Teaching the History of Geology

The content and form of a course in the history of geology are dictated by the nature of the subject matter, the conceived purpose of the course, the background of the instructor and the students who participate, and the availability of appropriate readings. In an undergraduate course just offered by the Brooklyn College Geology Department, half the class were geology majors, half non-science majors. The stated aim of the course was epistemological: a consideration of how one comes to believe something. Investigation was pursued through a comparison of different historiographic accounts of major ideas, episodes and figures in the history of geology: the age of the earth; the meaning of fossils; 17th and 18th C ‘theories of the earth’; the denudation dilemma; the basalt and granite controversies; directionalism; Lyell's ‘uniformitarianism’; fluvialism, diluvialism, and glacialism. Where possible, original writings were consulted; the recent advent of a low cost reprint of Lyell's "Principles" was particularly fortunate. Inevitably, the methods, boundaries, controls, and workings of science were questioned, as was the meaning of ‘truth.’ The history of geology is a particularly useful tool for such an epistemological investigation because, prior to its mid-19th C professionalization, geology was relatively free of arcane jargon or sophisticated technology; thus, it is accessible to students with minimal scientific background. The students came to appreciate the relative character of knowledge and the probable evanescence of current belief. As for myself, trained as a geologist, I came to respect the insights and problems of historians, philosophers and sociologists, and to appreciate the pitfalls and opportunities of teaching in an area beyond one's expertise. Going out on a limb, I suggest that a course in the history of geology could serve well as partially fulfilling undergraduate science requirements.