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Rethink Priorities

Broadening our moral circles: Understanding welfare capacities

Rachel Norman, Henri Thunberg
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Donors committed to making a difference need strong evidence and empirical methods to make informed decisions about how to allocate resources.

Should you donate to programs that help humans or animals? If animals, which species? Answering these questions requires us to compare the overall quality of life that different species can experience (i.e. their capacity for welfare). Using unrestricted funding, Rethink Priorities launched the Moral Weight Project to meet this need. Via a multidisciplinary approach, the research team found the estimated welfare capacities of the species they examined to be relatively similar to one another. Our rigorous investigation resulted in the creation of the welfare range table—an accessible model that some foundations and governments have begun using to help them make better decisions.

11

farmed species were examined as a part of the Moral Weight Project

90

empirical traits were considered as a part of the researchers’ welfare capacity considerations

9

RP reports explain our research team’s findings on this project

Understanding welfare capacities

The research process

Comparing welfare across species is both a profound philosophical challenge and a crucial practical concern.

To tackle this challenge, our researchers surveyed hundreds of studies as a basis to how much we should weigh the suffering of a range of animals and humans. The team shared their findings in a sequence of articles with the aim of providing people with a transparent foundation for prioritization.

  1. An introduction to the project explains the potential implications of the research on allocations between different animals as well as between humans and other animals.
  2. The welfare range table provides an overview of the results of a literature review covering over 90 empirical traits across 11 farmed species.
  3. Theories of welfare and welfare range estimates suggests a way to quantify the impact of assuming hedonism on welfare range estimates.
  4. Why neuron counts shouldn’t be used as proxies for moral weight summarizes a full report on this issue.
  5. Do Brains Contain Many Conscious Subsystems? If So, Should We Act Differently? recommends not acting on the hypothesis that brains contain conscious subsystems at this time.
  6. Octopuses (Probably) Don’t Have Nine Minds argues that there is insufficient evidence to assume that certain species (e.g. octopuses) “house” multiple welfare subjects per individual. This post is a summary of a full report on phenomenal unity and cause prioritization.
  7. Don’t Balk at Animal-friendly Results warns against dismissing research just because its findings suggest that certain species can realize roughly the same amount of welfare as humans (called “the Equality Result”).
  8. Rethink Priorities’ Welfare Range Estimates recaps the team’s understanding of welfare ranges and their proposed way of using them, and addresses methodological questions.
  9. If Adult Insects Matter, How Much Do Juveniles Matter? helps animal welfare funders to assess the relative value of improvements to the lives of some commercially-important insects.
“Never, in the fifty years in which I have been writing about ethics and animals, have I seen a project as philosophically and empirically daring as [Rethink Priorities’] attempt to develop a method for comparing welfare across species.”
— Peter Singer, moral philosopher

Influence

Thanks in part to our researchers’ outreach, the Moral Weight Project’s findings gained attention among animal advocates and generated discussions within the field at-large.

Impact

The Moral Weight Project is already influencing how funders prioritize their resources.

Animal Charity Evaluators are now integrating elements of the work into their evaluation criteria, with plans to refine their approach in consultation with RP researchers. Broader audiences, such as government agencies in the United States and the Netherlands, are exploring how the research might improve their decision-making.

The Moral Weight Project’s success enabled RP to raise funds for an entire group of researchers to focus on investigating decision-relevant philosophical questions. We invite you to learn more about this Worldview Investigations Team’s work helping donors to make more clear-eyed choices.