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Animal Research: I. Historical Aspects


The historical background of the discussion of the ethics of animal experimentation will be examined by considering first the rise of medical research (physiology and pharmacology particularly), then the emergence and consolidation of opposition to research using live animals. Both developments were shaped, of course, by the capabilities and goals of science in every era, and were also powerfully influenced by the philosophical and religious environments within which science operated.

The History of Animal Experimentation

Vivisection—the cutting open of living animals to observe their inner structure and functioning—can be traced to Greek antiquity, but it was Galen (129–c. 210 c.e.), the most celebrated physician of the Roman Empire, who developed vivisection as a tool for methodical physiological investigation. By such procedures as ligation of the ureters to show they channeled urine from the kidneys to the bladder, and sectioning of the spinal cord at different levels to establish the relations between individual nerves and the body regions they served, Galen demonstrated the power of surgical interventions to produce a deeper understanding of bodily functions (Rupke).

During the early medieval period, animal experimentation fell into the same desuetude as other areas of scientific inquiry. To be sure, ancient scientific traditions were preserved and elaborated upon by Arabic scholars, but not until the late Middle Ages did an experimental spirit revive in the European world. Skepticism about the adequacy of ancient scientific ideas built to a head during the 1500s, culminating for the life sciences in the 1543 publication of De Humani Corporis Fabrica by Andreas Vesalius (1514–1564). The first anatomy text based on careful dissection of the human body, Vesalius's work sharply revised the long-accepted anatomical system of Galen (which had been derived entirely from animal dissections), and thus encouraged experimental reevaluation of Galenic theories of physiology as well.

The most significant correction of Galen's physiology was accomplished by the English physician William Harvey (1578–1657), whose demonstration of the circulatory movement of the blood through the body was based on observations of the contractions of the heart, ligation of the aorta and vena cava, and other vivisection procedures performed on more than eighty species. Harvey's De Motu Cordis (1628) heightened misgivings about the validity of other Galenic ideas and confirmed animal experimentation as an invaluable technique for physiological discovery. Vivisection became a commonplace scientific activity by the later 1600s; it was used over the next century and a half to investigate such varied phenomena as respiration, pancreatic secretion, and blood pressure (Rupke; Foster).

Yet as late as 1800, experimentation was still only one of several approaches to elucidating physiological processes. Drawing conclusions about function on the basis of structure—deducing physiology from anatomy—remained popular, as did a priori theorizing in accord with some physical or chemical model; experimentation might be employed in either of those cases, but only to substantiate the preestablished theory. That overly rationalistic orientation to physiology and medicine was already coming under attack, however, by the philosophe-physicians of the "Paris School." Their call for a medicine rooted in empiricism was answered most eagerly and effectively by Francois Magendie (1783–1855), who from 1805 through the 1820s used animal experimentation to clarify such questions as the mode of action of strychnine, the mechanism of emesis, and the functioning of the nervous system. Magendie insisted on analyzing function without being prejudiced by anatomical structure, and thereby established irrevocably the superiority of the experimental method for physiological inquiry. (Contemporaneously, researchers at French veterinary schools were also developing physiology along experimental instead of speculative lines). Magendie's pupil, Claude Bernard (1813–1878), utilized the experimental method even more successfully, discovering the vasomotor nerves, the glycogenic activity of the liver, the digestive role of pancreatic juice, and the mechanism of curare's effects on neuromuscular function. Bernard was equally significant for the philosophical analysis of the necessity of animal experimentation presented in his Introduction a l'etude de la medecine experimentale(1865). There he argued that it was unethical to experiment on human beings, no matter how beneficial the findings might prove for others, if the experiment could harm the subject to any extent whatever. Benefit to others did, on the other hand, justify experiments, including painful ones, on animals. The fact that many human lives could be saved by a relatively few animal deaths made the practice of vivisection a "right," he concluded, "entirely and absolutely" (p. 178). Bernard's analysis solidified the recognition of experimental research with animals as an essential practice for medical progress (Lesch; Rupke; Schiller).

At the same time, physiology and other experimental medical sciences were achieving the status of distinct, institutionalized professions. Historically, physiology had been pursued by physicians in whatever time they had left from treating patients or giving university lectures (and also, on occasion, by amateurs of means). The French had taken the lead in making physiology an independent discipline, yet it was in Germany that research physiology bloomed as a new professional field. The nineteenth-century reformation of universities in the German states, with its emphasis on research and the uncovering of new knowledge, led to the establishment of research institutes employing full-time physiologists, along with pharmacologists and other biological experimenters (Coleman and Holmes). The expectation that research would result in practical medical applications useful to humankind attracted both political and philanthropic support, and ultimately expectation was fulfilled with the flowering of medical microbiology and immunology in the 1880s. The germ theory was built upon laboratory experiments on thousands of animals; applications of the theory quickly made surgery far more effective and safe, and sharply refined programs for the prevention of epidemic disease. Louis Pasteur (1822–1895) discovered a vaccine for rabies in 1885 by infecting numerous dogs and rabbits with the disease, while the research leading to the introduction of diphtheria antitoxin in 1891 involved injecting guinea pigs, rats, and other species with diphtheria toxin. Such breakthroughs allowed experimental medicine to grow by feeding on itself, discovery generating support for more laboratories and scientists, leading to further discovery. By 1900, the German research ethos had established itself throughout the Western hemisphere, even in the United States (Fye). During the course of the twentieth century, moreover, the use of animals in research spread beyond the boundaries of physiology and pharmacology into areas such as psychology, the standardization of drug products, and toxicity testing of cosmetics and other consumer products. The "laboratory animal" has become a universal tool and symbol of medical progress and modern civilization.

The History of Opposition to Animal Experimentation

The laboratory animal also became, in the later years of the twentieth century, the chief object of attention of an aggressive animal rights movement (Plous). The movement's concentration on the immorality of animal experimentation seems odd on first consideration, since medical research, unlike other uses of animals as means to human ends (for food, clothing, sport, entertainment), has yielded unquestionable and inestimable benefits, and for animals as well as people. When examined historically, however, the focus on medical research becomes understandable, as it was the development of vivisection that most forcefully raised the question, "Do animals deserve the same moral consideration as humans?"

Initially, the answer was no. The rapid expansion of animal experimentation during the 1600s did provoke objections, but complaints were the exception, and were usually an experimenter's personal expression of revulsion rather than the product of a moral philosophy condemning cruel treatment of animals (anesthetics were not introduced into surgery, or research, until the mid-1800s). The absence of significant opposition to animal experimentation in the seventeenth century has often been attributed to the influence of the French philosopher and speculative physiologist René Descartes (1596–1650), who believed animals to be insensitive automata. Yet most experimenters recognized that animals did indeed feel pain; they simply did not regard the infliction of pain in experiments as cruelty. Physiologists accepted, with the rest of society, that humankind had been given dominion over animals to use as they saw fit. As scientists, furthermore, they considered experimentation the noblest of uses, since the unveiling of nature's design was a moral duty whose fulfillment deepened understanding of the Creator (Guerrini; Ritvo; Rupke). Animal research continues to the present to be justified on those two grounds, that it is a practical good—it benefits people; and an intellectual good—it enlarges understanding of the natural world.

Those justifications came under attack with increasing frequency during the second half of the eighteenth century. The humanitarian turn of mind engendered by the philosophical and religious emphases of the Enlightenment included a greatly heightened sensitivity to suffering that was readily extended beyond fellow humans to the higher animals. William Hogarth's print "The Four Stages of Cruelty" (1750–1751), for example, depicted the barbarous treatment of dogs and cats as the first stage of descent into savagery. The revolutionary's declaration of liberty, equality, and fraternity could likewise be interpreted as applicable to the animal creation. To be sure, the great majority of philosophers believed the exercise of natural rights required rational thought and speech, and thus could be granted only to humans. The Enlightenment's abhorrence of pain, however, made sentience a primary consideration for some thinkers. Jeremy Bentham (1748–1832) argued that animals' ability to feel and suffer earned them entrance to the sphere of moral consideration; less well-known writers even insisted that kind handling was a "right" to which animals were entitled. And although the most common criticisms of abuse were directed at the use of animals for food, labor, and sport, explicit attention was occasionally given to experimentation. Samuel Johnson (1709–1784), for one, not only denied that any practical benefits had come from animal research, he maintained that even if there had been a payoff, the gain was ill-gotten, tainted by the torture of innocent creatures. He repudiated obtaining knowledge through torment, in fact, as ultimately hurtful to society as well, for the callous treatment of animals would harden experimenters' hearts toward human suffering. Through assertions of the inutility, immorality, and corrupting influence of experimentation, philosophical argument overtook empathy as the basis of opposition to animal research (Passmore; Stevenson).

Philosophical argument matured into political action during the nineteenth century, hardening that triad of objections into the spearhead of an organized antivivisectionist movement. At first, the protesting of vivisection lacked an independent identity; rather it was subsumed under the broader animal welfare movement, largely because the country where animal protectionist sentiment was strongest—England—was the country where experimental physiology was weakest. Despite Harvey's example of two centuries earlier, English physiologists had come to rely primarily on dissection and anatomical reasoning rather than vivisection. There was too little animal experimentation at home to necessitate a distinct campaign; it seemed sufficient to fire occasional shells at less civilized scientists across the Channel.

By the 1850s, however, English physiologists realized that they had fallen behind their continental counterparts, and that animal experimentation was the key to catching up. Since ether and chloroform had been introduced as anesthetics in the 1840s, vivisection was far less harrowing, and it soon became as common in England as in Europe. Medical experimentation involved any number of species, but dogs and cats were especially common, and since the keeping of domestic pets had assumed an almost sacred place in genteel British culture during the first half of the century, vivisection could be horrifying even with anesthesia. (And not all researchers employed anesthetics, as the drugs sometimes interfered with the experiment.) Animal protectionists could thus still equate vivisection with cruelty, and this invasion of British soil by scientific barbarism incited a counterattack. The redoubtable Frances Power Cobbe (1822–1904) assumed generalship of the antivivisection forces, mobilizing them in 1875 into The Society for the Protection of Animals Liable to Vivisection—the first organization dedicated to overthrowing animal experimentation. Parliament, meanwhile, had appointed a Royal Commission to investigate charges of experimental cruelty, and though the Commission discovered no significant mistreatment of laboratory animals, it did recommend that vivisection be regulated by the state. The Cruelty to Animals Act of 1876 resulted, bringing experimenters and their laboratories into a system of registration and inspection, and requiring the administration of anesthesia (the 1876 Act was replaced in 1986 by the Animals [Scientific Procedures] Act) (French; Ritvo; Turner; Ryder, 1989).

Like so many pieces of legislation, the English Cruelty to Animals Act was a compromise that pleased neither side. Scientists regarded it as an insulting interference with their search for truth, antivivisectionists saw it as a skimpy fig leaf for scientists' arrogance. In truth, many proponents of animal welfare were placated by the requirement of anesthesia, but others noted the law permitted experiments without anesthetics if drugs would interfere with a potentially valuable study, insisted the inspection system was inadequate to insure anesthetics would be used in ordinary experiments, and declared that even when anesthesia was employed, the deprivation of freedom and life suffered by the animals was unacceptable cruelty. The 1876 law actually roused antivivisectionists to more vigorous opposition, because it struck them as official hypocrisy—it claimed to rescue animals from suffering when in fact it gave legal blessing to their confinement and killing.

Objections to animal experimentation now came to be broadcast more loudly than ever, and began to appear in other countries, including the United States, where Henry Bergh launched an antivivisection movement in the 1870s (Rupke). The arguments raised against vivisection were not essentially new. As in the eighteenth century, the utility of vivisection experiments was denied, corruption of the experimenters' character was alleged, and, most important, the sacrificing of animals' lives for human comfort was condemned as fundamentally immoral. Ultimately, practical benefits from animal experiments were deemed irrelevant, as sinfully earned as if they had been derived from painful experiments on humans.

Yet it was the supposed utility of vivisection that gave experimentation overriding significance in the early formulation of a philosophy of animal rights. If one wished to extend animals the same rights as people, treating them as ends in themselves rather than as means to humans' ends, animal experimentation was the purest test case. The ends supposedly achieved by vivisection—saving human lives and relieving suffering—were clearly far worthier than the ends obtained by hunting, trapping, butchering, or other forms of animal slaughter. If the principle of equal rights for animals could be shown to obtain in the laboratory, it would necessarily obtain everywhere else. It was vitally important as well that experimentation was the one form of animal abuse practiced exclusively by educated and refined people, by an elite who should serve as models of civilized behavior for the rest of society. If scientists could not be made to recognize the moral claims of fellow creatures, what hope was there for educating drovers and butchers? The very nobility of the ends of medical research made (and makes) it the most attractive target for animal rights marksmen. Thus Henry Salt's 1892 treatise—Animals' Rights Considered in Relation to Social Progress—attacked every form of animal abuse, but singled out medical research as "the ne plus ultra of iniquity"(p. 102).

By 1900, however, the question of the utility of animal experimentation had blown up in the faces of antivivisectionists, for animal research was finally delivering its long-promised benefits. The newfound power over diphtheria, for so long the gruesome slayer of innocent children, was particularly important for eroding public empathy for innocent laboratory animals, and with the advent of the wonder drug era in the 1930s, criticism of animal experimentation effectively disappeared.

There followed several decades of dormancy, but during the last third of the twentieth century opposition to animal research underwent a dramatic resurgence. The extraordinary expansion of government funding of medical research in the post-World War II decades markedly increased the number of animals used in the laboratory; nearly 30 million warm-blooded animals were being used for research annually in the United States by 1980, and the number would reach an estimated 60 million by the early 1990s. During the 1970s and 1980s, furthermore, several instances of scandalous abuse of laboratory animals were brought to light (Fox; Finsen and Finsen). At the same time, studies demonstrating complex social interactions and the use of language within many species strengthened humans' feelings of kinship with higher animals, while heightened awareness of the endangerment of whole species by human activities fostered resentment of all forms of animal mistreatment (Wise; Clark). Finally, just as the political and religious trends of the late eighteenth century generated broad social sympathy for oppressed people, which was then extended to animals, so the late twentieth century's sensitivity to racial and sexual discrimination revived motivation to be just to all creatures; in 1975, the term speciesism was introduced to parallel racism and sexism (Ryder, 1975).

Within this environment, the ethics of animal experimentation became the subject of serious philosophical analysis. Particularly influential critiques were provided by Peter Singer, whose 1975 Animal Liberation presented a utilitarian argument against speciesism, and Tom Regan, who in 1983 advanced the case for animals' possession of inherent rights to liberty and life. By both analyses, animal research is a morally impermissible way of pursuing science (Singer; Regan). The philosophy of animal rights was translated into practical action by a number of organizations, most notably the Animal Liberation Front (ALF), founded in 1976, and People for the Ethical Treatment of Animals (PETA), established in 1980. The former group, as its name implies, has gone beyond the conventional activities of picketing laboratories and publicizing scientists' violations of animal rights principles, to the invasion of research facilities to free experimental animals and destroy property; estimates of the property damage caused by the ALF are in the millions of dollars (Finsen and Finsen; Petrinovich; Ryder, 1989).

The recent attacks on animal experimentation as unethical have, of course, provoked responses from the medical research community. For the most part, the reaction has been to bluntly assert the primacy of human interests over those of animals, and to emphasize the many medical advances that have come from animal research. There have also, however, been attempts to refute the animal rights position on its own terms, through strict philosophical analysis (Fox). Additionally, a great deal of consideration has been given to the "three Rs": reducing the numbers of animals used in experiments; refining procedures so as to lessen animals' discomfort; and replacing animals when possible with alternatives such as tissue cultures and mathematical models (Russell and Burch; Smyth; Rowan). Beginning in the late 1980s, in fact, several major producers of cosmetic products started abandoning animal testing; the publicity those companies have given to their action is a clear indication of continuing public uneasiness over the morality of animal experimentation (Welsh).

james c. whorton (1995)

revised by author

SEE ALSO: Cloning: Scientific Background; Harm; Hinduism, Bioethics in; Jainism, Bioethics in; Moral Status; Pain and Suffering; Veterinary Ethics; Xenotransplantation; and other Animal Research subentries


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