“First Come, First Served”
The second objection to corrective justice emerges from a disanalogy. In the pizza case, you have a clear right to the eaten slices, because you have already paid for them. With emissions, it might be argued that latecomers have no such claim. Perhaps it is simply “first come, first served,” and hard luck to the tardy.
In my view, this response is too quick. We must ask what initially justifies policies like “first come, first served.” Consider one natural explanation. If a resource initially appears to be unlimited, consumers may simply assume that no issues of allocation arise. Everyone can take whatever they want, with no adverse consequences for others. In this case, the principle is not really “first come, first served” (which implies that the resource is limited, so that some may lose out), but rather “free for all” (which does not). Since it is assumed that there is more than enough for everyone, no principle of allocation is needed.
In such a case, what happens if the assumption that the resource is unlimited turns out to be mistaken, so that “free for all” becomes untenable? Do those who have already consumed large shares have no special responsibility to those who have not and now cannot? Does the original argument for “free for all” justify ignoring the past? I think not. If the parties had considered at the outset the possibility that the resource might turn out to be limited, which allocation principle would have seemed more reasonable and fair: “free for all, with no special responsibility for the early users if the resource turns out to be limited,” or “free for all, but with early users liable to extra responsibilities if the assumption of unlimitedness turns out to be mistaken”? Offhand, there seem clear reasons to resist ignoring the past: it makes later users vulnerable in an unnecessary way, and provides a potentially costly incentive to consume early and often if possible. Given this, “first come, first served” looks unmotivated. Why adopt an allocation rule that so thoroughly exempts early users from responsibility?