I argue that the use of a social discount rate to assess the consequences of climate policy is unhelpful and misleading. I consider two lines of justification for discounting: (i) ethical arguments for a "pure rate of time preference" and (ii) economic arguments that take time as a proxy for economic growth and the diminishing marginal utility of consumption. In both cases I conclude that, given the long time horizons, distinctive uncertainties, and particular costs and benefits at stake in the (...) climate context, discount rates are at best a poor proxy for the normative considerations they are meant to represent. (shrink)

Both intertemporal and intratemporal equity are central to the examination of policy towards climate change. However, many discussions of intertemporal issues have been marred by serious analytical errors, particularly in applying standard approaches to discounting; the errors arise, in part, from paying insufficient attention to the magnitude of potential damages, and in part from overlooking problems with market information. Some of the philosophical concepts and principles of Paper 1 are applied to the analytics and ethics of pure-time discounting and infinite-horizon (...) models, providing helpful insights into orderings of welfare streams and obligations towards future generations. Such principles give little support for the idea of discrimination by date of birth. Intratemporal issues are central to problematic and slow-moving international discussions and are the second focus of this paper. A way forward is to cast the policy issues and analyses in a way that keeps equity issues central and embeds them in the challenge of fostering the dynamic transition to the low-carbon economy in both developed and developing countries. This avoids the trap of seeing issues primarily in terms of burden-sharing and zero-sum games – that leads to inaction and the most inequitable outcome of all. (shrink)

This paper puts forward two claims about funding carbon capture and storage. The first claim is that there are moral justifications supporting strategic investment into CO2 storage from global and regional perspectives. One argument draws on the empirical evidence which suggests carbon capture and storage would play a significant role in a portfolio of global solutions to climate change; the other draws on Rawls' notion of legitimate expectations and Moellendorf's Anti-Poverty principle. The second claim is that where to pursue this (...) strategic investment poses a morally non-trivial problem, with considerations like near-term global distributive justice and undermining legitimate expectations favouring investing in developing regions, especially in Asia, and considerations like long-term climate impacts and best uses of resources favouring investing in the relatively wealthy regions that have the best prospects for successful storage development. [Open access]. (shrink)

John Broome and Duncan Foley have argued that it is a ‘misperception’ that the ‘control of global warming is costly’ and that we can make ‘sacrifices unnecessary’. There are a number of assumptions that are essential for this idea to work. These assumptions can be challenged. Furthermore, my claim is not merely that the Broome/Foley argument is flawed, and therefore unlikely to be successful. I will argue that it is potentially harmful, leading to harms for the present generation and for (...) future generations. (shrink)

John Broome claims that there is a sacrifice-free solution to climate change. He says this is a consequence of elementary economics. After explaining the economic argument in somewhat more detail than Broome, I show that the argument is unsound. A main problem with it stems from Derek Parfit's ‘nonidentity effect.’ But there is hope, since the nonidentity effect underwrites a more philosophical yet more plausible route to a sacrifice-free solution. So in the end I join Broome in asking economists and (...) policymakers to help make this a reality. (shrink)

Recent debates over climate change policy have made it clear that the choice of a social discount rate has enormous consequences for the amount of mitigation that will be recommended. The social discount rate determines how future costs are to be compared to present costs. Philosophers, however, have been almost unanimous in endorsing the view that the only acceptable social rate of time preference is zero, a view that, taken literally, has either absurd or extremely radical implications. The first goal (...) of this paper is to show that the standard arguments against temporal preference are much less persuasive than they are usually taken to be. The second goal is to explore two different avenues of argument that could be adopted, in order to show that temporal discounting of welfare may be permissible. The first involves simply an application of the method of reflective equilibrium, while the second involves consideration of the way that our abstract moral commitments are institutionalized. (shrink)

This paper delves into the work of Clive L. Spash, a British radical ecological economist well-known in his field who currently holds a professorship at the Vienna University of Economics and Business. We start with an examination of the principles of his “social ecological economics.” We then critically evaluate his attack on economic growth and his perspective on the standard economic models of climate change. Lastly, we explore his approach to science as a theoretical pursuit and his policy recommendations. The (...) first version of this paper was given as a keynote lecture at the 7th Austrian Economics Meeting Europe, May 12-13, 2023, Université Catholique de l’Ouest, Angers, France, and a second version at the Summer University in Political Economy, July 20-22, 2023, Aix-Marseille University, France. I wish to thank the organizers of these conferences, and also the anonymous referees whose remarks have been taken into account to improve the paper. (shrink)

I discuss three families of methodologies that could be used to assign values to the normative parameters relevant to social discounting in welfare economics generally, and climate economics more specifically. First, I argue that in particular circumstances, there cannot be philosophical argumentation for normative questions; specifically, this occurs when the particular values being sought are both non-critical and from a quantitative range. Second, I argue that social preferences are insufficient if we take the problem to be normative and that proposals (...) for informed social preferences face significant challenges in implementation. Finally, I argue in favour of expert elicitation for experts in welfare economics, construed as those who understand the theoretical implications of adopting particular judgments. Those who understand the theoretical implications of adopting particular judgments will be better placed to develop coherent social plans while integrating relevant empirical data. (shrink)