Natural capital and anthropogenic capital are treated as independents, but anthropogenic capital is dependent on, and draws from, the natural capital resource base for its maintenance and expansion. Technology can substitute for a decline in natural capital; or at least, that within fixed environmental constraints, new technology can facilitate an increase in productivity within those parameters. A similar view holds that a depreciation of natural capital can be compensated for by an increase in man-made (anthropogenic) capital. For example, material scarcity is no longer an issue when current technological developments substitute abundant supplies of carbon and silicon for less abundant materials such as copper and zinc.
There are two lines of thought that follow from this. One is a tolerance of natural capital depletion by ignoring ethical considerations and the intrinsic non-monetary value of nature and ecosystems irrespective of their worth to economic output. The second is that greater reliance on anthropogenic capital can reduce depreciation of natural capital (e.g. recyclable synthetic paper to replace paper derived from logging primary growth forests).
Limits to growth proponents argue that the elasticity of substitution is less than one, in some cases far less, leading to a decreasing marginal product of capital, ie as natural capital is depleted a proportionately greater amount of (anthropogenic) capital is required per unit output).