This article reviews the law and literature concerning the way that we look at rights issues and the foundational principles that are asserted to be the predicates of rights in our legal system. Particular attention is paid to problems surrounding the possible extension of legal rights to animals. The analysis reveals that while there are many ways of thinking about and grounding rights, most theorists insist on asserting that there is some single principle or concept that is the foundation for the granting of legal rights. It is argued here that this obsessive search for a single explanation for legal rights is folly. Instead, rights should be seen as having composite foundations formed from many moral, policy, social and cultural supports. It is further asserted that among the many things that should have significance in determining whether an entity, human or non-human, is a rightholder is one that is almost universally ignored in animal rights and other rights literature: emotions, and in particular, compassion. Emotions, being essential aspects of our nature and of our moral lives, are of relevance in determining who should be rightholders. If applied to the issue of granting rights to animals, our sense of compassion should count as a reason for granting rights to animals.