Major Conceptual Changes in the History of Science

 

A paradigm shift, a concept established by physicist Thomas Kuhn in 1962 (Lecture 22), is a fundamental change in the basic concepts of a scientific discipline. It highlighted the significance of revising the foundation of the knowledge pyramid; that is, questioning and scrutinizing rudimentary postulations can provide innovative perspectives. The history of science consists of countless such revisions of basics knowledge. Here we will focus on three major changes in scientists’ understanding of the natural world, particularly in the field of psychology, biology, and physics, that were not necessarily paradigm shifts, but they provided a distinct approach from previous comprehensions and widened the perception of the natural world.

 

Prior to psychology, the human brain had been widely dissected and experimented with: neuroanatomist Franz Joseph Gail had been studying the various parts of the brain since the 1800s (Lecture 14); however, it was not until neurologist Sigmund Freud’s psychoanalysis in the 1920s that illuminated the understanding of the human mind. Freud was the founder of psychoanalysis. The concept central to his study of the human mind is the unconscious. By investigating the hysteria of his patients, he explained how ideas and thoughts can be repressed and removed from consciousness but yet remained in the mind. Freud was convinced that hysteria is a phenomenon inside the mind of the patient and is thus not caused by an external process. Based on this principle, he presented a topographical perspective of the psyche, comprising id, ego, and super-ego: the id is the instincts and impulses that push humans into action, the super-ego, on the contrary, is the internalization of cultural and moral rules that counteracts the impulses, and the ego is the regulating agent that mediates between the id and the super-ego (Lecture 14). Freud believed that the mind is mostly within the subconscious, and by exploring the deepest corner of the subconscious, he was able to figure out the mechanisms of the human mind.

 

Although Freud painted a vivid picture of the human mind, his postulates are at most a hypothesis, for it is impossible to prove the existence of the id, ego, and super-ego scientifically. So thought John Watson, a psychologist. Watson was the founder of behavioral psychology (Lecture 14). He argued that the inner workings of the mind were introspective and difficult to examine; instead, the study of the human mind should be based on observable behaviors. Watson aligned psychology with chemistry and physics, arguing that psychology should be a science of behavior. Emphasizing objective and experimental practices to study the human mind, Watson believed that an external stimulus signals and changes individual behavior; therefore, the environment that provides the stimulus is responsible for shaping behavior. Extended from this understanding, his ultimate goal was “to learn general and particular methods by which I may control behavior,” (168, Watson). Just like how parental actions can change a child’s beings, he believed that with the correct stimulus, he could completely predict and control one’s behavior. Freud and Watson approached the same problem — the human mind — with disparate angles. In contrast to Freud’s psychoanalytic approach, which was to study the human mind from the inside, Watson examined behavioral reactions to a stimulus, one that approached the human mind from the outside. Watson’s approach also allowed psychology to be quantified; that is, valid experiments based on observations of behaviors made psychology a science and not a branch of philosophy anymore.

 

In biology, multiple naturalists had endeavored to find patterns in nature, so was Georges Louis LeClerc de Buffon (Lecture 9). His comparisons of animal structures led him to conclude that species did change over time; however, it was not until his student Jean-Baptiste Lamarck proposed a mechanism for such gradual change. Lamarck proposed the notion of inheritance of acquired characteristics in 1809 (Lecture 9) to explain how species had changed and how life became more complex. The physical characteristics or organs of a parent organism would be strengthened and enlarged when frequently used and would be reduced and extinguished when disused. (119, Lamarck) Such adjusted characteristics could pass on to the offspring, causing a change of the species over time. Birds who want to fish without wetting its body will attempt to lengthen their neck, which results in remarkable lengthening over time; thus, all water-side birds have long necks. (120, Lamarck) Such explanation also offered a mechanism for species to start simple and consistently develop complexity. 

 

Naturalist Charles Darwin did not buy this. After his voyage on the HMS Beagle, he suggested the principle of natural selection in his 1859 book On the Origin of Species in substitute for the inheritance of acquired characteristics for the mechanism of evolution (Lecture 10). According to Darwin, variations caused by random, unpurposed mutations that arose in individual organisms are put under the examination of nature, where it “rejects that which is bad, preserving and adding up all that is good” (84, Darwin). This is because only those that can survive the environment have the chance to produce offsprings who share similar traits, passing the traits through generations: “the swiftest and slimmest wolves would have the best chance of surviving, and so be preserved or selected.” (90, Darwin) The process happened over vast periods, and organisms living in a different environment that favored different traits branched out from the common ancestor, forming different species. Both principles were a great leap from the orthodox belief of creationism, especially at a time when the church represented the highest authority, as they both removed the need for a creator of life. Darwinian natural selection, nevertheless, provided a more accurate description of the natural world than Lamarckism. It changed, if not the thousand years of zero knowledge about evolution, the 50 years of Lamarckism understanding, paving the way for later genetics and modern evolutionary synthesis.

 

Just when the crowning accomplishments in physics of the theories of electricity, heat, light, and magnetism were thought never to be able to be duplicated in the coming years came Albert Einstein and his Theory of Relativity that revolutionized the understanding of the physical realm in late 19th century. The classical Newtonian world was described by the traditional Euclidean space that was uniform, absolute, and fixed; however, the Theory of Special Relativity portrayed space, time, and even mass relative to individual reference frames (Lecture 7). Simultaneity was no longer guaranteed. Einstein’s Theory of General Relativity further visualized the space as a flexible piece of cloth that can be curved by the matter and energy in the space, in contrast to the flat, hard Euclidean space (Lecture 8). Although the theory of relativity only diverges with the classical view at high velocity, it provided a drastic and accurate shift of understanding of the macro world. It allowed physicists to probe the limits of spacetime and explore the universe; it elevated theoretical physics and theorists into the mainstream at an era when experimental physics was greatly praised for its applications; it shed light on cosmology, particle physics, and quantum mechanics. Its impact on physics and the world was phenomenal. “Immortality awaits the man who can overthrow Einstein.” (23, The New Yorker) 

 

Most science explorers took their education and the contemporary scientific consensus for granted, not John Watson, Charles Darwin, and Albert Einstein: they doubted the norm and dreamt the undreamt. They allowed scientists to take a step closer to accurately describe how the world came to be, what the world really is, and who we really are. Behaviorism, natural selection, and relativity all brought major changes to the understanding of the natural world and reconstructed the way we perceive the world.

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Bibliography 

 

Darwin, Charles. “Natural Selection.” On the Origin of Species, UK, John Murray, 1859, pp. 80–130.

 

Lamarck, J. B. “Of the Influence of the Environment on the Activities and Habits of Animals, and the Influence of the Activities and Habits of These Living Bodies in Modifying Their Organisation and Structure.” Zoological Philosophy, An Exposition with Regard to the Natural History of Animals, London, MacMillan and CO., Limited, 1914, pp. 106–27.

 

“Scientist and Mob Idol - 1.” The New Yorker, Dec. 1933, pp. 23–26.

 

Watson, John B. “Psychology as the Behaviorist Views It.” Psychological Review, vol. 20, no. 2, 1913, pp. 158–77.

 

Professor Patrick McCray. Lecture 7, 8, 9, 10, 14, 22. [PDF file]. Retrieved at 2021, July 31 from HIST 20 Gauchospace