Nature

Nature is often taken to be the reality of the physical and material world. It is placed in opposition to culture, the product of human intervention and production. Yet historians recognize that nature is actually a product of human culture—a complex concept that has changed according to the views of particular individuals and cultures in history. Nature can be thought of in terms of its components—for example, the cosmos or material substances—and it can be conceptualized as an entity in itself. In both respects the early modern era marked numerous controversies concerning the nature of nature and concerning the makeup and behavior of its constituent components.

Aristotelian Nature

Any investigation of the idea of nature in the early modern era must take into account the Aristotelian framework that was defended well into the seventeenth century. Aristotle explicated his views on nature (physis in Greek) in the second book of Physics, in the seventh book of Metaphysics, and in the first book of Parts of Animals. He considered the natural and the artificial to be distinctly separate entities. Animals, plants, and the four Aristotelian elements—earth, air, fire, and water—exist by nature. A natural thing has an essence that makes it a genuine kind of species. It possesses the principle of movement or change and rest within itself. This principle can entail local motion, that is, growth and shrinkage, or qualitative changes, that is, modifications. Nature is the distinct form of things that have within themselves the principle of motion. That form moves toward its final cause or goal, for the sake of which it exists. In contrast, art can imitate nature but can never be natural. Artificial things do not have a principle of motion. Any change to a fabricated object is accomplished by the actions of an external agent. A tree grows by nature, whereas a house must be built by a builder. Art is separate from nature and is always inferior to it.

The Aristotelian natural world, described most completely in Aristotle's On the Heavens, was made up of two spheres, the sublunar and the supralunar. In the sublunar sphere matter consisted of four elements—earth, air, fire, and water—each of which had a tendency to move to its natural place. Earthly bodies, for example, tended to move down toward the center of the Earth, whereas fiery bodies tended to move up. Motion contrary to such natural motion, as when a stone (made of the element earth) was thrown upward, was unnatural or violent. The region above the Moon was made up of the quintessential element that was entirely different from the four sublunar elements. This fifth element was unchanging and perfect. Its natural motion was circular. Aristotle argued that the elements that made up the cosmos were eternal, rather than created. Matter was continuous. The universe was not infinite but limited, the cosmos was circular, and the Earth was at rest in the center.

Early modern scholars and natural philosophers were thoroughly schooled in the principles of the Aristotelian natural world and in the complex traditions of commentary and discussion that surrounded it. The Aristotelian corpus provided the foundation of the university curriculum. Natural philosophy, which included both the physical and the life sciences, was particularly emphasized in the Italian universities, where it was considered prerequisite to the study of medicine.

Particular discoveries or interpretations that arose in the sixteenth and seventeenth centuries undermined the entire Aristotelian edifice of nature. The heliocentric system of Nicolaus Copernicus (1473–1543) provided an alternative to Aristotelian-Ptolemaic cosmology but also subverted the Aristotelian doctrine of the natural place of the element earth. Galileo Galilei's (1564–1642) comparison of the surface of the Moon to that of the Earth and his discovery of the moons of Jupiter suggested that the supralunar realm was identical to the sublunar. Observations of comets and sunspots suggested novelty in the heavens rather than the presence of an unchanging quintessential element.

Humanism, Platonism, and the New Philosophies of Nature

Renaissance humanism entailed an intellectual movement focused on moral philosophy, history, and rhetoric that included an intense interest in antiquity and the desire to restore Latin to the language of Cicero. By the late fifteenth century humanists had begun to influence the university curriculum. In their rediscovery and extensive study of ancient texts, they reedited the works of Aristotle and brought other ancient works into view. For example, Lucretius's atomism, explicated in the newly discovered On the Nature of Things, could be set against the Aristotelian doctrine of continuous matter. The many Neoplatonic texts that became available from the late fifteenth century provided a basis for the development of new philosophies of nature.

In the Theologia Platonica (1482; Platonic theology) Marsilio Ficino (1433–1499) posited the universe as a hierarchy of being in which a rational soul (that included the human soul within it) was at the center of the universe between the perceptible corporeal world and the noncorporeal intelligible one. Ficino believed that the cosmos and its forces exhibited numerous correspondences among all the different levels. Other natural philosophers, influenced by Ficinian Platonism, developed innovative visions of the natural order. Bernardino Telesio (1509–1588) postulated that the principles of heat and cold constituted the causes of all earthly processes, while the Sun, a unique natural fire, provided the underlying motive force. Telesio's system of nature was characterized by "the living character of everything and the consequent connections between man and the cosmos" (Ingegno, p. 252). Giordano Bruno (1548–1600) endorsed the Copernican system of Earth moving around the Sun but went beyond Copernicus in his description of an infinite universe of innumerable solar systems in which the elemental processes were everywhere the same. Francesco Patrizi (1529–1597) wrote an immense encyclopedia of natural philosophy, Nova de Universis Philosophia (1591; New philosophy of universes), in which he suggested that the illumination of the world proceeds from the first divine light. This illumination, which is both corporeal and noncorporeal, fills all space and motivates all heavenly and earthly processes. It is a hierarchical universe in which soul is intermediary between the corporeal and noncorporeal realms.

The new philosophies of nature often placed the individual human soul in contact with the divine and with the spirits of the noncorporeal cosmos. Many such philosophies included a doctrine of correspondences in which things within both physical and noncorporeal realms reflected and influenced one another. The belief in the ability to exert influence from a distance through correspondence underlay magical outlooks wherein the magus or magician could manipulate divine powers for material ends. Renaissance nature philosophers were often anti-Aristotelian, and they were vulnerable to charges of using demonic magic and of heresy. Patrizi's vast encyclopedia was put on the Index of Prohibited Books by the Roman Inquisition. Bruno was burned at the stake for heresy in 1600.

Natural, Supernatural, Preternatural, Artificial, and Unnatural

Lorraine Daston has noted that early modern views of nature can be investigated only if the modern dichotomy between nature and culture is put aside. The early modern period instead utilized a variety of categories defined vis-à-vis the natural. The super-natural was a category largely created by Thomas Aquinas (1225–1274) in the thirteenth century. He viewed miracles—supernatural events—as God's intervention in the natural order and therefore above that order. A second category, "preter-natural," described events that were highly unusual, "beyond nature," but not supernatural. Examples include monstrous births, bizarre weather, the occult powers of plants and minerals, and other deviations from ordinary natural events. A third category, the artificial, comprised objects fabricated by humans that could imitate nature but could never become part of the natural world. Finally, the unnatural was a moral category used to describe acts, such as patricide and bestiality, that transgressed the natural order ordained by God.

During the early modern era the boundaries that defined these categories were increasingly called into question. Miracles as events brought about by supernatural intervention became contested territory in the context of the Protestant Reformation and Catholic reform movements. A religious movement labeled "enthusiasm" developed in northern Germany, England, and the Netherlands in which members of Quaker and other Pietist religious groups claimed direct experience of the Divine as a result of enthusiastic inspiration. Yet the enthusiasts were condemned as a threat to political order and religious orthodoxy. In the seventeenth and eighteenth centuries enthusiasm and miracles in the present (as opposed to the distant past) became increasingly unacceptable within established political and religious orders.

The category of the preternatural presents a complicated history. From the sixteenth century through the mid-seventeenth century natural philosophers, such as Girolamo Cardano (1501–1576), Pietro Pompanazzi (1462–1525), and Francis Bacon (1561–1626), focused on preternatural events, such as celestial aberrations, monstrous births, and other odd occurrences. Such events became a significant focus of the early scientific societies as even the briefest perusal of the Transactions of the Royal Society attests. By the 1720s, however, these wonders of nature came to be largely ignored. Preternatural phenomena had been subsumed under the natural.

Substantial evidence points to a further development—the disappearance of the boundary between the natural and the artificial. Objects of nature and objects of art came to be interchangeable. In the 1490s Leonardo da Vinci (1452–1519), in his treatise on machines and mechanics, Madrid Codex I, made analogies between natural and constructed objects as a way of trying to understand the workings of each. Little more than a century later Bacon and René Descartes (1596–1650) each insisted upon the identity of the essential attributes of the artificial and the natural. Such identity and interchangeability was evident in the great collections naturalists accumulated in the seventeenth century. These collections displayed a mixed conglomeration of natural specimens, preternatural wonders, and objects made by humans. Human artifice had gained in status, taking its place beside and becoming interchangeable with the myriad objects of the natural world.

Experience and Experiment

Attitudes toward nature were influenced by the growing importance of material objects within society and by the exchange of those objects within commercial relationships that extended across Europe and beyond. Early modern Europeans exhibited a growing interest in conspicuous consumption as well as a fascination with novelty, including objects and marvels from lands recently discovered and colonized. The makers of objects—artisans and men and women skilled in crafts—enjoyed increased cultural status that developed as a result of the growing positive valuation of practice and hands-on experience. Artisans began to value their practices as generative of a kind of knowledge derived from direct and intimate experience with materials and with nature. Artisan-trained individuals and others of various backgrounds wrote books in which they validated their own experience by means of the authority of nature. For example, the potter Bernard Palissy (1510–1589) described his many experiments to find a formula for a new glaze and repeatedly endorsed the value of practice over theory. The physician Paracelsus (1493–1541) not only railed against the book learning of contemporary medicine in the universities but also endorsed direct experience with nature as essential to knowledge concerning the natural world, including knowledge of health and disease. Reading the "book of nature" for Paracelsus entailed experiencing it directly and thereby being able to read God's "signatures," external signs that revealed the internal nature of things.

Bacon's empirical approach envisaged a vast cooperative project of collecting the facts of nature. Bacon hoped to create detailed descriptions of natural phenomena and of processes of the "mechanical arts," such as metallurgy and glassmaking. From such histories, Bacon advocated the creation of axioms that would allow humans to read the "book of nature." For Bacon this book was authored by God. Humans could know God's works through its operations, to be had through the senses. Words are not "reliable signs of things." Rather, things provide "the only reliable criteria for shaping words properly" (Bono, pp. 218–220). The "secrets" of nature can be discovered initially through the collection of sense data and through controlled experiments. Simple data collection is insufficient, however. Careful creation of axioms and an attempt to understand the relationship of diverse things to each other would allow the book of nature to be understood.

Increasingly the observations of particulars and the positive valuation of individual experience gained credibility as a way of knowing the natural world. Individual experience and observation could be used in a variety of ways—the investigation of plants and animals, the gathering and study of objects both natural and fabricated in collections, or the dissection of human bodies. Individuals from a variety of backgrounds undertook to discover the "secrets" of nature, sometimes characterizing their pursuit as a kind of hunt. Perhaps, as one scholar has suggested, a traditional view of nature—as an inviolable, feminine entity to be protected from curiosity and aggressive exploration—declined.

Especially from the late sixteenth century investigators began to construct special kinds of individual experiences known as experiments. Experimentation developed as a great variety of practices designed to test and validate knowledge claims about the natural world. The experimenters were compelled to defend their methods against the Aristotelians. The Aristotelian term common experience referred to experience agreed upon by everyone. In contrast to the evident and universal premises of Aristotelian experience, experimenters claimed knowledge as a result of specialized, contrived experience using often complex apparatus or instrumentation. Much investigation in the history of science has been devoted to analyzing specific experiments to understand what was done, how the experiment was taken to verify particular claims about the natural world, and the ways in which the experiment was "legitimated." Often in the early modern era the reports of reliable "witnesses" lent credibility to the claims of the experimenter.

An important development was the application of mathematics to physical phenomena. This took many forms, from Galileo's analysis of balls rolling down inclined planes to Isaac Newton's (1642–1727) experiments in geometric optics. The new "physico-mathematics" of the seventeenth century rejected Aristotelian assumptions that made mathematics a self-referential discipline irrelevant to the material world and physics nonmathematical. It also either implicitly or explicitly assumed that nature itself was in some way mathematical. Descartes removed mind and spirit from the physical world and defined physical matter as extension. If the world comprised geometric extension, it could be understood by analyzing the mathematical relationships within it.

Descartes and the Laws of Nature

Descartes developed a view of nature and its workings called "the mechanical philosophy." For Descartes the world consisted of particles of matter that move whenever necessity forces them to move. Matter was extension in three dimensions. Natural philosophy consisted of describing the mechanisms of moving particles as they produced all the variable phenomena of nature. The universe was a plenum. Motion was possible because the entire mass of matter moved together. The universe consisted of a huge number of immense particle whirlpools called vortices. Particulate matter in motion explained all phenomena in nature. The mechanical philosophy developed by Descartes was highly influential. Although Descartes's successors modified the particulars of his system, it dominated European thought by the end of the seventeenth century.

Descartes first formulated physical laws that could be expressed mathematically and that were valid for all physical phenomena. Appearing in chapter seven of The World (1629–1633), they concerned inertia, collusion, and a law stating that particles of matter tended to move in a straight line. Later philosophers, such as Christiaan Huygens (1629–1695) and Gottfried Wilhelm Leibniz (1646–1716), criticized some of Descartes's specific conclusions but continued to describe the physical world in terms of laws that governed matter in motion. Newton's Philosophiae Naturalis Principia Mathematica (1687) included the three laws of motion that laid the foundation for classical physics. Newton's laws described the motion of bodies and the mathematical relationships between the forces that governed those motions.

In the eighteenth century, the "Age of Enlightenment" as the German philosopher Immanuel Kant (1724–1804) first called it, the notion prevailed that a scientific revolution had occurred in the prior century and that it was ongoing. The two key words of the Enlightenment were "reason" and "nature." The laws of reason had become synonymous with the laws of nature. Experimentation had become the way of reasoning about nature. Enlightenment philosophers and the public alike made Newton into a hero. They attempted to find further natural laws that would predict natural events completely and accurately. They sought greater determinism in nature. Although they did not fully succeed, most Enlightenment natural philosophers believed that experiment would continue to augment the progress that had occurred in understanding the natural world.