The neglected early history of Geology: The Copernican Revolution as a major advance in understanding the Earth: COMMENT

Abstract

Alvarez and Leitao (2010) propose a completely new way to look at the early history of geology, with the declared purpose of raising awareness among earth scientists of the historical development of their discipline, and giving a better place to earth sciences with respect to what is generally considered to constitute science within contemporary society. To that aim, they defend the thesis that the Copernican Revolution, generally assumed as the founding event of modern science, could actually be viewed as offering the very fi rst understanding of Earth as a planet, and hence as a major advancement not only in astronomy and physics but also in the fi eld of geology. The aim of the present discussion is to analyze the epistemological idea of geology on which the thesis defended by Alvarez and Leitao is grounded, because, despite the positive intentions of the authors, it risks lowering the appreciation of geology as a discipline, heavily rooted in a different and specifi c epistemology, namely that of the historical sciences. Their reasoning, by contrast, is completely biased by the defi nition of science generally assumed for physical–mathematical sciences. The idea of seeing heliocentric Copernican theory as a truly Earthcentered theory in the Alvarez and Leitao paper is based more on socialpsychology arguments than on analytical or epistemological grounds. It is certainly appealing to call attention to the change introduced by the Copernican Revolution of the meaning of the word “earth” itself, and the derivative general perception of 17 th century society. However, the “word