Proceedings: Animal Welfare: from Science to Law

Animal Welfare: A Brief History

by Ian J.H. Duncan

Professor Emeritus, Emeritus Chair in Animal Welfare, University of Guelph, Canada

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To cite this article (suggested): Duncan I.J.H., « Animal Welfare: A Brief History » [PDF file], In: Hild S. & Schweitzer L. (Eds), Animal Welfare: From Science to Law, 2019, pp.13-19.


This paper traces the relationship of humankind to animals from the ancient Greeks to the 21st century. Up until the 17th century, philosophers regarded animals as being quite distinct from human beings; human beings had rationality whereas animals had none. This meant that animals had only instrumental value and could be used in any way that human beings desired. During the Enlightenment, philosophers started to realize that the distinction was not clear-cut; animals had some rationality. Bentham (1823) pointed out that rationality was not the important factor; animals could suffer and that was what mattered; animals had intrinsic value. Also during the 19th century, as part of Darwin’s theory of evolution by natural selection, it was seen that states of suffering and states of pleasure could also be adaptive. Although the foundation was now in place, the emergence of modern animal welfare science was delayed through the first 70 years of the 20th century by Behaviorism, which eschewed any consideration of subjective experiences. It took a controversial book by a layperson, Ruth Harrison, to stir both the scientific and philosophical community into developing theories of animal welfare and a book by an ethologist, Donald Griffin, to make it acceptable to study the feelings of animals.

Philosophers and Animal Welfare

A short consideration of the history of how animals have been dealt with by various Western philosophers sets the scene for how they are regarded today. Much of this early history is taken from Preece and Chamberlain (1993) and Preece (2002).

Aristotle (384-322 BC) studied under Plato at the Academy in Athens. Because Aristotle’s ideas were so different from those of Plato, he did not succeed Plato as head of the Academy when Plato died. Instead Aristotle moved to Macedonia for a few years where he educated Alexander (the Great). He then returned to Athens and founded his own academy called the Lyceum. He obviously had an interest in animals since he gave lectures on zoology at the Lyceum. But of course, he is better known for his views on ethics and logic. Aristotle thought that the ability to reason is the highest of all abilities and it is this that sets human beings (actually Greeks!) above all other creatures. Aristotle also introduced the teleological argument i.e. “things being there for a purpose” e.g. “the purpose of rain is to water the plants”. From these two ideas, a great hierarchical structure was built in which those with more reason should control those with less (with Gods being superior to men and controlling them, men being superior to women, Greeks being superior to other races, humans being superior to animals, and so on). According to this structure, human beings had absolute authority over all animals and could do what they liked with them. However, the indifference of the Greeks to the plight of animals pales into insignificance when compared to the attitude of the Romans. The Roman period is infamous for the cruelty to animals (and to human beings) inflicted over 400 years. Hundreds of thousands of animals of a wide range of species were subjected to unspeakable cruelty in the circuses – and all for human entertainment. The decline of the Roman Empire giving way to the Dark Ages is generally mourned as a loss of civilization, but at least the scale of cruelty to animals waned.

There is little in recorded history during the next thousand years detailing how animals were regarded by humankind until Aquinas in the 13th century. Saint Thomas Aquinas (1224-1274) was an Italian Philosopher and a Theologian. He was educated at first at a monastery in Monte Casino, then at Naples, Paris and Cologne. He is best known for his subtle and delicate assimilation of Aristotle’s ideas into the theology of his day. His ideas have experienced short periods of popularity through history. Aquinas rediscovered Aristotle’s writings and he agreed that it was the ability to reason (or rationality) that made human beings distinct from all other animals. However, he gave Aristotle’s ideas a Christian twist. He postulated that animals do not have immortal souls. He also claimed that human beings had no direct obligations to animals. However, they might have indirect moral obligations, in that people who mistreat animals may (1) pick up cruel habits and then treat other human beings badly, and (2) perpetrate a property wrong against the owner of the animal. According to Aquinas, animals do not have moral standing; they only have instrumental value. It is noteworthy that in one respect, Aquinas was correct. Recent research has shown that people who are maliciously cruel to animals early in life are at greater risk of being cruel to people later in life (Boat, 1995; Tallichet and Hensley, 2004; Hensley and Tallichet, 2005).

René Descartes (1596-1650) is often thought of as the father of modern philosophy. He was also a physicist, a physiologist and a mathematician. Descartes is usually singled out for special blame for introducing the idea of animals as ‘automata’ or machines. However, in a more considered review of Descartes’ works, Cottingham (1978) points out that even though Descartes states that animals have no thought or language he does not actually say that they have no feelings or sensations. Indeed Kenny (1970) translates Descartes as saying “Similarly of all the things which dogs, horses and monkeys are made to do, are merely expressions of their fear, their hope, or their joy; and consequently, they can do these things without any thought.” Present-day scholars continue to argue about what Descartes really meant by this. However, he certainly did not treat animals as if they were sentient. He was a vivisectionist, and dissected living, conscious animals (usually dogs) which suggests that he thought that ‘fear’, ‘hope’ and ‘joy’ were in some way unconscious emotions. The concept of ‘unconscious emotion’ is controversial and is currently being debated (e.g. Őhman et al., 2000; Winkielman and Berridge, 2004). Like Aristotle and Aquinas, Descartes also believed that rationality distinguished human beings from other animals and he added that language, which is a unique human attribute (sic), is the only real test of rationality. However, as suggested by the translated passage above, his translators and interpreters may have gone too far in blaming him for ‘animals are machines’. He does seem to allow that animals might have emotions and might be driven by these emotions.

Thomas Hobbes (1588-1679) was an English philosopher who, in 1651, wrote the famous book Leviathan which formed the basis for Western political philosophy. Leviathan concerns the structure of society and legitimate government, and is regarded as one of the earliest and most influential examples of social contract theory. Hobbes’ contention was that human beings act out of self-interest and that this leads to co-operation and social contracts. Since animals have no language (sic), they cannot enter into social contracts with other animals or with human beings. They are therefore not worthy of moral consideration. So, whereas Descartes thought that language was important as a sign of rationality, Hobbes thought that it was necessary for the drawing up of social contracts. However, the end result was the same; animals do not have language, therefore they do not merit moral consideration.

Overlapping with Hobbes was the English philosopher John Locke (1632-1704) who is considered to be the first of the British Empiricists. Empiricism emphasizes the role of experience, particularly sensory perception, in the formation of ideas. Locke postulated that when people are born, their minds are ‘blank slates’ or ‘tabula rasa’. This was contrary to the previous belief that people were born with innate ideas. Locke also developed Thomas Hobbes’ ideas on social contract theory. He was one of the earliest and most influential thinkers of the Enlightenment contributing to political philosophy and liberal theory. His ideas had a big influence on later Enlightenment thinkers such as Voltaire, Jean Jacques Rousseau and David Hume.

It is in Locke’s writings that we get a first glimpse of a change of view with regard to animals. Locke says that there is evidence that animals (or what he calls “brutes”) have the capacity to remember. He also allows that animals seem to have some very simple ideas and they can compare one thing to another – but only very imperfectly. To some extent they can compound (put ideas together) but Locke draws the line at abstraction. He clearly states that animals cannot form abstractions. So Locke concludes that there are huge differences between human beings and other animals, but that animals do have some simple mental capacities, and this is a big departure from calling them ‘automata’.

The German, Immanuel Kant (1724-1804) lived well after Locke but he maintained the traditional view that animals have only instrumental value. Kant is an important philosopher in the development of moral philosophy. He wrote a very influential book called Groundwork of the Metaphysic of Morals. Kant believed that morality is a case of following absolute rules. For example, he thought that lying was morally wrong and that we should never lie no matter what the circumstances are. Kant’s philosophy was that one should treat a human being as an end in himself/herself and not as a means to an end. He developed the philosophy that human beings have intrinsic (or inherent) value and not merely instrumental value. The reason they have intrinsic value (once again) is that they have rationality and in particular they can reason about ethics. Animals, on the other hand, cannot reason (particularly about ethics!), and therefore have only instrumental value.

So these five philosophers, Aristotle, Aquinas, Descartes, Hobbes and Kant, developed a position that has dominated the traditional Western view of how animals should be treated. The position was based on two claims: (1) Human beings have a special attribute that makes them distinct from all other animals (a factual claim) and (2) having this special attribute makes human beings objects of direct moral concern (a moral claim). The special attribute was rationality, and in particular having language and being able to engage in ethical thought. The traditional Christian view incorporated an additional distinction, namely that animals did not have immortal souls. John Locke has been left out of this list because he was the first to realize that the distinction between animals and human beings was not as clear cut as the others suggested.

With the emergence of the period we call ‘The Enlightenment’ in Europe, things started to change. The Scottish philosopher, David Hume (1711-1776), wrote on learning in animals, “It seems evident, that animals learn many things from experience, and infer that the same events will always follow from the same causes”. He went on to say: “Is it not experience, which renders a dog apprehensive of pain, when you menace him, or lift up the whip to beat him?” (Hume, 1739 pp. 397-398). He thus began to dispute the previous views that animals have no moral standing. Hume was a hard-line atheist and so the question of anyone having an immortal soul did not arise.

Jeremy Bentham (1748-1832) was an English social reformer who was very concerned about the conditions that many workers were forced to accept during the Industrial Revolution. He worked closely with James Mill, a like-minded Scottish social reformer. In contrast to Kant, Bentham thought that it was the consequences of actions that were important. So, for example, telling a lie might be morally acceptable if the consequences of doing so were better than not telling a lie. He had little to say about animals. However, in one of his books he dealt very briefly with animals. He rejected both of the previous claims of Aristotle, Aquinas, Descartes, Hobbes and Kant outright. According to Bentham, rationality is not the relevant matter. “The question is not, Can they reason? nor, Can they talk? But, Can they suffer?” (Bentham, 1823). John Stuart Mill (1806-1873) was the son of James Mill and a close friend of Jeremy Bentham. Mill developed Bentham’s ideas into the philosophy of Utilitarianism (Mill, 1910) or The Greatest Happiness Principle according to which “Actions are right in proportion as they tend to promote happiness, wrong as they tend to produce the reverse of happiness”. Happiness is defined as pleasure and the absence of pain; unhappiness is defined as pain and the privation of pleasure. Bentham and Mill did not wish their new theory to have the title “The Greatest Happiness Principle” and they searched around for another name. They came across the word “utilitarian” in the writings of a Scottish novelist, John Galt, and they asked him if they could use this for the name of their theory, and Galt agreed.

Scientists and Animal Welfare

These ideas and theories were those of philosophers. But what about scientists? When did they start to think about animal welfare and, in particular, when did they start to think about sentience? Of course, it could be argued that Descartes was a scientist as well as a philosopher. However, as has already been argued, the evidence shows that Descartes certainly did not treat animals as if they were sentient or as if their welfare mattered.

Most people would probably reach back to the writings of Darwin for some reference to animal sentience. However, more than thirty years before Darwin’s (1872) The Expression of the Emotions in Man and Animals, an English veterinarian was writing about sentience in animals. William Youatt (1776-1847) embarked on a career as a veterinarian at the mature age of thirty-five. He was training to be a minister of the church when he suddenly left home in south-west England and moved to London. He attended the Veterinary College there (later to become the Royal Veterinary College) for two years before leaving and setting up in practice without completing his training. He was a very prolific writer and published several books including Canine Madness (1830) (a book on rabies), The Horse. With a Treatise on Draught (1931), Cattle. Their Breeds, Management and Diseases (1834) and Sheep (1837), many of which are still referred to today. The book that is of particular interest to us is one that deals with many different aspects of animal welfare (Youatt, 1839). In this book Youatt writes of animals’ senses, emotions, consciousness, attention, memory, sagacity, docility, association of ideas, imagination, reason, instinct, social affections, the moral qualities, friendship and loyalty. So he, most definitely, knew that animals were sentient! He wrote of the intellectual faculties “We are endeavouring to shew that the difference [between humans and animals] in one of the most essential of all points, is in degree and not in kind”. He also wrote “We are operating on animals that have, probably, as keen feelings of pleasure and of pain as ourselves”. Youatt condemned many practices as being cruel and inhumane such as, too early training of race horses, steeple-chasing, transport methods for newly-born calves, methods of raising veal calves, slaughter-house management, tail-docking and ear-cropping of dogs, using live bait for fishing, dissection of living animals, and force-feeding of capons and turkeys. It is noteworthy that many of these practices are still being hotly debated today!

In his book The Expression of the Emotions in Man and Animals Darwin (1872) noted the universal nature of human facial emotional expression, described some commonalities in expression of emotions in animals, and suggested a shared evolution. Darwin was mainly interested in emotional expression and so he described the underlying anatomy and physiology, the signal value of the expression, and the evolution of the emotions. He seemed to accept the subjective experience associated with the emotions, but this was not explored in any depth. It was left to George John Romanes (1848-1894), a friend and disciple of Darwin’s, to be explicit about the subjective experiences of feelings. In his book Mental Evolution in Animals, Romanes (1883) wrote “Pleasures and Pains must have been evolved as the subjective accompaniment of processes which are respectively beneficial or injurious to the organism, and so evolved for the purpose or to the end that the organism should seek the one and shun the other.

The 100-year Hiatus

Since it was accepted 130 years ago by philosophers, scientists and society in general that animals have feelings, why did it take another 100 years for animal welfare science to develop as an accepted discipline? The answer seems to be that Behaviorism emerged at the start of the 20th century and had a huge inhibiting effect on the study of subjective phenomena. Behaviorism is a branch of psychology that was developed in the USA during the first 70 years of the 20th century. The foundations were laid by William James (1842-1910) who, late in his career, wrote “Consciousness … is the name of a non-entity, and has no right to a place among first principles. Those who still cling to it are clinging to a mere echo, the faint rumour left behind by the disappearing ‘soul’ upon the air of philosophy… It seems to me that the hour is ripe for it to be openly and universally discarded” (James, 1904).

The father of Behaviorism is usually considered to be J.B. Watson (1878-1958). He laid out the principles of the discipline and wrote, “The behaviorist sweeps aside all medieval conceptions. He drops from his scientific vocabulary all subjective terms such as sensation, perception, image, desire and even thinking and emotion” (Watson, 1928).

The psychologist who developed techniques for measuring behaviour objectively according to behaviourist rules was B.F. Skinner (1904-1990). He is best known for inventing the operant conditioning chamber or ‘Skinner Box’. He stated, “We seem to have a kind of inside information about our behaviour – we have feelings about it. And what a diversion they have proved to be! … Feelings have proved to be one of the most fascinating attractions along the path of dalliance” (Skinner, 1975).

The Behaviorists were important scientists and their influence was felt throughout the animal behaviour field including in the discipline of ethology which was developing rapidly in Europe. With very few exceptions, behavioural scientists eschewed any consideration of animals’ subjective experiences. There is no doubt that this delayed the emergence of animal welfare science by 80-100 years.

A Re-awakening

Big changes took place in animal agriculture following the Second World War. In response to the huge demand for cheap food there was a rapid industrialization of production methods. It seems likely that the general public was not aware of these changes since they often took place in closed housing systems. When the more intensive methods were revealed and criticized by Ruth Harrison in her book Animal Machines (Harrison, 1964), there was a huge public outcry. Harrison criticized intensive broiler production methods, poultry slaughter houses, battery cages for laying hens, crates for white veal production, broiler beef production, intensive rabbit production and ‘sweat-box’ conditions for fattening pigs. In her criticisms, Harrison laid much emphasis on animal suffering, that is, on the negative subjective states that the animals were experiencing. The public condemnation was so great that the British Government felt obliged to form a Committee of Enquiry under the chairmanship of Professor Rogers Brambell. Their report, often called the ‘Brambell Report’ (Command Paper 2836, 1965) concluded that, indeed, there was some cause for concern about animals in intensive production systems but that, in many instances, there was a lack of good scientific evidence to draw firm conclusions. They also thought that feelings were an important feature of welfare. They stated, “Welfare is a wide term that embraces both the physical and mental well-being of the animal. Any attempt to evaluate welfare, therefore, must take into account the scientific evidence available concerning the feelings of animals that can be derived from their structure and functions and also from their behaviour” (Command Paper 2836, 1965).

Nevertheless, in spite of these allusions to the feelings of animals in general and the suffering of animals in particular, the widespread view amongst the scientific community at this time was that welfare was intimately connected with stress. This can be seen in the publications of this period as scientists struggled to investigate welfare (e.g. Bareham, 1972; Bryant, 1972; Wood-Gush et al., 1975).

This pattern was broken by an American ethologist, Donald Griffin, who wrote a book entitled The Question of Animal Awareness (Griffin, 1976). He himself was not particularly interested in animal welfare, but his ideas legitimized a consideration of animals’ subjective experiences and suddenly new approaches became available to animal welfare scientists. Thereafter, there was a burgeoning literature on animal sentience and welfare (e.g. Dawkins, 1980; Duncan, 1981, 1993; Appleby et al., 2011).

In parallel with the scientific re-awakening of interest in sentience and animal welfare, there has been an intense focus on the ethics of animal use. This was probably started by Peter Singer (b1946), an Australian philosopher who now holds the Chair of Bioethics at Princeton University. He has vigorously promoted a utilitarian approach to animal welfare. He published Animal Liberation in 1975 with a 2nd edition in 1990 and a 3rd edition in 2002. This was (and is) a very influential book. Singer argues that most animal use (including animal agriculture) is deeply objectionable. So he is arguing about the facts. He says that he is not against using animals or even against killing them, if (and only if) they have a good quality life and a painless death. Interestingly, Singer is also regarded as the father of Animal Rights although he himself is most definitely a utilitarian. A utilitarian approach has proved to be very useful in dealing with various moral dilemmas in human affairs. However, when animals are involved, it often becomes extremely difficult to weigh the happiness of humans against the suffering of animals. For example, should a scientist carry out medical research on chimpanzees in which many of the chimps will suffer and die but the research may find a cure for AIDS which will reduce suffering and benefit millions of human beings?

Using much of the evidence produced by Singer in Animal Liberation, Tom Regan (1938-2017), Emeritus Professor of Philosophy at North Carolina State University, developed the philosophy of Animal Rights and in 1983 published The Case for Animal Rights. In this book he argues that we are all subject of a life, conscious beings, have an individual welfare, want and prefer things, and believe and feel things. Therefore we (and all sentient creatures) have inherent value. Regan builds his argument as follows, “Individuals who have inherent value have an equal right to be treated with respect… It follows that we must never harm individuals who have inherent value” (Regan, 1983). According to Regan, killing is the biggest harm we can do to another individual. Regan is an abolitionist. He believes that human beings should not use animals at all – in animal agriculture, in biomedical science, for work or sport, or even as companions. It should be pointed out that Regan’s version of animal rights is extreme; it is possible to build theories of limited animal rights (Tannenbaum, 1995). Such a theory might assign rights such as: farm animals have a right to be protected from climatic extremes; laboratory animals have a right to express strongly motivated behaviour; companion animals have a right to daily exercise; and so on.

One of the problems with Complete Animal Rights is that it only deals with human use of animals. However, many human activities are more indirect; the pollution of rivers, lakes and oceans, the pollution of the atmosphere, global warming etc., can all have a profound effect on the welfare of animals. Even activities like building roads, laying pipelines, and growing crops can have adverse effects on welfare. How can these indirect effects of human activities be studied properly if we are constrained by the philosophy “Do not use animals”?


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