Speciesism is a term used in philosophy to describe how people treat individuals from different species. It has different meanings. Some say it is unfair treatment based on a person's species, while others say it is treating different species differently without considering if it is fair. Richard D. Ryder, who created the term, described it as "a bias that favors the interests of people from one's own species over those of other species." Speciesism leads to the belief that humans can use non-human animals in harmful ways, which is common in today's society. Studies from 2015 and 2019 show that people who support using animals for human purposes often also hold other unfair beliefs, like racism or sexism, which help justify systems of inequality.
The word "speciesism" was first used in 1970 during a protest against experiments on animals. Philosophers and animal rights activists say speciesism is part of industries that use animals, such as factory farming, killing animals for food, blood sports (like bullfighting and cockfighting), taking animal fur or skin, testing on animals, and not helping animals in nature who are suffering. It also includes labeling some animals as "alien" or "invasive," which gives people a reason to kill them.
Important supporters of the idea include Peter Singer, Oscar Horta, Steven M. Wise, Gary L. Francione, Melanie Joy, David Nibert, Steven Best, and Ingrid Newkirk. Scholars have debated the ethics and meaning of speciesism. Some, like Carl Cohen, Nel Noddings, Bernard Williams, Peter Staudenmaier, Christopher Grau, Douglas Maclean, Roger Scruton, Thomas Wells, and Robert Nozick, have criticized the term or parts of it.
History
French naturalist Georges-Louis Leclerc, Comte de Buffon, wrote in Histoire Naturelle in 1753 that animals with body structures similar to humans likely feel sensations similar to humans. He also believed these sensations depend on the strength of their senses. However, Buffon also believed a difference exists between humans and other animals.
In his poem Poème sur le désastre de Lisbonne, French writer Voltaire wrote that all living beings, humans and animals alike, are subject to the same natural laws and experience pain and death.
Jeremy Bentham, an early Western philosopher, argued that all beings capable of suffering should be treated with equal moral consideration, regardless of species. In his 1789 book An Introduction to the Principles of Morals and Legislation, he stated that species membership does not determine moral worth. Bentham also supported laws to protect animals from unnecessary harm, though he accepted the use of animals for human purposes if cruelty was avoided.
In his 1824 work Moral Inquiries on the Situation of Man and of Brutes, English writer Lewis Gompertz argued that humans and animals share similar emotions, such as hunger, fear, and anger. He noted that humans and animals also have similar physical traits and suggested this shows a connection in their ability to feel. Gompertz criticized the way humans use animals, saying people often ignore their needs and feelings.
In 1838, naturalist Charles Darwin wrote in his notebook that humans are not unique creations of a deity but evolved from animals. In his 1871 book The Descent of Man, Darwin argued that humans and animals share a common ancestry and that human traits evolved gradually over time.
In 1843, Lewis H. Morgan wrote an article titled Mind or Instinct: An Inquiry Concerning the Manifestation of Mind by the Lower Orders of Animals, in which he described examples of animals showing memory, planning, and reasoning. He argued that animals and humans share a similar mental ability, differing only in strength. Morgan rejected the idea that animal behavior is driven by instinct alone and criticized practices like hunting for sport. He also suggested that animals might have moral abilities and souls, placing species on a scale of intelligence while believing in creationism.
German philosopher Arthur Schopenhauer criticized the belief that humans are superior to other animals, calling it a flaw in Christianity and Judaism. He praised Brahmanism and Buddhism for teaching that humans and animals are connected and should be treated with respect.
According to historian Chien-Hui Li, some secular thinkers in the late 19th and early 20th centuries argued that animals should be treated with moral consideration based on their ability to feel pain and their shared evolutionary history with humans. These thinkers rejected religious ideas that separate humans from animals and instead used scientific theories to support animal rights and welfare.
In his 1892 book Animals' Rights, British writer Henry S. Salt argued that humans should not see a "great gulf" between themselves and other animals but instead recognize a shared "universal brotherhood" of all living beings.
In his 1897 work Evolutional Ethics and Animal Psychology, American scholar Edward Payson Evans criticized the idea that humans are fundamentally different from other animals. He argued that Darwin’s theory of evolution shows humans have moral duties not only toward enslaved people but also toward nonhuman animals. Evans believed animals need legal protections to prevent cruelty and that recognizing the kinship between humans and animals makes mistreatment of animals impossible.
An 1898 article in The Zoophilist, titled Anthropocentric Ethics, noted that some early civilizations, before Christianity, saw kindness to animals as a moral duty. It mentioned figures like Zarathustra, Buddha, and early Greek philosophers who practiced vegetarianism. The article said this idea of human-animal kinship was present in early Christianity but later challenged by figures like Origen, who saw animals as tools for humans. It concluded that the connection between animal behavior and ethics was gaining attention.
In 1895, American zoologist and philosopher J. Howard Moore argued that vegetarianism is the ethical choice based on the shared evolutionary history of all living beings. He criticized the idea that animals were created for human use and proposed "zoocentricism," a moral system that includes all sentient beings. In his 1906 book The Universal Kinship, Moore compared mistreating animals to denying ethical relationships among humans and urged people to apply the Golden Rule to all sentient beings.
The term "speciesism," describing prejudice based on species membership, was first used in 1970 by British psychologist Richard D. Ryder in a privately printed pamphlet. Ryder was part of a group of academics in Oxford, England, who later became known as the Oxford Group, a key early group in the animal rights movement.
Social psychology and relationship with other prejudices
Scholars such as philosopher Peter Singer and botanist Brent Mishler have argued that speciesism is similar to racism, which is the belief that some human races are superior to others.
In the 2019 book Why We Love and Exploit Animals, Kristof Dhont, Gordon Hodson, Ana C. Leite, and Alina Salmen explain the psychological links between speciesism and other prejudices, such as racism and sexism. Marjetka Golež Kaučič connects racism and speciesism, stating that discrimination based on race and species is closely related. Human rights laws are the legal basis for developing animal rights, Kaučič explains. She also notes that racism and speciesism are connected to issues of freedom, both for groups and individuals.
In one study, 242 participants answered questions on the Speciesism Scale. Those who scored higher on this scale also scored higher on scales measuring racism, sexism, and homophobia. Other studies show that people who support animal use often also support racist and sexist views. These beliefs help justify systems of inequality and power. Researchers suggest these connections are tied to the idea of social dominance.
Psychologists have studied speciesism as a specific attitude, using a Likert scale to measure it. Studies show speciesism is a consistent trait that varies between individuals and is linked to other factors. For example, speciesism has weak links with homophobia and right-wing authoritarianism, and stronger links with political conservatism, racism, and system justification. It also has moderate links with social dominance orientation and sexism. Social dominance orientation is thought to explain much of these connections. When this factor is considered, many links become weaker or disappear. Speciesism also affects how people act toward animals and their food choices.
People who argue that speciesism is unfair often mention mammals and chickens in research or farming. However, there is no clear agreement among activists about which nonhuman species should be treated equally to humans or given extra protection. This includes mammals, birds, reptiles, insects, and bacteria. A study by Miralles et al. (2019) found that humans feel more empathy for organisms that are evolutionarily closer to them. The more distant an organism is from humans, the less people recognize their similarities and the less they care about their well-being.
Some researchers suggest that speciesism, like other prejudices, is a negative attitude toward a group. Studies show that people often think speciesists share similar traits with racists, sexists, or homophobes. However, it is unclear if speciesism is linked to other types of prejudice, such as negative views of overweight people or Christians.
Psychological studies also show that people value some species more than others, even when intelligence and awareness are considered. One study found that children have less speciesist views than adults, suggesting that speciesist beliefs are shaped by society over time.
Relationship with the animal–industrial complex
Piers Beirne says speciesism is the main idea behind the connected systems of the animal–industrial complex, which includes factory farms, experiments on animals, hunting, fishing, zoos, aquariums, and the trade of wild animals. Amy Fitzgerald and Nik Taylor explain that the animal-industrial complex both causes and results from speciesism, which they compare to racism or sexism. They also say that hiding the fact that meat comes from animals is an important part of the animal–industrial complex under capitalist and neoliberal systems. Speciesism leads to the belief that humans can use non-human animals, a common idea in modern society.
Sociologist David Nibert writes that some scholars believe all forms of animal farming are based on speciesism, treating animals as only economic tools. The animal–industrial complex, which depends on raising and killing animals, is seen as the physical form of speciesism, with speciesism acting as a type of production system. In his 2011 book Critical Theory and Animal Liberation, J. Sanbonmatsu argues that speciesism is not a lack of morals toward animals but a system of production and material processes connected to capitalism.
Arguments in favor
Philosopher Carl Cohen stated in 1986: "Speciesism is not just a possible idea; it is necessary for making the right decisions, because those who do not recognize important moral differences between species are likely to misunderstand their true responsibilities." Cohen explains that racism and sexism are wrong because there are no meaningful differences between races or sexes. However, he argues that significant differences exist between humans and animals. He believes animals do not qualify for Kantian personhood, which is a type of moral status that Kant believed was unique to humans, and therefore, animals do not have rights.
Nel Noddings, an American feminist, criticized Peter Singer’s concept of speciesism for being too simple and for not considering the context of species preference, as racism and sexism have considered the context of discrimination against humans. Peter Staudenmaier argued that comparing speciesism to racism or sexism makes the comparison less important.
A similar argument was made by Bernard Williams, who noted that racists and sexists ignore input from people of different races or sexes when deciding how they should be treated. In contrast, Williams explained that humans are the only ones who can discuss how animals should be treated. He also pointed out that being human is often used as a reason to oppose discrimination based on race or sex, but racism and sexism are rarely used to argue against discrimination.
Williams supported speciesism, which he called "humanism," by asking, "Why are traits like personhood considered important when deciding whether to destroy certain animals, but being human is not considered important when deciding how humans should be treated?" He argued that claiming humans are valuable because they are human does not weaken speciesism, as humans also value themselves. Williams suggested that the only way to resolve this issue would be to argue that certain traits are "better," but this would require justifying why they are better, which might depend on human preferences.
Christopher Grau agreed with Williams, stating that using traits like rationality, sentience, or moral agency to determine moral status would require proving why these traits are more important than others. He argued that no special status can be given to these traits unless an impartial observer exists to declare them so. Grau also noted that even if such an observer existed, it might still support speciesism, as humans could have reasons to care about humanity. He added that if an impartial observer valued reducing suffering above all else, it might prefer ending humanity to stop suffering, which would not oppose speciesism.
Douglas Maclean agreed that Singer raised important questions, especially his argument about "marginal cases," which refers to animals that are similar to humans in some ways. However, Maclean questioned whether human morality can apply to animals, noting that people usually try to stop harm to humans but accept similar actions by animals. He suggested that morality makes sense only in human relationships and becomes less applicable as one moves away from humans.
Roger Scruton, a British philosopher, called the rise of the animal rights and anti-speciesism movement "the strangest cultural shift within the liberal worldview." He argued that rights and responsibilities are unique to humans and do not apply to animals. He claimed that if animals had rights, they would also have duties, which they would break, such as by killing other animals. He criticized anti-speciesism advocates for using "pre-scientific" anthropomorphism, or attributing human-like traits to animals, which he compared to a fantasy world.
Thomas Wells argued that Singer’s focus on ending animal suffering could justify killing all animals to prevent their suffering, as they could no longer feel pain. He also noted that Singer ignores suffering caused by animals themselves or by nature, creating a hierarchy of suffering that contradicts his claim of equality. Wells pointed out that Singer uses the ability to suffer as a standard for moral status but denies it to plants, even though they react to stimuli. He questioned whether nonhuman animals feel pain in the same way humans do.
Robert Nozick argued that if species membership is not important, then endangered animals would have no special claim to protection.
The Rev. John Tuohey, founder of the Providence Center for Health Care Ethics, wrote that the logic behind anti-speciesism is flawed. He noted that while the animal rights movement has influenced efforts to reduce animal experimentation in the United States, no one has provided a strong argument for treating all species equally.
Arguments against
Paola Cavalieri explains that the current humanist idea is that only humans are part of the moral community and should all receive equal protection. She says that being part of a species automatically means having moral rights. This idea includes all humans being protected equally but excludes nonhumans from this protection.
In many societies, nonhumans have some moral rights, but these rights usually only protect them from unnecessary harm, which Cavalieri calls "wanton cruelty." Anti-speciesists argue that it is unfair to give moral rights to all humans, no matter their abilities, but deny these rights to nonhumans, even if some nonhumans have abilities similar to humans. They use the "argument from marginal cases" to say that if people who are very young, very old, disabled, or in a coma have moral rights, then nonhuman animals should have those rights too, since nonhumans do not have abilities that humans lack.
Steven M. Wise, an American legal scholar, says speciesism—favoring humans over nonhumans—is as unfair as other forms of bias. He references R.G. Frey, who wrote in 1983 that if forced to choose between stopping animal experiments or allowing experiments on people with limited abilities, he would choose the latter. Frey said this is not because he believes humans are more valuable, but because he cannot think of any reason to value human life more than animal life.
Richard Dawkins, an evolutionary biologist, wrote against speciesism in several books, explaining how it connects to evolutionary theory. He compared past racist ideas to modern speciesist ideas. In The Blind Watchmaker, he said that the extinction of species with traits between others helps clarify both science and human ethics. Dawkins also said that humans often divide the world into categories based on language, not biology, and that animals are grouped into species in the same way.
In 2007, Dawkins told a group that eating meat is similar to how many people once supported slavery, even if they felt it was wrong. He said people often act against their beliefs because of economic or social reasons.
"Libertarian extension" is the idea that the value of nature should include non-living things like trees, plants, and rocks, not just living beings. Ryder disagrees, saying that value only exists if something is conscious or could become conscious. He argues that rocks, rivers, and buildings have no interests or rights of their own, even though they may be valuable to humans or other living beings.
David Sztybel wrote in 2006 that the racism of the Nazis is similar to the speciesism in eating meat or using animal products from factory farms. Y. Michael Barilan, a doctor, says speciesism is not the same as Nazi racism because the Nazis supported those who harmed others and punished the weak. He describes speciesism as giving rights based on group membership, not just moral reasons.
Law and policy
The first major law in the United States that protected animals was called "An Act for the More Effectual Prevention of Cruelty to Animals." It was passed in 1867. This law allowed people to take action against those who harmed animals. Over time, the law was updated to fit modern needs in each state. Originally, it covered issues like not taking care of animals, leaving them alone, hurting them, using them in fights, transporting them, and setting standards for animal shelters and licenses. Although people had started caring about animals as early as the late 1800s, new laws were created around the same time that Richard Ryder introduced the idea of speciesism, which is the belief that humans are more important than other animals. In the United States, new laws were passed to improve how animals were treated in farming, research, and other industries. For example, the Humane Slaughter Act, passed in 1958, aimed to reduce the suffering of animals during slaughter. Later, the Animal Welfare Act of 1966, created by the 89th United States Congress and signed by President Lyndon B. Johnson, set stricter rules for how animals were treated in laboratories and public displays. This law has been changed and expanded since it was first passed. These early laws helped change how people thought about the rights of nonhuman animals, which Richard D. Ryder and Peter Singer would later discuss in the 1970s and 1980s.
Great ape personhood is the idea that great apes, like chimpanzees and gorillas, have qualities such as intelligence and awareness that should be recognized by the law. Instead of only protecting them under animal cruelty laws, they should be seen as individuals with rights. Giving personhood to nonhuman primates would mean that their personal needs and interests must be considered in legal decisions.
Observances
The World Day for the End of Speciesism (WoDES) is an international event that works to oppose speciesism. It is held every year at the end of August since 2015. This event was started in 2015 by members of the Swiss group Pour l'Egalité Animale (PEA). This group manages the event each year and offers help to support it.
The "World Day Against Speciesism" is celebrated every year on June 5.