On the Concept and Conservation of Critical Natural Capital

ABSTRACT

Ecological economics is an interdisciplinary science that is primarily concerned with developing interventions to achieve sustainable ecological and economic systems. While ecological economists have, over the last few decades, made various empirical, theoretical, and conceptual advancements, there is one concept in particular that remains subject to confusion: critical natural capital. While critical natural capital denotes parts of the environment that are essential for the continued existence of our species, the meaning of terms commonly associated with this concept, such as ‘non-substitutable’ and ‘impossible to substitute,’ require a clearer formulation then they tend to receive. With the help of equations and graphs, this article develops new definite account of critical natural capital that makes explicit what it means for objective environmental conditions to be essential for continued existence. The second main part of this article turns to the question of formally modelling the priority of conserving critical natural capital. While some ecological economists have maintained that, beyond a certain threshold, critical natural capital possesses absolute infinite value, absolute infinite utility models encounter significant problems. This article shows that a relative infinite utility model provides a better way to model the priority of conserving critical natural capital.

KEYWORDS:

• philosophy of ecological economics
• critical natural capital
• causation
• sustainability
• conservation
• non-standard decision theory

Acknowledgements

I wish to thank Josh Abbott, John Beatty, François Claveau, Eric Desjardins, Allen Habib, Andrew Inkpen, Stefan Lukits, Roberta Millstein, Luis Mireles Flores, Chris Mole, John O'Neill, Charles Perrings, Margaret Schabas, Chris Stephens, Beckett Sterner and two anonymous reviewers for helpful conversations and comments on earlier versions of this article. Special thanks to Paul Bartha for his remarkable erudition. Any errors are mine.

Notes

1 The International Society for Ecological Economics published the inaugural issue of Ecological Economics in 1989.

2 For the advancements made by ecological economists, see Christensen (1989); Martinez-Alier and Røpke (2008a), (2008b); Røpke (2005).

3 For the origins of this debate, see Beckerman (1994), (1995); Daly (1995); 1997a; 1997b); Solow (1997); Stiglitz (1997). For a detailed overview of the debate between weak and strong sustainability, see Neumayer (2003).

4 The ‘social scientific approach’ to sustainability was originally motivated by The World Commission on Environment and Development (1987). This approach was pioneered by Robert M. Solow (1986) and subsequently developed by David Pearce et al. (1989).

5 Specifically, sustaining the aggregate level of capital over time requires following Hartwick’s Rule whereby total net investment in capital remains above or equal to zero (Hartwick 1977, 1978). If net investment were to fall below this threshold, capital would be depleted and, because the stock of capital represents the productive capacity of an economy, production, along with the present and future human welfare that depends on it, would also decline (Arrow et al. 2004; 2010).

6 For additional arguments, see DesRoches (2019).

7 There is no consensus on the objects denoted by the concept of critical natural capital. Frequently cited examples include ‘freshwater resources,’ ‘climate regulation’ and ‘fertile soils’ (see Millenium Ecosystem Assessment 2005). Below, I will suppose ex hypothesi that the earth subsystem and processes identified by Johan Rockström et al. (2009a, 2009b) are instances of critical natural capital.

8 Rudolf de Groot et al. (2006, 221) consider some of the definitions listed here.

9 When proposing this particular definition, Pelenc and Ballet (2015) cite many other scholars likely to endorse it, including Ekins et al. (2003), Chiesura and de Groot (2003), de Groot et al. (2003) and Brand (2009).

10 For this purpose, I will mainly follow Christopher Hitchcock (2001).

11 Of course, the real epistemic benefit of equations and graphs is not merely the elegant representations of causal relations, but the clear and definite counterfactual reasoning they enable.

12 Clearly, the dependent variable Z could also be made to represent the continued existence or non-existence of a group. This possibility is discussed below.

13 It is to be remarked that the model merely represents causal knowledge. The knowledge itself is to be obtained somewhere else (earth and life sciences). This issue is discussed below.

14 The symbol ‘↔’ should read as ‘if and only if’. This definition can be read in light of J.L. Mackie’s (1980, 63) concept of a causal field: a set of background conditions, not completely specified but taken as fixed. The causal field fixes everything but some set of variables that one is interested in.

15 This group might consist of ‘all humans (i.e. humanity) or for a given human population or interest group in a given situation’ (de Groot et al. 2003, 190).

16 I will suppose an equal distribution of basic environmental conditions among members of G.

17 I will continue to suppose that critical natural capital denotes the earth-system subsystems, processes, and thresholds identified by Rockström et al. (2009a).

18 For more on the deontological approach and critical natural capital specifically, see Pearson, Kashima, and Pearson (2012); Baron and Spranca (1997); Tetlock et al. (2000).

19 For brevity, many details of RUT are omitted here. For further details, see Bartha (2007). My exposition of RUT closely follows Bartha and DesRoches (2017).

20 For a rehearsal of the standard axioms, see Resnik, M. D.: 1987, Choices, University of Minnesota Press, Minneapolis.

21 Below, I define what it means to value B infinitely relative to A and Z.

22 Why invoke a base-point here? One cannot define relative utility using gambles (as done here) without specifying the two alternatives (i.e., B and Z). As will be made clear below, the preferability of some outcome A over a gamble between B and Z will change depending on what the base-point is.

23 It is worth noting that because relative infinite utilities can be defined in terms of ordinary preferences between well-defined gambles, there is no need for calculations using positive or negative infinity.