Toby Svoboda

Although it could avoid some harmful effects of climate change, sulphate aerosol geoengineering (SAG), or injecting sulphate aerosols into the stratosphere in order to reflect incoming solar radiation, threatens substantial harm to humans and non-humans. I argue that SAG is prima facie ethically problematic from anthropocentric, animal liberationist, and biocentric perspectives. This might be taken to suggest that ethical evaluations of SAG can rely on Bryan Norton's convergence hypothesis, which predicts that anthropocentrists and non-anthropocentrists will agree to implement the same or similar environmental policies. However, there are potential scenarios in which anthropocentrists and non-anthropocentrists would seem to diverge on whether a particular SAG policy ought to be implemented. This suggests that the convergence hypothesis should not be relied on in ethical evaluation of SAG. Instead, ethicists should consider the merits and deficiencies of both non-anthropocentric perspectives and the ethical evaluations of SAG such perspectives afford

If deployed, aerosol geoengineering (AG) could involve unfairness to both present and future parties. I discuss three broad risks of unfairness that an AG deployment policy might carry: (1) causing disproportionate harm to those least responsible for climate change, (2) burdening future parties with the costs and risks of AG, and (3) excluding some interested parties from contributing to AG decision-making. Yet despite these risks, it may be too hasty to reject AG deployment as a potential climate change policy. I argue that since it is very unlikely that a completely fair climate change policy will be pursued, we have ethical reason to prefer some “incompletely fair” policy. Given various facts about our world, it might be the case that some AG policy is ethically preferable to many other feasible climate change policies, even if AG carries deeply problematic risks of unfairness.

According to the “Lesser of Two Evils Argument,” deployment of solar radiation management (SRM) geoengineering in a climate emergency would be morally justified because it likely would be the best option available. A prominent objection to this argument is that a climate emergency might constitute a genuine moral dilemma in which SRM would be impermissible even if it was the best option. However, while conceiving of a climate emergency as a moral dilemma accounts for some ethical concerns about SRM, it requires the controversial claim that there are genuine moral dilemmas, and it potentially undermines moral action guidance in emergency scenarios. Instead, it is better to conceive of climate emergencies as situations calling for agent-regret. This alternative allows us coherently to hold that SRM may be morally problematic even if it ought to be deployed in some scenario.

This book analyzes major ethical issues surrounding the use of climate engineering, particularly solar radiation management (SRM) techniques, which have the potential to reduce some risks of anthropogenic climate change but also carry their own risks of harm and injustice. The book argues that we should approach the ethics of climate engineering via "non-ideal theory," which investigates what justice requires given the fact that many parties have failed to comply with their duty to mitigate greenhouse gas emissions. Specifically, it argues that climate justice should be approached comparatively, evaluating the relative justice or injustice of feasible policies under conditions that are likely to hold within relevant timeframes. Likely near-future conditions include "pessimistic scenarios," in which no available option avoids serious ethical problems. The book contends that certain uses of SRM can be ethically defensible in some pessimistic scenarios. This is the first book devoted to the many ethical issues surrounding climate engineering.

According to indirect duty views, human beings lack direct moral duties to non-human organisms, but our direct duties to ourselves and other humans give rise to indirect duties regarding non-humans. On the orthodox interpretation of Kant’s account of indirect duties, one should abstain from treating organisms in ways that render one more likely to violate direct duties to humans. This indirect duty view is subject to several damaging objections, such as that it misidentifies the moral reasons we have to treat non-humans in certain ways and that it sanctions only weak obligations vis-à-vis organisms. I develop an alternative indirect duty view: given a direct duty to oneself to cultivate virtuous dispositions, one has an indirect duty to abstain from treating organisms in ways that erode one’s virtues or develop vices. I argue that this indirect duty view strictly proscribes knowingly causing unnecessary harm to organisms, and I show that it is not subject to the damaging objections directed against the indirect duty view attributed to Kant by the orthodox interpretation. This suggests that indirect duty views are more worthy of consideration than is often supposed.

Philosophers should consider a hybrid meta-ethical theory that includes elements of both moral expressivism and moral error theory. Proponents of such an expressivist-error theory hold that all moral utterances are either expressions of attitudes or expressions of false beliefs. Such a hybrid theory has two advantages over pure expressivism, because hybrid theorists can offer a more plausible account of the moral utterances that seem to be used to express beliefs, and hybrid theorists can provide a simpler solution to the Frege-Geach problem. The hybrid theory has three advantages over pure error theory, because hybrid theorists can offer a more plausible account of the moral utterances that seem to be used to express attitudes, hybrid theorists can more easily explain moral motivation, and hybrid theorists can avoid the implausible claim that all moral discourse is radically mistaken. Accordingly, such a hybrid theory should be more attractive than pure expressivism or pure error theory to philosophers who are skeptical about moral facts and truth.

Many philosophers have objected to Kant’s account of duties regarding non-human nature, arguing that it does not ground adequate moral concern for non-human natural entities. However, the traditional interpretation of Kant on this issue is mistaken, because it takes him to be arguing merely that humans should abstain from animal cruelty and wanton destruction of flora solely because such actions could make one more likely to violate one’s duties to human beings. Instead, I argue, Kant’s account of duties regarding nature grounds much stronger limitations on how humans may treat non-human animals and flora, since such duties are rooted in the imperfect duty to increase one’s own moral perfection. This duty proscribes actions affecting non-human nature that decrease one’s moral perfection, such as those that cause organisms unnecessary harm. Moreover, the duty to moral perfection prescribes (but does not strictly require) actions affecting non-human nature that increase one’s moral perfection, such as those that benefit organisms. Given this interpretation, I show that, contrary to a widely held view, Kant’s moral philosophy can ground a coherent and robust approach to environmental ethics.