At the core of animal liberation ethics is an argument of consistency directed against the contemporary view of equality. 

This view claims that all human beings are equal regardless of their gender, race, or psychological traits, such as intelligence, skills, and sensitivity. It rejects the view that members of a particular biological group may be discriminated against because they belong to that group, and it is morally offensive to the notion that less talented, disabled, young children, or elderly people may be routinely exploited by more rational or independent humans. Thus, neither the biological nor the special psychological characteristics above the sensation are important for equal treatment. If we are morally required to treat like states equally, as moralists have urged since Aristotle, then the moral status of members of other species must be the same as the moral status of members of our species on a similar psychological level. This means giving the most basic rights to the individual animals that humans use as means to achieve their ends.

The ethics of animal liberation, which became important in the 1970s, were seen as subversive to theory and accepted practice. In response to its challenge, defenders of humanism – the view that human lives and interests must always be given more weight than non-human lives and interests – have made a number of objections. They claimed that humans have special duties towards their closest relatives. The differences between species, unlike race, correspond to large differences; That rights cannot be enjoyed without the ability to claim them; That no rights can be enjoyed without the ability to assume duties; And even non-human animals, which lack verbal language, do not have conscious interests that must be taken into account. Such objections can be dismissed. First of all, the idea of ​​kin can be used to justify discrimination against members of the human race as well as members of other species. Even if race does not correspond to significant differences, gender does. We also grant basic rights to young children, although they certainly cannot claim them or have duties. Finally, the theory of evolution eliminated the traditional concept of fixed and completely distinct gems; Since Darwin, the idea of ​​differences in species rather than degree between us and all other animals has been improbable. Even the (controversial) appeal of the possibility of becoming full-fledged rational beings in order to draw a line between infants and non-human animals at a similar mental level ignores the fact that there are humans whose mental disabilities cannot be reversed.

All things considered, those who argue against species theory believe that there is no argument for distinguishing between members of different species that cannot be used as an argument for distinguishing between humans. The justifications for equality can only be accepted to a certain extent and then are arbitrarily rejected. In highlighting the arbitrariness of the human situation, the ethics of animal liberation not only seeks to protect non-human beings but also challenges the direction and foundation of much Western moral reasoning.

From this perspective, the demand to remove other animals from the world of things for their incorporation into our moral community, and the goal of dismantling social institutions and practices that are based on their exploitation for human ends, are integral. From that slow but steady process of granting the right to vote, which has so far been characterized by what we call moral progress.