The concept of uniformitarianism is commonly oversimplified in geological textbooks as "the present is a guide to interpreting the past" (or words to that effect). This explanation, however, is not correct about the true meaning of uniformitarianism. In order to understand uniformitarianism, one must examine its roots in the Enlightenment era (c. 1750–1850) and how the term has been distorted in meaning since that time.

Geology is a historical science, yet the phenomena and processes studied by geologists operated under non-historical natural systems that are independent of the time in which they operated. It is clear from the insights of one of geology's founding fathers of the Enlightenment era, James Hutton (1726–1797), that he understood this fact very well. In Theory of the Earth (1795), he stated: "In examining things present, we have data from which to reason with regard to what has been; and, from what has actually been, we...