How to measure capacity for welfare and moral status (Rethink Priorities)

An animal’s capacity for welfare is how good or bad its life can go. An animal’s moral status is the degree to which an animal’s experiences or interests matter morally. It’s plausible that animals differ in their capacity for welfare and/or their moral status. These differences could affect the way we ought to allocate resources across interventions and/or cause areas. Unfortunately, measuring capacity for welfare and moral status is tremendously difficult.

When donors or researchers choose to focus on cause areas or interventions that target certain species rather than others, they are often implicitly making judgments about the comparative value of different animals (including humans). Without a model for quantifying differences in comparative value, such judgments are apt to be guided by imperfect and likely unreliable heuristics.

There are two non-exclusive methods we might employ to measure capacity for welfare and moral status. The first method is to survey various experts about what sort of tradeoffs among animals they would endorse. This approach is relatively simple and cheap, but it relies on the assumption that intuitions about moral tradeoffs reliably track the moral truth. This assumption looks dubious. Intuitive judgments of this kind are often sensitive to non-evidential factors. Deep-rooted, widespread speciesism is likely to prejudice responses.

The second method is more time-consuming and complex but potentially more objective. The method proceeds in three steps. The first step is to canvass the relevant philosophical literature to generate a relatively theory-neutral list of characteristics that might contribute to capacity for welfare or moral status. The second step is to find empirically measurable proxies for those characteristics and weight the proxies by their relative importance. The third step is to canvass the relevant scientific literature to score different animals of interest according to the features identified in the second step. Estimates of uncertainty would be made at each step, and a sensitivity analysis would help identify areas of high information value. I estimate that such a project would require between five thousand and seven thousand person-hours to complete.