As we’ve written previously, we aim to extend empathy to every being that warrants moral concern, including animals. And while many experts, government agencies, and advocacy groups agree that some animals live lives worthy of moral concern, there seems to be little agreement on which animals warrant moral concern. Hence, to inform our long-term giving strategy, I’ve prepared a new report on the following question: “In general, which types of beings merit moral concern?” Or, to phrase the question as some philosophers do, “Which beings are moral patients?”

For this preliminary investigation, I focused on just one commonly endorsed criterion for moral patienthood: phenomenal consciousness, a.k.a. “subjective experience.” I have not come to any strong conclusions about which (non-human) beings are conscious, but I think some beings are more likely to be conscious than others, and I make several suggestions for how we might make progress on the question.

In the long run, to make well-grounded decisions about how much we should value grants aimed at (e.g.) chicken or fish welfare, we need to form initial impressions not just about which creatures are more and less likely to be conscious, but also about (a) other plausible criteria for moral patienthood besides consciousness, and also about (b) the question of “moral weight.” However, those two questions are beyond the scope of this initial report on consciousness. In the future I hope to build on the initial framework and findings of this report, and come to some initial impressions about other criteria for moral patienthood and about moral weight.

My goals for this report on consciousness and moral patienthood were to:

1. survey the types of evidence and argument that have been brought to bear on this question,
2. briefly describe example pieces of evidence of each type, without attempting to summarize the vast majority of the evidence (of each type) that is currently available,
3. report what my own intuitions and conclusions are as a result of my shallow survey of those data and arguments,
4. try to give some indication of why I have those intuitions, without investing the months of research that would be required to rigorously argue for each of my many reported intuitions, and
5. list some research projects that seem (to me) like they could make progress on the key questions of this report, given the current state of evidence and argument.

The report’s first section explains how to read the report, including brief descriptions of each section and major appendix.

In short, my tentative conclusions are that I think mammals, birds, and fishes are more likely than not to be conscious, while (e.g.) insects are unlikely to be conscious. However, my probabilities are very “made-up” and difficult to justify, and it’s not clear to us what actions should be taken on the basis of such made-up probabilities.

For more details, see the full report.