Philosophy in the period immediately after Aristotle is sometimes thought to be marked by the decline of natural philosophy and philosophical disinterest in contemporary achievements in the sciences. But in one area at least, the early third century B.C.E. was a time of productive interaction between such disparate fields as epistemology, physics and geometry. Debates between the sceptics and the dogmatic philosophical schools focus on epistemological problems about the possibility of self-evident appearances, but there is evidence from Euclid's day of (...) a quite different response. The sceptical challenge provoked the development of theories explaining error formation, showing how illusions can be studied systematically and are subject to prediction. Such theories do not legitimate claims about the nature of the underlying entities perceived, but provide justification for forming expectations about future perceptions. While it overtly focuses on purely geometrical considerations, the Euclidean model of optics nonetheless provides support for certain views about the nature of vision and the physics of light. Moreover, by offering a model in which the image received is not thought to be a perspicuous mirroring of the object seen, Euclid may have helped promote a view of perception as something reconstructed from information received, not as a mere form transferred into the eye. The ancient sceptic may indeed have fulfilled his promise to promote inquiry by focusing attention on problems that escape the attention of a hasty theorist. (shrink)

By explaining how to sire multicolored horses, produce nuts without shells, and create an egg the size of a human head, Giambattista Della Porta's Natural Magic (1559) conveys a fascination with tricks and illusions that makes it a work difficult for historians of science to take seriously. Yet, according to William Eamon, it is in the "how-to" books written by medieval alchemists, magicians, and artisans that modern science has its roots. These compilations of recipes on everything from parlor tricks through (...) medical remedies to wool-dyeing fascinated medieval intellectuals because they promised access to esoteric "secrets of nature." In closely examining this rich but little-known source of literature, Eamon reveals that printing technology and popular culture had as great, if not stronger, an impact on early modern science as did the traditional academic disciplines.By explaining how to sire multicolored horses, produce nuts without shells, and create an egg the size of a human head, Giambattista Della Porta's Natural Magic (1559) conveys a fascination with tricks and illusions that makes it a work difficult for historians of science to take seriously. Yet, according to William Eamon, it is in the "how-to" books written by medieval alchemists, magicians, and artisans that modern science has its roots. These compilations of recipes on everything from parlor tricks through medical remedies to wool-dyeing fascinated medieval intellectuals because they promised access to esoteric "secrets of nature." In closely examining this rich but little-known source of literature, Eamon reveals that printing technology and popular culture had as great, if not stronger, an impact on early modernscience as did the traditional academic disciplines. (shrink)

Torporley's ‘Congestor analyticus’, completed in 1627 in the library of the Earl of Northumberland at Petworth, was seen by Rigaud in the 1830s among the mathematical manuscript collection of the Earl of Macclesfield. Torporley's additional copy of the introductory part, preserved at Sion College, has been used for the present report. Torporley's prime objective was the presentation of some of Harriot's work. His first example concerns a classical problem in number theory. The complete solution, by an inductive process based on (...) tables of differences, is given in a few folios of the British Library collection of Harriot manuscripts. Torporley's transcription and commentary contrast forcibly today with the immediate illuminating impact of Harriot's original. (shrink)