An Introduction to Animal Rights Theory: Singer and Regan

The theoretical foundation of the modern animal rights movement rests, to a great extent, on the work of two philosophers. In his best-known book, the Australian philosopher Peter Singer, arguing from a utilitarian standpoint, introduced the concept of "speciesism," criticizing the way humans systematically disregard animal interests on the basis of species alone, and calling for the equal consideration of the interests of all beings capable of suffering.

Regan's Rights-Based Approach

The American philosopher Tom Regan took a different theoretical path. He argued that certain animals, as "subjects-of-a-life," possess inherent value and basic rights independent of their usefulness to humans, and therefore should not be treated merely as tools or resources for human purposes — a position more firm and absolute than utilitarianism's calculus of outcomes.

The Shared Influence of Two Paths

Despite their different theoretical foundations, the ideas of both men have jointly shaped the basic landscape of contemporary animal ethics debate:

• The utilitarian path focuses more on weighing outcomes and the total sum of suffering
• The rights-based path emphasizes more strongly the inviolable status of the individual life
• Both theories raise fundamental ethical challenges to industrial farming
• Contemporary animal protection legislation and advocacy movements are broadly shaped by the intersection of both lines of thought

Understanding these two theoretical threads helps us more clearly distinguish the different philosophical positions and lines of argument behind the everyday question of why we should eat less meat.