Читать книгу The New Environmental Economics - Eloi Laurent - Страница 13

“Planetary boundaries” are quantitative thresholds “within which humanity can continue to develop and thrive for generations to come.” Crossing these boundaries entails the risk of generating large-scale abrupt or irreversible environmental changes. Scientists warned us recently that “Four of nine planetary boundaries have now been crossed as a result of human activity: Climate change, loss of biosphere integrity, land-system change, altered biogeochemical cycles (phosphorus and nitrogen).” Two of these, climate change and biosphere integrity, are “core boundaries.” Significantly altering either of these would “drive the Earth System into a new state.”⁷ This is certainly breakthrough science, yet the classical economists from the eighteenth and nineteenth centuries had the intuition that human development was in fact constrained by the scarcity of Nature.

What has been referred to as the “grandiose dynamic” of the English classical school (whose major triad includes Adam Smith, David Ricardo, and John Stuart Mill) is based on the assumption of the domination of Man by Nature. In the view of the authors, Man does not (cannot) destroy Nature: He takes advantage of his fertility but, in return, Nature imposes on him his rhythm of exploitation and his finitude, and promises him a stationary state as an horizon. According to the classics, economic growth is only possible as long as all available land is not exploited, agricultural productivity being a gift that cannot be manipulated by technological progress.

It is not the prospect of the deterioration of natural resources, let alone the depletion of natural stocks, that leads to the melancholic conclusion of the classics, but the comparison between what the Earth can offer and what it takes for humans to subsist. The analysis of Malthus was the most accomplished expression of this disillusioned comparison before David Ricardo developed his idea of “diminishing returns” and John Stuart Mill his vision of the “stationary state.”

The work of David Ricardo (1817) is indeed profoundly marked by Malthus’ (wrong and not so wrong) reasoning. But Ricardo refined it considerably by formulating his theory of agricultural rent. In his analysis, the scarce resource is, quite naturally, agricultural land whose limited availability in the United Kingdom was glaring, while the industry just began its take off. Ricardo framed his famous reasoning in terms of “differential rent”: The most fertile lands are the first to be cultivated, but, as the pressure of demand increases because of the increase of the population, less fertile land must be exploited. Because these new lands are less productive, their unit cost of production is higher, so the selling price required for production on these new lands is also higher. But the market price being unique, the owners of the most fertile land benefit from a “differential” rent. “Diminishing returns” occur because of the lower productivity of the lands gradually being cultivated under the pressure of the consumption of their yields by a growing population.

Ricardo saw globalization and technological progress as solutions to the law of diminishing returns. But he had more confidence in trade than in technology. Considerably refining and extending the “absolute advantages” of Adam Smith,⁸ he greatly enlarged the circle of countries that could beneficially take part in globalization (potential partners of his home country). He also thought that if agricultural innovations would accelerate (as will be the case throughout the twentieth century), then diminishing returns could be overcome. But Ricardo envisioned a “steady state” of the economy, at the very end of Chapter V of the Principles of Political Economy, where neither globalization nor progress in techniques operate any longer. John Stuart Mill will push the idea much further in the middle of the nineteenth century, all the while the first industrial revolution was booming all around him.