱到弱的可持续发展理论 depreciation 翻译成消耗折旧！！！~~~
试试看 presented by Pearce and Atkinson (1993) , weak sustainability index can be viewed in terms of a “savings rule”, where constant or non-declining total capital stock is achieved by having the country’s savings for each period to be greater or equal to the sum of the depreciation on all forms of capital….(书中下方有解释：就是weak sustainability indicator includes the possibility of depreciation of all forms of capital, Stiglitz (1974) makes explicit this assumption by considering that we can either think of output as net output, or assume that there is no depreciation of man-made capital.(我们讲output，是在讲除掉资源和人为depreciation的总和之后，净产出）………..limitation！！！最后你发现不仅仅是之前说的那个科技进步和人口增长要限制 这群人的理论，现在要想想资源和经济之间的关系，因为你有时候也需要用自然资源去支持创造人为资本！！“need for natural capital to produce man-made capital” 自然资本绝对不是一个无止尽无限制的用，破坏它会增加你的成本投入，从而影响output总的capital. 结论是：考虑到这些因素，substitution没那么简单，变得困难了！所以退一步想想，我们不断消耗的状态constant stream在什么条件下是可以affordable的~~
以上种种得出key focus: “the conditions under which a constant stream of consumption per capita into the future could be guaranteed.”
从大的角度看“broader concern about the conflicts between economic activity and the environment, with special emphasis on inter-and intra-generational equity. That is the study of sustainability include a strong emphasis on distributional issues.”
1.Cobb-Douglas的functional form of weak sustainability是建立在高度替代的基础上的，（high degree of substitution between natural and man-made capital.) 忽略了环境和经济之间的矛盾，potential conflicts between economic development and environmental conservation. Victor (1991) ” the easier it is to substitute manufactured capital for depleting resources or a degrade environment, the less concern there need to be about the capacity of the environment to sustain development.”
（我的转述）资源难以加和的问题：capitalize的 natural和economic 资本不同功能，难以一起capitalized 成一个集合体.
Cabeza Gutés, M. (1996). The concept of weak sustainability. Ecological Economics, 17(3), 147-156.