Hutton, James (1726-1797)

Scottish physician

James Hutton, a Scottish physician and farmer, is considered by many to be the father of geology. Hutton observed geological changes and theorized that the forces that were changing the landscape of his farm were the same forces that had changed Earth's surface in the past. He built on this theory to form his principle of uniformitariansm in 1785.

The principle states that current geological processes, for example volcanic activity and erosion, are the same processes that were at work in the past, and will still be at work in the future. A summary of his theory is the phrase "the present is the key to the past." Hutton watched these slow changes occurring on his own farm and theorized that over time, a stream could carve a valley, rain would erode rock, and sediment could accumulate and form new landforms. He realized that these forces must be acting very slowly, and therefore, Earth must be older than theologians at the time argued it to be. He published this theory in 1790 in his work The Theory of the Earth.

Modern evidence supports the essential elements of Hutton's theory. Earth is approximately 4.6 billion years old, and there is abundant evidence that slow processes have worked to mold and shape the planet. Moreover, the same forces that acted in the past are active now, even though the relative rates may vary over time. When Hutton published his theories, however, they were not met with enthusiasm. Uniformitarianism went against both religious beliefs and the theory of catastrophism, the accepted theory of the time. Catastrophism states that the earth was formed not by slow processes, but by violent, worldwide disturbances such as earthquakes and floods. It was not until the nineteenth century that Sir Charles Lyell, in his 1830 work Principles of Geology, popularized the theory of uniformitarianism.

James Hutton was not only known for his uniformitarianism theory, but also for developing the concept of the rock cycle. This theory describes the interrelationships between igneous, sedimentary, and metamorphic rocks. The matter that makes up these rocks is neither created nor destroyed, but instead transformed from one rock type to another. He also suggested that the study of the earth be called "geophysiology." Hutton's theories about Earth as an entity that undergoes dynamic cycles are considered by some to be the basis of the Gaia hypothesis, the concept of the "living earth."

See also Earth (planet); Geologic time