Daly, Herman E. 1995. "On Wilfred Beckerman's Critique of Sustainable Development." Environmental Values 4(1995): 49-55.

Thesis:

Daly responds to Beckerman's (1993) critique of sustainable development by agreeing with his rejection of 'weak sustainability' and by defending 'strong sustainability'. Daly focuses his attention on the question of whether human made capital and natural capital are basically substitutes or complements.

Summary:

Daly distinguishes between 'weak sustainability' and 'strong sustainability' in that the former assumes that natural capital and human made capital are basically substitutes. In contrast, 'strong sustainability' assumes that the two forms of capital are complementary. He charges that Beckerman believes that 'strong sustainability' means that no resource will ever be ultimately depleted or pushed toward extinction. (P.49). The crucial question is then, are natural and manmade capital substitutes, or are they complements?

If the two forms of capital are complements, then the resource in short supply would be a limiting factor. Historically, in the 'empty world' paradigm, human made capital has been the limiting factor. However, since we have entered into a 'full' world era, natural capital has become the limiting factor. Based upon economic logic, we economize, and put constraints on the use of the input that is in limited supply. Thus, natural capital requires a real substitute, rather than a financial one. (pp.50,51).

Daly defends the principal of complementarity on the following three arguments (p.51):

If natural capital were a near perfect substitute for manmade capital, there would have been no reason to develop human made capital in the first place.

Manmade capital is a transformation of natural capital. Thus, to produce more human made capital, it is necessary to utilize more natural capital, making the two complements, by definition.

The natural inputs are the material cause of production. The capital stock that transforms these natural inputs is the efficient cause of production. One cannot use half the amount of timber to build a house, no matter how efficient labor and human made capital are.

In common sense terms, Daly asks, "what good is a saw-mill without a forest?" The two are complements, not substitutes.

Daly then turns to Beckerman's recommendation to utilize discounting as a means to balance present and future claims on the resource base. Daly argues that discounting is part of a price system for a given distribution of ownership. Future generations have no claim to this ownership. We should "keep natural capital intact," distinct from human made capital, since they are complements, not substitutes (p.53). Strong sustainability would extend the system of ownership across the generations. Hence, the rights of future generations are better protected, by passing on the physical requirements for potential production (p.50).

Daly concludes that sustainable development as a concept, while vague at times, is at least as clear as the concept of 'money', and it is indispensable (p.54).

Keywords: strong sustainability, substitutionality, complementarity, natural capital, manmade capital.