This paper defends a version of J. H. Randall’s thesis that modern empiricism is rooted in the Scholastic regressus method epitomized by Jacopo Zabarella in De Regressu (1578). Randall’s critics note that the empirical practice of Galileo and his contemporaries does not follow Zabarella. However, Zabarella’s account of the regressus is imprecise, which permitted an interpretation introducing empirical hypothesis testing into the framework. The discourse surrounding Galileo’s lunar observations in Sidereus Nuncius (1610) suggests that both Galileo and his interlocutors amended (...) the regressus method in this way, such that a developmental narrative links Scholastic logic to Galilean science. (shrink)

The ArgumentThe article deals with the interrelation between Galileo and the visual arts. It presents a couple of drawings from the hand of Galileo and confronts them with Viviani's report that Galileo had not only wanted to become an artist in his youth but stayed close to the field of visual arts throughout his lifetime. In the ambiance of these drawings the famous moon watercolors are not in the dark. They represent a very acute and reasonable tool to convince the (...) people who trusted images more than words. The article ends with Panofsky's argument that it was Galileo's anti-Mannerist notion of art that evoked a repulsion of Kepler's ellipses. It tries to show that it was again an aesthetical prejudice that hindered Einstein from accepting Panofsky's theory. (shrink)

the article deals with the interrelation between galileo and the visual arts. it presents a couple of drawings from the hand of galileo and confronts them with viviani's report that galileo had not only wanted to become an artist in his youth but stayed close to the field of visual arts throughout his lifetime. in the ambiance of these drawings the famous moon watercolors are not in the dark. they represent a very acute and reasonable tool to convince the people (...) who trusted images more than words. the article ends with panofsky's argument that it was galileo's anti-mannerist notion of art that evoked a repulsion of kepler's ellipses. it tries to show that it was again an aesthetical prejudice that hindered einstein from accepting panofsky's theory. (shrink)

The ArgumentIn 1612, Lodovico Cigoli completed a fresco in the Pauline chapel of the Basilica of Santa Maria Maggiore in Rome depicting Apocalypse 12: “A woman clothed with the sun, and the moon under her feet.” He showed the crescent Moon with spots, as his friend Galileo had observed with the newly invented telescope. Considerations of the orthodox view of the perfect Moon as held by philosophers have led historians to ask why this clearly imperfect Moon in a religious painting (...) raised no eyebrows. We argue that when considered in the context of biblical interpretation and the rhetoric of the Counter-Reformation, the imperfect Moon under the woman's feet was entirely consistent with traditional interpretations of Apocalypse 12. (shrink)

ArgumentA Catoptrica attributed to Euclid appears in manuscripts amongst treatises dealing with elementary astronomy. Despite this textual background, the treatise has always been read literally as a theory of mirrors, and its astronomical significance has gone unnoticed. However, optics, catoptrics, and astronomy appear strongly intermingled in sources such as, amongst others, Geminus, Theon of Smyrna, Plutarch and Cleomedes. If one compares the optical reasoning put forward in these sources to account for the formation of moonlight with arguments of Catoptrica, one (...) is able to shed new light on several principles and propositions of Catoptrica, some of which had been deemed corrupt, meaningless, and obscure. Moreover, the present analysis offers a glimpse at the context of a specific stage in the evolution of ancient catoptrics: Whether literally or by analogy, several of its results appear to have been set against a wider astronomical background, which explains the inclusion of Catoptrica in the group of texts loosely defined as “little astronomy.”. (shrink)

: Scientific observation is determined by the human sensory system, which generally relies on instruments that serve as mediators between the world and the senses. Instruments came in the shape of Heron's Dioptra, Levi Ben Gerson's Cross-staff, Egnatio Danti's Torqvetto Astronomico, Tycho's Quadrant, Galileo's Geometric Military Compass, or Kepler's Ecliptic Instrument. At the beginning of the seventeenth century, however, it was unclear how an instrument such as the telescope could be employed to acquire new information and expand knowledge about the (...) world. To exploit the telescope as a device for astronomical observations Galileo had to: 1. establish that telescopic images are not optical defects, imperfections in the eye of the observer, or illusions caused by lenses; 2. develop procedures for systematically handling errors that may occur during observation and measurement and methods of processing data. Galileo made it clear that in order to measure and interpret natural phenomena accurately, a suitable method and instrument would need to be developed. It is intriguing, therefore, to regard the Galilean telescope in this light and to discover the linkage established by Galileo among theory, method, and instrument—the telescope. Although the telescope was not invented through science, it is instructive to see how Galileo used optics to employ a theory-laden instrument for bridging the gulf between picture and scientific language, between drawing and reporting physical facts, and between merely sketching the world and actually describing it. (shrink)

It is argued that Galileo's theory of justification was a version of explanationism. Galileo's Dialogue on the Two Chief World Systems is to be read as primarily a defense of his theory of the tides. He shows how, by assuming Copernican motions, he can explain the tides, thereby justifying the endorsement of Copernicus. The crux of the argument rests on Galileo's account of explanation, which is novel in its reliance on the use of geometry. Finally, the consequences of his use (...) of geometry, and his views on the limits of knowledge, force us to conclude that if Galileo was a realist, his realism was so highly constrained as to be irrelevant. (shrink)