During the 18th century, one of life’s most puzzling questions caused the worlds of scientific inquiry and theology to clash head on. Namely, how were the rocks that comprise earth’s surface created and arranged into the current landscape? Or more generally, what are the forces that shape the earth’s surface? These questions do not pertain to the existence of god, but instead question whether natural laws or supernatural forces have formed the earth’s landscape throughout our planet’s history.
The prevailing theories of the 18th century on the origin of rocks are as follows: James Hutton’s theory of plutonism stated that rocks were formed from processes driven by heat contained within the earth’s interior, while Abraham Werner’s theory of neptunism stated that rocks were precipitated out of an ocean that once covered the entire earth. Each theory has different implications on the forces that control Earth’s landscape. As you will see, Hutton’s theory would eventually form the foundation for modern geology and, further, prove that supernatural intervention is not necessary in shaping the earth’s landscape.
During the 18th century neptunism was a dominantly accepted theory within the scientific community. Individuals gravitated toward Werner’s theory of neptunism because it did not dismantle the teachings of theology. Werner never proposed forces that could cause the entire surface of the earth to be covered in water. He also did not propose forces that could cause this sea to retreat from the land. Because Werner neglected to identify these forces, theologians were free to view this ancient ocean as a Biblical flood or act of god. Werner was an excellent teacher so his theory of neptunism disseminated into the scientific community expeditiously during his lifetime.
A French paleontologist named George Cuvier further supported the success of neptunism. Cuvier was working in the Paris Basin and recognized gaps in the fossil secession that represent mass extinction events. Cuvier attributed these gaps in the fossil secession to short lived, catastrophic events. While Cuvier acknowledged that drastic changes in sea level could contribute to mass extinction, he never identified the forces that could cause the sea level to rise and fall within a relatively short time period. Because Cuvier did not identify these forces, theologians could continue to justify acts of god within the natural history of our planet.
The basic notion proposed by neptunism and catastrophism is that the forces that have shaped the Earth throughout natural history are not consistent. Because these forces were not considered constant, 18th century scientists had no controls by which to estimate the age of the Earth. Therefore, theologians were able to believe that the earth was only thousands of years old.
However, by the beginning of the 19th century, the majority of the scientific community would abandon the theories of neptunism and catastrophism for those of plutonism and uniformitarianism, proposed by James Hutton and Charles Lyell. According to these theories, supernatural intervention would no longer be necessary to shape the earth’s landscape. Therefore, this transition into the 19th century marks the emergence of modern geology, or a divergence between the scientific study of geology and the spiritual teachings of theology.
During the 18th century, James Hutton was only beginning to be recognized for the theory of plutonism. Hutton’s theory states that rocks were formed from processes driven by heat contained within the earth’s interior. Although Hutton never suggested the forces that could cause large amounts of heat to be contained within the earth, he did identify several forces working to shape the earth’s landscape. Hutton realized that rocks could be eroded, deposited into the ocean, compacted into rock and lifted back onto land by physical mechanisms. The progressive aspect of Hutton’s theory of plutonism is that it functions purely on natural laws. Although the theory of plutonism would eventually form the foundation of modern geology, his theory was not widely accepted during his lifetime.
The man responsible for spreading Hutton’s theory of plutonism to the scientific community was Charles Lyell. Lyell would eventually write the first modern geology textbook in 1830 entitled, Principles of Geology. In this book, Lyell reworks Hutton’s rock forming processes into a more comprehendible form. Uniformitarianism is the idea that the processes that form earth’s surface are very slow and occur at a constant rate. Therefore, the theories of plutonism and uniformitarianism state that gradual processes observable at earth’s surface and controlled by natural laws have shaped the earth’s landscape through an inconceivably vast natural history.
Although James Hutton was the scientist ultimately responsible for abolishing the notion of supernatural forces in the earth system, Hutton himself was a believer in god. Hutton simply believed that god created the perfect machine; one that does not need divine intervention in order to function. By promoting these ideas, Hutton made the existence of god irrelevant in the formation of earth’s landscape. In doing so, Hutton liberated the conflicted minds of scientists from the irrelevant existence of god. By forming the foundation on which modern geology developed, Hutton became the most influential geoscientist of his time.
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