Plate 2 from Nova Reperta
by Johannes Stradanus



In Stradanus's plate, the scholar in his study is surrounded by the new instruments of navigation, drafting, and surveying. An armillary sphere, a compass, an octant, several books, and other measuring tools sit on the table at left. In the left foreground, a lodestone floats on a raft of wood in a wine cooler. The model galleon suspended from the ceiling contrasts to the single-masted, oared Mediterranean vessel that can be seen through the window. The juxtaposition of instruments and books on the scholar's desk indicates the coming together of the hitherto generally separate traditions of practice and theory. Out of their union, the new experimental philosophy emerged.

In the seventeenth century, practitioners of this new experimental philosophy came to view themselves as purveyors of a new kind of knowledge. In the wake of their claims, broad epistemological conflicts developed over the concepts of experience and experiment. These conflicts are examined by Peter Dear and Adrian Johns, among others. The conflicts threatened the dominant Aristotelian sense of common experience as that which was acknowledged by all and therefore required no demonstration (e.g., if you drop a brick, it will fall downwards). The new experimental philosophers posited instead that truth claims were to be subject to particular experiments. Often such experiments required complex apparatus, such as the air pump, that could be constructed and manipulated only by experts. Thus the status of the experimental philosophy as philosophical knowledge was problematic; how could it be universally accepted if it relied on particular experiences and events available only to a few individual experts?

Although, in many cases, experimental philosophers exaggerated their complete break with the natural philosophy of the past, several points of difference can be identified between the new experimental philosophy and the natural philosophy of the ancient and medieval periods. The experimental philosophers sought explanations in terms of mechanisms more often than causes. Although they did not always acknowledge their debt, the methods of the experimental philosophers drew from the ways in which craftspeople manipulated natural materials. Individuals who called themselves "new philosophers" were a more diverse group than natural philosophers in the past, and they were sometimes newly arrived in the republic of letters. In addition, venues for natural philosophical practice shifted from the universities to other sites-royal courts, the new academies such as the Royal Society that emphasized experimentation, craft workshops, and even private residences. Investigators proclaimed themselves active experimenters rather than bookish contemplators, interested not in system building, but in the active collection of experience.

Their standards of proof and their modes of legitimating their knowledge also differed markedly from the kinds of investigations that had come before. They couched their proofs in the terms of individual narratives of experimental practice rather than general logical demonstration. Thomas Sprat (1635-1713) in The History of the Royal Society (1667) laid out the correct comportment of the natural philosopher and the ideal natural philosophical community. Although very different as individuals, Galileo Galilei (1564-1624), Robert Boyle (1627-91), and, eventually, Isaac Newton (1643-1727), became model natural philosophers for their contemporaries. All three viewed instruments as part of nature, and all used mathematical arguments to make truth claims in natural philosophical and physical knowledge. Not all seventeenth-century philosophers accepted the epistemological claims of these natural philosophers as unproblematic, however. Thomas Hobbes (1588-1679) disputed them outright, while individuals such as Blaise Pascal (1623-1662) conducted natural philosophical investigation that combined older modes of legitimating knowledge with the use of philosophical instruments and mechanical theorizing.

The Scientific Revolution is often rightly viewed as a period of great theoretical change in natural philosophy. But it would be a mistake to view it solely in this way; it can also be seen as a period of transformation in attitudes to experience and to practice. In the sixteenth and seventeenth centuries, practices involving the investigation of nature changed, and the kinds of people who pursued such investigations expanded. Natural knowledge became a resource by which a great variety of individuals made claims to authority and intellectual legitimacy. As "experiment" came to replace "experience," knowledge of nature, based upon the new experimental philosophy, came to occupy a central place in early modern culture.