James Hutton’s Theory of the Earth , first published in 1785, was considered completely new by his contemporaries, different from anything that preceded it, and widely discussed both in Hutton’s own country and abroad—from St. Petersburg through Europe to New York. Yet a recent trend among some historians of geology is to characterize Hutton’s work as already behind the times in the late eighteenth century and remembered only because some later geologists found it convenient to represent it as a precursor of the prevailing opinions of the day. Painstakingly researched, richly referenced, and full of interesting stories, this Memoir shatters that line of thinking and restores Hutton’s standing as the father of modern geology, his ideas fully relevant to the geological problems of his day.

The discovery of geologic time revolutionized scientific thinking and led to the development of the modern Earth sciences. Less appreciated, however, is the fact that geologic time has had far-reaching cultural and societal consequences that go well beyond its founding influence upon the geosciences. This essay summarizes the literature describing the difficulties students encounter in understanding deep time, provides an overview of the historical development and cultural relevance of deep time, and suggests ways to increase students' understanding of the significance of geologic time.