Speciesism

The argument against speciesism is often formulated in an abstract way: equal interests should be given equal consideration—regardless of species. A particularly precise and challenging formulation of this idea is the so-called “Name a Trait” argument. It does not claim that humans and animals are identical. Instead, it asks a concrete question: What trait do all humans possess that no farmed animal possesses, which would justify the moral difference that humans must not be eaten, while farmed animals may be?

The strength of the question lies in its structure. It does not deny that there are differences between humans and animals. Of course there are cognitive, linguistic, and cultural differences. The crucial challenge, however, is this: Is there a trait that (1) applies to all humans, (2) applies to no farmed animals, and (3) is morally relevant enough to justify killing and eating one group but not the other?

1. Intelligence

A common answer is: humans are more intelligent. Yet this criterion already fails the universality condition. Not all humans have higher cognitive capacities than all farmed animals. Infants, people with severe cognitive impairments, or individuals with advanced dementia may in some respects fall below certain animals in specific cognitive domains. If intelligence were the decisive criterion, consistency would require excluding such humans from moral protection—an implication most people reject.

Moreover, even if intelligence justifies certain differences in treatment, does it automatically justify killing and eating a being? Intelligence may be relevant for academic achievement—but is it relevant to the basic interest in not being killed?

2. Language Ability

Another frequently cited trait is complex language. Humans possess symbolic, grammatically structured language. However, again, not all humans are capable of language. Infants or people in comas do not lose their moral protection because of this. Language therefore does not appear to be a suitable universal boundary criterion.

3. Moral Agency

Some argue that humans are moral agents—they can understand and follow moral rules—whereas animals cannot. Yet this trait also does not apply to all humans. Infants or individuals with profound intellectual disabilities are not moral agents. Nevertheless, we would not regard them as legitimate sources of food.

Furthermore, moral agency is not the same as moral patiency. A being can be worthy of moral protection even if it cannot itself understand moral duties. We protect humans who cannot bear moral responsibility.

4. Membership in the Human Species

Some ultimately answer explicitly: the relevant trait is simply belonging to the human species, Homo sapiens. But this is precisely where the charge of speciesism arises. Mere biological membership is not an explanatory moral trait—it merely restates the distinction. To say “humans may not be eaten because they are human” does not introduce an independent moral property; it simply appeals to group membership itself.

The “Name a Trait” argument highlights that if species membership alone is sufficient, then one accepts a group-based moral criterion without further justification. Structurally, this resembles other forms of discrimination in which group identity itself is treated as morally decisive.

5. Relationships and Social Bonds

Another argument states that humans stand in special relationships to one another. Family ties, friendship, and social contracts generate obligations. Yet caution is needed here as well. Not every human stands in a close relationship to us—yet we would not eat strangers. Moreover, animals also stand in social relationships, both among themselves and with humans. Relationships may generate special duties, but they do not explain why total instrumentalization outside close bonds would be justified.

6. Potential

Sometimes it is argued that humans possess the potential for higher rationality or moral reflection. Even if this potential is not yet realized in infants, it exists. But the question remains: why should a potential—possibly never realized—ground a stronger right to protection than an actually existing capacity for suffering?

7. The Underlying Moral Criterion

If many of the proposed traits either do not apply to all humans or exist in graded forms among some animals, the question remains: what is the fundamental moral criterion? A common answer is sentience—the capacity to experience suffering and enjoyment. Humans and many farmed animals share this trait.

If suffering is morally bad, it is bad because it is experienced. The species that experiences it does not change the nature of that experience. The “Name a Trait” argument therefore forces one either to identify a consistent, universal, and morally relevant boundary criterion—or to acknowledge that the moral differentiation may rest on an unjustified preference for one’s own group.

Conclusion

The “Name a Trait” argument is not an emotional appeal but a logical challenge. It does not ask, “Are animals the same as humans?” It asks: Which trait justifies the radical moral difference? If no such trait can be identified that satisfies all conditions, then the assumption that species membership alone is a sufficient moral standard begins to waver. The debate then shifts from “Are animals human?” to “Why should belonging to a different species make their suffering morally less relevant?”