Peter is often called “world’s most influential living philosopher” due to his work on the ethics of our treatment of animals, and he is often credited with starting the modern animal rights movement with his book "Animal Liberation." Peter's writing has also influenced the development of the global effective altruism movement, which inspires people to give back as effectively as they can. You can learn more about Peter at petersinger.info and about Effective Altruism at effectivealtruism.org.