Contractarian ethics, while historically excluding animals, has been revised by philosophers who argue that concern for animals is consistent with or required by contractarian principles.
Contractarian ethics presents an interesting philosophical challenge for animal welfare - the framework is built on agreements between rational agents, which animals cannot enter. However, philosophers including Mark Rowlands have demonstrated that the veil of ignorance thought experiment, designed to ensure impartiality, should logically include consideration of animal interests since rational contractors would not know whether they would be born as humans or animals. This revision transforms contractarianism from an obstacle to animal welfare into a potential support. Understanding how different philosophical frameworks can be applied or revised to include animals strengthens the theoretical diversity of welfare advocacy.