As a young student in Copenhagen, Nicholas Steno was well acquainted with the work of the French philosopher and scientist René Descartes and adopted his methodological principles and many of his theories as well. Empirical anatomical research on glands, muscles, and brain gradually made Steno more and more critical of Descartes’ stringent but wholly deductive reasoning. Nevertheless, on a deeper level, most of Steno’s path-breaking research in anatomy, as well as in geology, operated within a mechanist Cartesian framework, and several of his path-breaking discoveries can be linked to his testing of crucial points in the Cartesian theory of how the “human machine” works. It might be a little too much to cast Steno as a Popperian avant la lettre, but viewed from a Kuhnian perspective, Cartesianism can aptly be described as Steno’s research paradigm.

Steno’s life was punctuated by two conversions: (1) from anatomy and medicine to geology, and (2) from Lutheran to Roman Catholic confession. Why was Steno (1638–1686) motivated to solve geological problems soon after he entered the Tuscan region of Italy? Was there any link between his scientific conversion and the religious one, which occurred almost simultaneously and produced a revolution in his life? The origin of marine fossils found in mountains had been debated in Italy for one and a half centuries. Leonardo da Vinci (1452–1519) had already given a modern scientific explanation for the problem. Ulisse Aldrovandi (1522–1605) later tackled the problem with an experimental-taxonomic approach (his famous museum and studio), and it was he who coined the word “geology” in 1603. Italy provided spectacular exposures of rocky outcrops that must have impressed the Danish scientist who had lived in the forested north European lowlands. Since the time of Giotto and his successors, such as Mantegna, Pollaiolo, Leonardo, and Bellini, the imposing Italian landscape had stimulated the visualization of geology. Inevitably, science and art merged perfectly in the work of painter and paleontologist Agostino Scilla (1629–1700). Steno was methodologically skilled and intellectually curious and was thus open to the stimuli that Italy had to offer in order to unwittingly rediscover, after Leonardo, the principles of geology and to solve the problem of fossils. Steno’s inclination to detailed “anatomical” observation of natural objects and processes as well as his religious conversion were influenced by his acquaintance with the circle of Galileo Galilei’s (1564–1647) disciples who formed the Accademia del Cimento. They were firm Roman Catholic believers. To the inductive mild rationalist and open-minded Steno, this connection could not be dismissed, and it prepared him for changing his paradigms for the sake of consistency. This occurred when a Corpus Domini procession triggered a revelation and led to his religious conversion.

Nicholas Steno (1638–1686) always started from his own observations, either in anatomy and geology or regarding theological truths. This was in line with Galileo Galilei’s principle that when investigating physical questions, one should not begin with biblical texts. Thus, Steno had an advantage over other theologians like Vincent de Contenson (1641–1674) who adopted old-fashioned scientific theories from classical antiquity. Though Steno’s conception, in contrast to Athanasius Kircher (1601–1680), emphasized the accidental nature of Earth’s history, it still left a place for the Creator. When observing the geological structure of Earth, Steno concluded that shifts of Earth’s surface were part of nature’s corruption by the original sin of mankind, referring to biblical Adam and Eve, Genesis 3:1–24. Therefore, Steno, who was the first to present a history of Earth before the Deluge, viewed subterranean veins as places not created by God at the beginning of time, but instead within a geological process having begun with the malediction of Earth; in other words, nature was disturbed by original sin. For him, God’s original purpose for Earth’s properties remained hidden and unknown to men, because most of them at first glance seemed to be useless for life on Earth. Both before and after Steno’s conversion, his standpoint remained fundamentally the same and supported his own geological insights.

It has been suggested that Robert Hooke had some influence upon Nicholas Steno’s forming geotheory, but decisive evidence has not yet been given. To reconsider the Hooke–Steno relationship, this paper examines Boyle–Steno relations by not only comparing their texts but by assessing a mediating role played by Ole Borch. In investigating the origin of the Stenonian terminology “solids within solids” in his Prodromus (1669), I shall point to two possible sources. One is represented in Steno’s first dissertation De thermis (1660), which was composed under the influence not only of scholastic themes but also of physiological textbooks of the age. The other is Robert Boyle’s texts on petrifaction and mineralogy written in the 1650s and 1660s, which appeared in part in 1661 and 1672, and which were ultimately published in 2000. A similar terminology for the relations of fluid/solid bodies is also observed in Hooke’s first dissertation on capillary action (1661), Attempt for the Explication of the Phaenomena , apparently deduced from the Boylean concept of fluidity and firmness. On the other hand, Steno’s mentor Borch met Boyle in 1663 during his journey through Europe, and it is likely he transmitted Boyle’s idea to Steno, though Steno himself made no reference to Boyle by name. The fact that Boyle’s works were a possible common source for Hookian and Stenonian geoscientific thought leads us to reconsider Boyle’s contribution to the history of early modern geotheory.

Historians of science have long known that conceptualization is a prerequisite for science, and geology is no exception. Art history records that the Western concept of landscape preceded the science of landscape, and it also helps explain how it could be that one of Europe’s preeminent seventeenth-century anatomists, Nicholas Steno, founded the science. The Renaissance rediscovery of Arabic and Greek geometry and artists’ unprecedented use of it to describe nature, particularly the structure of the human body, facilitated the concept of landscape as a material object of integrated parts and functions. That anatomical analogy, which Steno embraced, replaced and had far fewer associations than the earlier analogy of the human body as a microcosm for the macrocosm of Earth and the greater cosmos. In turn, the new paradigm facilitated the modern understanding of evolution of landscape and life. These developments were part of the larger, contemporaneous spatial reorganization within Western civilization that encompassed revolutions in economics, land ownership, distribution of political power, etc.—in a word, the Western experiment in democracy. They suggest that contemporary creationists’ rejection of evolution reflects anxiety over the individual’s potential for change in a democracy. These associations are strengthened by a comparison with the case of China, which eschewed geometry until the nineteenth century. China did not develop a geometric sense of either landscape or life until well after Europe had done so, despite the geological discoveries that China is credited with having made well before Europe entered the Renaissance. Nor did China undergo the geometric reorganization of its bureaucracy and power structures, as did the West. Consequently, China held fast to a very different idea of evolution of landscape and life in nature and of the individual in society.

Abstract Geology, as far as it had advanced 50 years ago, was largely based upon the simple principle first enunciated by Nicholas Steno—that of superposition. But no successful chronology could have been worked out in the early days had it not been for the presence of invertebrate fossils in the stratified rocks. Invertebrate paleontology, therefore, since the beginning of the nineteenth century, has been an integral part of geology. Until the dawn of the evil days of specialization 40 or 50 years ago, most geologists had a working knowledge of fossils, and the number of those who could be designated as invertebrate paleontologists rather than geologists was small. That there were any such seems to be due largely to the fact that in all ages there have been those who were attracted by “natural curiosities”. There were collectors of fossils centuries before there was a science of paleontology. Fossils were described and figured and traded by people who could not decide whether they were organic or inorganic. This bit of well-known history is repeated here because it explains why so many of the contributions of the invertebrate paleontologists are descriptive. In the first place, such work is necessary; in the second, most invertebrate paleontologists, sensu stricto , started as amateurs of their subject and remained such, even though, in some cases, their labors provided them a livelihood of a sort.