We claim that a moral obligation to take climate leadership by means of unilateral mitigation depends on the existence of a plausible follow-the-leader mechanism whereby unilateral mitigation by some increases the probability of sufficient mitigation by others to avert catastrophic climate impacts. By understanding these mechanisms, we can better articulate the obligation for climate leadership across various sectors, from government to individual actors, in the fight against climate change. [Open access].

Solar radiation management (SRM) has been proposed as a means of mitigating climate change. Although SRM poses new risks, it is sometimes proposed as the ‘lesser evil’. I consider how research and implementation of SRM could be regulated, drawing on what I call a ‘precautionary checklist’, which includes consideration of the longer term political implications of technical change. Particular attention is given to the moral hazard of ‘regulatory drift’, in which strong initial regulation softens through complacency, deliberate deregulation (‘regulatory gift’) (...) and the limited constituency of people with the skills to regulate (‘thin markets’). I propose the strengthening of civil society groups to keep regulators in check. (shrink)

This paper explores what kind of uncertainty a research program governing solar climate engineering through Stratospheric Aerosol Injection (SAI) needs to account for. Specifically, it tries to answer two central issues with regards to SAI research and it’s ethical evaluation: One, what irreducible uncertainties remain throughout the decision-process, and, two, how do these remaining uncertainties affect the ethical evaluation of SAI research. The main assumption is that decisions on SAI research governance will be made under normative uncertainty, i.e. situations under (...) irreducible knowledge-constraints that arise in concrete, practical decision-contexts. These decision-contexts are multi-lateral and empirically ambiguous, and the decision-makers need to reconcile a plurality of values. While normative uncertainty complicates the ethical evaluation of policy decisions, I argue that moral considerations can be accommodated through the inclusion of recognitional, participatory justice approaches, as well as adaptive and anticipatory governance methods. (shrink)

According to some scholars, while sets of greenhouse gases emissions generate harms deriving from climate change, which can be mitigated through collective actions, individual emissions and mitigation activities seem to be causally insufficient to cause harms. If so, single individuals are neither responsible for climate harms, nor they have mitigation duties. If this view were true, there would be collective responsibility for climate harms without individual responsibility and collective mitigation duties without individual duties: this is puzzling. This paper explores a (...) way to solve this puzzle. First, it will be argued that individual emissions, though not proper and full-fledged causes, causally contribute to raise the probability of climate harms. As a consequence, individuals are in fact responsible for their expected contributions to climate harms – this is contributive responsibility for likely outcomes. Second, it will be argued that people have responsibility also for the possible impacts of their individual emissions on climate harms. People can plausibly be regarded as individually responsible for the possible outcomes of their actions in close possible alternative worlds – this is robust responsibility. Non-causal individual responsibility for climate harms is plausible, and the puzzle may be solved. (shrink)

A challenge faced by defenders of the precautionary principle is to clarify when the evidence that a harmful event might occur suffices to regard this prospect as a real possibility. Plausible versions of the principle must articulate some epistemic threshold, or de minimis requirement, which specifies when precautionary measures are justified. Critics have argued that formulating such a threshold is problematic in the context of the precautionary principle. First, this is because the precautionary principle appears to be ambiguous about the (...) distinction between risk and uncertainty: should the principle merely be invoked when evidential probabilities are absent, or also when probabilities have low epistemic credentials? Secondly, defenders of the precautionary principle face an aggregation puzzle: in judging whether or not the de minimis requirement has been met, how should first-order evidential probabilities and their second-order epistemic standing be aggregated? This article argues that the ambiguity can be resolved, and the epistemological puzzle can be solved. Focusing on decisions in the context of climate uncertainty, I advance a version of the precautionary principle that serves as a plausible decision rule, to be adopted in situations where its main alternative—cost–benefit analysis—does not deliver. (shrink)

This article examines the relationship between the precautionary principle and the well-known Hill criteria of causation. Some have charged that the Hill criteria are anti-precautionary because the...

This article explores the consequences of falling costs of solar and wind power for the ethics of climate change mitigation. We suggest that price competitiveness of renewables reveals a divergence of interest between fossil fuel consumers and producers: cheap renewables strengthen precautionary arguments for aggressive mitigation for consumers but threaten the economic base of producers. As existing applications of the precautionary principle to climate change do not address this issue, we develop a novel approach based on lexical utilities. Given the (...) premise that climate catastrophe entails economic catastrophe but not vice versa, we argue that both producers and consumers should favor mitigation. (shrink)

The precautionary principle (PP) is an influential principle for making decisions when facing uncertain, but potentially severe, harm. However, there is a persistent disagreement about what the principle entails, exactly. It exists in a multitude of formulations and has potentially conflicting ideas associated with it. Is there even such a thing as ‘the precautionary principle’? This paper analyses the debate between unificationists and pluralists about ‘the PP’, arguing that the debate is hindered by neglecting the question of justification. It introduces (...) reflective equilibrium as a method of justification, and sketches how it could be applied to justify a PP. (shrink)

Antimicrobial resistance has been termed a ‘silent pandemic’, a ‘hidden killer.’ This language might indicate a threat of significant future harm to humans, animals, and the environment from resistant microbes. If that harm is uncertain but serious, the precautionary principle might apply to the issue, and might require taking ‘precautionary measures’ to avert the threat of antimicrobial resistance, including stewardship interventions like antibiotic prescription caps, bans on certain uses in farming sectors, and eliminating over-the-counter uses of antibiotics. The precautionary principle (...) is a useful tool in ethical analyses of antimicrobial stewardship measures, but as I argue in this article, it ought not be used as a standalone tool. The principle considers the magnitude of harms to be averted and those arising from precautionary measures, but—importantly—it does not consider the distribution of those harms. That may raise issues of social justice if the harms of stewardship measures befall already disadvantaged populations. To avoid this blind spot in ethical analysis using the precautionary principle, it ought never be used alone, but rather always alongside justice-considering ethical concepts such as reciprocity, benefit-sharing, or a just transition. (shrink)