Ages past: Ancient geology and modern preconceptions

In many accounts of the history of the earth sciences, geology is identified as beginning in the seventeenth century against a backdrop of religious superstition and ignorance. A leading figure in those histories was James Hutton (1726–1797) who is credited with formulating the idea of ‘deep time’ based on his own observations of the rock cycle punctuated by unconformities. In his writings, and in many later history accounts, the contributions of classical thinkers are largely ignored. Although several contemporary historians of geoscience have commented already on the modernity of classical thinkers, the purpose of this paper is to document that classical awareness of deep time was more pervasive than is generally acknowledged. This paper argues that geology was, all told, one of the most advanced sciences in classical antiquity and enjoys a remarkable conversance with its modern successor. Classical naturalists and philosophers made scientifically valid observations and interpretations of many geologic processes including volcanism, sedimentation, hydrology, tsunamis, and fossil beds. Consequently, classical naturalists and philosophers should be considered worthy antecedents of modern geologists.