So I know I haven't posted anything on my struggles with the Non-Identity Problem (first conceived by Derek Parfit), so I figure this is as good a time as any. As it applies to the issue of climate change, the Non-Identity Problem manifests itself like this:
If we were to act to prevent or mitigate climate change, we would bring it about that people would spend their money on different things, travel to different places, meet different people, get different jobs, and most importantly, have different children (just think how tiny are the chances of a particular spermatozoon fertilizing a particular egg!). In 100 years, it's likely (if not certain) that the world would be populated by an entirely different set of people.
As a consequence of this "fact" (I will accept it as one), we are pretty much forced to say that the people who inherit a world affected by climate change are no worse off than they could have been, because if we had caused less climate change, they wouldn't have existed. Accordingly, it seems difficult to see how we could say that climate change "harms" anyone; if we did anything differently "to" them, they'd simply not exist.
Libertarian conceptions of justice generally hold that if something doesn't harm anyone, then it can't be considered "unjust" (where we accept the view, as Peter Vallentyne suggested on page two of Left-Libertarianism and its Critics, that "...an action is unjust if and only if others are morally permitted to coerce one not to perform it"). So if we can't say that climate change harms anyone, we might be forced to say that it's perfectly just (though perhaps we might still lament it or consider it immoral for people to contribute to it). But is there really no way to say that climate change harms anyone?
In his essay, "Liability, Responsibility, and Harm," Dan Hausman suggests three different conceptions of "harm." He writes, "...one might take A to harm B whenever A diminishes B's budget set or A interferes with or damages any of B's capacities. B's budget set is the set of all possible outcomes obtainable by B, provided that B's capacities are unimpaired. To simplify somewhat, one can take A to harm B whenever A limits B's options." He continues, "This notion of harm as limiting options contrasts with two other notions: harm as decreasing utility and harm as violating rights."
It's clear that the first conception of harm as limiting options can not be appealed to in discussing climate change. If we suppose that doing anything differently would cause the alleged "victims" of climate change to never exist, it's easy to see why we wouldn't want to say that their options are in any way limited by our causing climate change. In fact, they only have options because we caused climate change.
The second view, of harm as a decrease in wellbeing or utility, fails to work here for similar reasons. When we say that we make people worse off by causing climate change, we must appeal to a counterfactual regarding what would have happened if we hadn't caused climate change. But it's hard to see how we would want to say that someone is "worse off" if there would have been no possible way to make them "better off" than they are already being made by our actions.
So the only view left is to say that future people might be being harmed by climate change because climate change violates their rights. But how can you say that people have the right to something that couldn't have happened? That is, to say that someone's rights are "violated" suggests a comparison to some kind of baseline. I'll illustrate with an example from Judith Thomson's book, Rights, Restitution, & Risk: Essays in Moral Theory. In her chapter on "Self-Defense and Rights," Thomson writes, "Suppose a man has a right that something or other shall be the case; let us say that he has a right that p, where p is some statement or other, and now suppose that we make p false. So, for example, if his right is the right that he not be punched in the nose, we make that false, that is, we bring about that he is punched in the nose. Then, as I shall say, we infringe his right. But I shall say that we violate his right if and only if we do not merely infringe his right, but more, are acting wrongly, unjustly in doing so." (I don't want to address the question of whether causing climate change would be better thought of as an infringement or a violation, though I do have more to say about that. For now, I'll say that if I can show that we infringe a right held by future people by causing climate change, then this exercise will be a success. But as long as I'm not quoting anyone else, I'll try to use the word "infringe" so as to avoid objections.)
In light of Thomson's characterization, it seems difficult to see why we would suppose future people to have a right that something happen if it wouldn't be possible for that to happen and for them to exist. In other words, let's say climate change is going to cause more floods in Pedro's village, and let's say that we're wondering whether Pedro has the right to not have those floods be caused. If we could say that preventing those floods from happening would also prevent Pedro from ever existing, it's unclear that we would have any basis for upholding such a right on Pedro's behalf.
It should be clear what kind of right we would intuitively want to appeal to when we're talking about climate change: the right to inherit an Earth which has not been made more dangerous and inhospitable by intentional, non-critically important or necessary, self conscious human activities. But if a person born into a more dangerous world would never have been born if the world were not made more dangerous in the way that it was, then how could such a person complain? How can we talk about a right which doesn't involve either of the first two kinds of harm? I'm finding it extremely difficult to find an answer.
But John Broome offers a helpful suggestion in his book, Counting the Cost of Global Warming. He writes, "One way this thought might be rescued from the nonidentity problem is to recognize that the owners of rights are not necessarily individual people. It seems that nations have rights. Kuwait has a right not to have its territory seized, and this right seems separate from the rights of the individual citizens of Kuwait. It will survive even when the entire present population of Kuwait has died, and been replaced with a new population. Perhaps the rights of a generation might be conceived in a similar way." Libertarians are sure to bristle at the analogy of Kuwait having rights. After all, in Anarchy, State, and Utopia, Robert Nozick wrote, "...no new rights "emerge" at the group level...individuals in combination cannot create new rights which are not the sum of preexisting ones," and most (if not all) libertarians agree.
But before deciding whether to accept or reject this sort of notion, we should take a look at what kind of thing Broome might have had in mind. Let's call the set of all "possible people" who could have existed at some future point in time "Generation L." If Generation L has the right to inherit an "unspoiled" Earth, then if we bring it about that the Earth is "spoiled" by our actions, then we infringe upon Generation L's rights. This would result in Generation L being manifested as some group of people, all of whom would not have existed in a scenario in which the Earth was unspoiled. But since the rights are held by Generation L, and not by the individuals who represent L in the spoiled-Earth scenario, we can still say that a rights infringement has occurred, even if we wouldn't be able to say that any representative of L has had his/her rights infringed upon.
And to be completely honest, it seems like this sort of thing is exactly what people mean when they say that we're doing something wrong by causing climate change. So does this go against Nozick's claim that there are no emergent rights? And if so, what does that mean? Which side should we come down on?
Let's say, for the sake of discussion, that we don't immediately reject this view. Because we're saying that we're infringing upon the rights of "Generation L" and also that we're not infringing the rights of any of the people who represent Generation L in the spoiled-Earth scenario, it's unclear what it even means to say that we've infringed upon the rights of Generation L. What obligations does such an infringement impose on us? Are we acting wrongly (that is, violating Generation L's rights) if we spoil the Earth?
On the other hand, what would it mean to reject this view? Would we need to conclude that there isn't any basis for coercive prevention of climate change?
Obviously, there's a whole lot more to be said about all of this. But hopefully this will get the ball rolling. I'm going to be meeting with Dr. Hausman (mentioned above) tomorrow, and hopefully he'll have something to add.