The theoretical system Lyell presented in 1830 was composed of three requirements or principles: 1) the Uniformity Principle which states that past geological events must be explained by the same causes now in operation; 2) the Uniformity of Rate Principle which states that geological laws operate with the same force as at present; 3) the Steady-state Principle which states that the earth does not undergo any directional change. The three principles form a single thesis called uniformitarianism which has been repeatedly (...) questioned and which has been reputed to be unable to face the competing directional synthesis based on the theory of the earth's cooling down. As a result, the significance of Lyell's system has been reduced to a simple actualism which admits the validity of the only Uniformity Principle. I believe that the only way to understand Lyell's role in the history of science is to maintain the unity of his synthesis. To show the Newtonian roots of this synthesis I will compare Lyell's principles and Newton's Rules of Reasoning. I will conclude with an analysis of the methodological function of principles in Lyell's scientific endeavour. (shrink)

Earth-shaping catastrophic events have long focused the attention of the geographical and geological sciences, and captured the public imagination. During the past 40 years, neocatastrophism has emerged as a key paradigm that reflects widespread changes involving cultural, scientific, political and technological spheres. Nonetheless, the extent, chronology and origin of this trend are equivocal. Here, we use Google Ngram to quantitatively explore the recent development of catastrophism. We elucidate a discernable rise in neocatastrophic thinking during the last quarter of the twenty-first (...) century that can be linked to the environmental awakening of the 1960s. It is suggested that these discourses of ‘shock’ and ‘fear’ partly correspond to a media-driven dramatization of natural hazards, exploited by scientists and journalists to attract wider readership. (shrink)