Thank you all for the interesting and helpful feedback. Michael mentions a case (a methane tipping point) in which deployment of SAG might satisfy requirements of justice. Perhaps in certain scenarios, SAG would be (or would be part of) a just climate policy, or at least a policy that is less unjust than other policies available in those scenarios. Our paper is rather preliminary in the sense that it raises some ethical worries about SAG but does not take a position on whether it ought to be deployed. Perhaps, even with certain ethical imperfections, in some likely scenarios SAG would be the best option from a justice perspective. I don't know whether this would be the case. It seems that further work would be needed to get clear on that.
As for unilateralism, our paper does not argue that there is a high probability of unilateral deployment but rather that such deployment would be unjust. As you know, there are a number of papers in the literature that discuss unilateral deployment. Josh's paper (which appeared after ours was in press) and Dan's comments raise some interesting points. Perhaps worries over unilateralism are overblown. That would be a welcome result from a procedural justice perspective, although non-unilateral deployment wouldn't necessarily be procedurally just (e.g., if some other countries, through no fault of their own, were still excluded from having a say in whether and how SAG gets deployed). Both Michael and Josh suggest that actual policies often violate the theories of procedural justice we consider in the paper. This may well be true, but that does not mean that those theories are false. What we actually do and what we ought to do are distinct--we can fail to live up to standards we should meet. Moreover, it seems that a policy could be more or less procedurally unjust, with the latter being ethically preferable to the former. For example, one could treat the Rawlsian principle as an ideal--even if it is rarely complied with perfectly, some decision procedures will come closer than others. Dan mentions a number of concerns, but I wouldn't characterize our paper as containing "objections" to SAG, because we don't advocate that it ought not to be deployed. In the sections on distributive and intergenerational justice, we point to risks of harm associated with SAG. We think these risks are ethically significant and should be taken into account. All things considered, it might turn out that these are risks that should be tolerated, but that remains to be shown in my view. Dan writes, "But on the whole, the suggested program of incremental research, followed possibly by limited testing, seem a sensible approach when we compare the risks of implementation against a world which is clearly warming in a dangerous way?" We don't deny this in the paper, as we focus on deployment rather than research. Dan also writes, "The idea that the question of intergenerational justice might be one where we're *disadvantaging* future generations seems likewise odd. After all, the whole reason this is being proposed is in large part because of concerns about the well being of future generations." But even if our intentions are good (e.g., the well-being of future persons), we can still cause substantial harm to persons. Again, perhaps we ought to deploy SAG, e.g. because the harm to future generations would be less if we do than if we do not. But if so, it is my view that an argument for that would need to be made in detail. Many Thanks, Toby -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
