Introduction to the Principles of Morals and Legislation

About “Can They Suffer?”

Jeremy Bentham (1748–1832) was a British philosopher and legal theorist best known for laying the groundwork for utilitarianism—the ethical theory that we should do whatever brings the greatest happiness to the greatest number. In his 1780 text Introduction to the Principles of Morals and Legislation, Bentham outlines his radical (for the time) belief that pleasure and pain are the only true measures of what’s morally right or wrong.

But the part that makes a huge splash in the history of animal ethics comes in Chapter XVII, where Bentham pivots to a bold and revolutionary idea: animals deserve moral consideration not because they can talk or reason like us, but because they can suffer. He writes, “The question is not, Can they reason? nor, Can they talk? but, Can they suffer?”

With this single line, Bentham challenges centuries of Western philosophical tradition that placed animals below humans in the moral hierarchy due to their supposed lack of reason or speech. Instead, Bentham argues that the capacity to feel pain and pleasure—sentience—should be the basis for moral concern. In his utilitarian framework, this means that if an animal can suffer, its suffering must count in our moral calculus, just as human suffering does.

Importantly, Bentham isn’t saying animals and humans are equal in every way. He’s pointing out that the relevant moral trait isn’t intelligence or language—it’s the ability to experience harm. This was a groundbreaking move away from more anthropocentric (human-centered) moral theories.

Bentham also critiques the legal systems of his time, noting that laws ignored animal suffering while protecting property rights over living beings. He calls for a shift in how society thinks about animals—not as machines or property, but as sentient beings worthy of moral consideration. This idea would later become foundational to the modern animal rights movement and to utilitarian animal ethics as developed by philosophers like Peter Singer.

In short, Bentham’s insight forces us to reevaluate our moral priorities. If suffering is morally relevant, and if animals can suffer, then we are morally obligated to take their suffering seriously—whether that’s in factory farming, animal testing, entertainment, or any other domain where human interests conflict with animal well-being.

Bentham’s question—Can they suffer?—still echoes today in debates about veganism, animal research, and environmental ethics. It’s a deceptively simple question that upends centuries of human-centered thinking and asks us to broaden our moral community to include the nonhuman world.