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The Age of Enlightenment and the Scientific Revolution
The 15th century, known as the Age of Enlightenment, brought a paradigm shift in our relationship with the natural world. Copernicus (1473-1543) and Galileo (1564-1642) were the catalysts for this change, showing that instead of the earth (and by extension, human beings) being the center of the universe, the earth was part of a much larger solar system. This discovery shook the idea of the church as the focal point of divine power on earth. Research into the natural world came to be viewed less as a religious pursuit and more of an expression of human reason seeking to make sense of the world in order to improve the human condition. Vesalius (1514-1564) revived the ancient practice of dissecting human corpses to understand the body and held public demonstrations, usually using dogs. His contemporary, William Harvey (1578-1657), did further research on circulation, respiration and blood pressure, giving public demonstrations with live deer. The ability of one biological system to stand in for another was taken for granted, with the reasoning that blood was blood, bone was bone, and animals ate, reproduced, walked and slept just as humans did.
To survive without using animals would not have been possible at this time; they were essential resources as food, clothing and labor. Consideration was not given to whether or not an animal suffered pain. Because there was no knowledge of anesthetics at this time, physical pain was a reality of daily life for both people and animals.From the early 1600s, the Renaissance saw a renewed interest in science and philosophy, and a rift between science and faith began fermenting. Bacon (1561-1626) introduced the idea of induction into experimental science, further separating the study of science from faith. Descartes (1596-1650) fortified the trend of separating the physical body from the mind (only the mind was capable of a soul) and this mind/body duality became an influential concept. Descartes and his contemporaries were trying to reconcile the old ways – i.e., religion – with the new way of science. Outright rejection of the divine was not feasible, and the solution was to divorce the two, leaving spiritual matters to God and the church as long as the church agreed that the physical world was the jurisdiction of the state, with science as the purveyor of knowledge.
The dilemma was how to reconcile that pain with the need to further understand the natural world in order to improve the human situation. Descartes held that animals do not suffer in the way that humans do because they cannot understand pain rationally. For Descartes the absence of rational ability left animals in a lower category than human beings. The argument over whether animals had souls was a solution to the dilemma. Since only rational beings could have souls, it followed that those without souls were not on the same level and it was decided that animal pain did not “count” in the same way as human pain did.
This solution — that the body and mind (soul) were separate — became a foundation of the “new” science. The church was able to continue as a social force, and religion could maintain its place in society. But the power of traditional religion over the public was no longer as strong because science was now taking over for many as a source of authority. This tension between the religious and the secular is a continuing issue for us in contemporary society. This separation between church and state left the arena open for scientific investigation to continue; as part of the shift in power, as biological entities, animals were no longer within the domain of the church. They were no longer brought to the priests or herbalists, but to the scientists and in particular, to a newly growing professional group, the veterinarians. Animals were understood as a kind of prize in the struggle for power between the church and the secular society.
In another turning point, Newton (1642-1727) set forth The Mathematical Principles of Natural Philosophy, espousing the view that natural laws, created by God, used the language of mathematics. To understand the natural world, precise analysis of phenomena was the method of choice. Boyle (1621-1691) continued in a similar vein, setting forth laws that laid the foundation for modern chemistry. More and more, the scientific method involved examining phenomena to establish the mathematical laws at work in the system under study. Although using animals as “biological systems” continued to be a valid methodology, not all scientists were comfortable experimenting on animals dispassionately to understand the natural world.
Several eminent scientists, including Boyle and Robert Hooke (1635-1703), expressed concern for the welfare of their subjects, though they remained convinced that the costs to the animals were justified by the results of their research. Boyle had used kittens in public demonstrations of a vacuum and spoke of excluding a kitten that has survived one air pump experiment from further trials out of humane concerns. Hooke, using dogs for research into blood circulation, wrote to Boyle that he was unable to repeat a particular procedure because it was cruel.
During the Scientific Revolution, as universal laws replaced personal intercession by the saints or God, the centrality of the individual and subjective experience was no longer as important as seeing how a person (or animal) fit into the larger scheme of things. Science became viewed as objective, and so, the laws of science were above the laws of the individual. Inquiry into the “right relationship” between animals and people was of concern to philosophers as they, like scientists, tried to formulate a new ethic combining the old religious traditions with the new knowledge gained from science. The Scottish philosopher David Hume (1711-1776) disagreed with the Cartesian notion of animals being incapable of reason, attributing rationality, or at least the capacity to reason, to some animals.
The 1700s were the period when biology began to come into its own as a field of study. The idea that the natural world could be examined rationally increasingly supplanted the sense that the world was a manifestation of divine will. Building on the ideas of Bacon and his inductive method, Magendie(1783-1835) established modern physiology, discovering the co-functioning of organs. His student, Bernard(1813-1878), is known as the father of experimental physiology. Bernard proposed that a valid experiment was one in which only one parameter at a time could be changed. Only in this way could objective results be achieved. Again, they were contesting the established tradition of religious belief in supernatural powers and divine origins.
Bernard was equally critical of clinical data calling it unreliable. His view was that only in the laboratory could true objective knowledge be obtained. For Bernard, clinical medicine was open to intuition, superstition and non-substantial claims. His goal was to make the scientific understanding of biological systems on a par with the scientific understanding of chemistry, physics and mathematics. He emphasized the dynamic nature of the body, be it human or animal, calling this energy the “vital force” and insisting that the only way to properly understand this phenomenon was by direct investigation of the living system in its natural state.
Pasteur (1822-1895) and Koch (1847-1910), contemporaries of Bernard, built on previous discoveries, isolating causes of several diseases and developing cures based on scientific data. To put this accomplishment in a broader social context, consider that in Victorian Britain, life expectancy was 42 years. The fact that these new cures worked was an achievement that cannot be overstated. After all, diphtheria and cholera antitoxins, as well as anthrax and rabies vaccines, were all tested on animals. It was powerful validation that applying scientific principles could improve the human condition. As science began to improve the quality of life, the public’s “faith” in science deepened.
At the same time, advances in science provided some of the strongest arguments for imbuing animals with enhanced moral value. In showing that the nervous systems of all vertebrate animals are similar, it could be assumed that activities which cause pain or distress to a human will likewise cause pain and distress to other vertebrate animals.
In 1847, William Morton discovered the property of ether as an anesthetic, and although not all researchers took advantage of this discovery on behalf of animal subjects, many did, including Bernard, and this made the use of animals for science more palatable to many. Because surgical techniques could now be improved and the animals helped to suffer less, animal experimentation began to be a method of choice in medical research.