Studies On The Exploration Of Magnetic Phenomena In West In The Late16th And Early17th Centuries

The exploration of the phenomena of magnet flourished in the late16thand early17thcenturies, having Gilbert’s De Magnete as its peak. The research during thisperiod established the foundation for magnetism and electricity, while there is nomonograph of the exploration of the magnetic phenomena in west in the late16thand early17thcenturies yet.This dissertation has made use of a large quantity of original materials in kinds ofdatabases, and bases the research on the research achievements from the seventiesand the eighties of last century. Through a detailed and deep perspective of therelationship between man and natural phenomena, this dissertation studies theinvestigation on magnetic phenomena in the early modern Europe. The mainachievements are as follows.The second chapter discusses the reformation of the experimental tradition ofnatural magic, centering on Porta’s experimental studies on magnet. Because of thefruitless of scholastic contemplation, the scholars in late renaissance realized thatman faced the phenomena of nature only, and the traditional experiments in naturalmagic were then changed under this reflection. This chapter shows some importantnew characters in Porta’s experiments by comparing the magnetic experimentalresearch of Porta with that of Peregrinus. This chapter further argues that thereflection and changes are on the methods, not on the view of nature yet; and givesan alternative explanation of the “Janus-faced” problem. The third chapter studies on an item of knowledge that a loadstone rubbed withgarlic does not attract iron. This chapter collects the relative materials, and arguesalthough this knowledge looks absurd, it came from the explanation of the folk tothe phenomenon of loadstone repelling iron. This chapter compares this knowledgewith those in other ancient areas, and with the early cognition of static electricityrepulsion. The static electricity repulsion offers an important contrast. Interestinglythe observers didn’t recognize the repulsion of static electricity at first. This chapterdeems that a possible reason is that in the western culture there was a rejection ofthe fact that the things of sympathy can also repel one another.To test all the knowledge from ancient is the necessary stage of the coming intobeing of modern science. It shows that modern science roots in west civilization. Incountries where modern science was transplanted, there was no such stage oftesting all the ancient knowledge. The knowledge that a loadstone rubbed with garlicdoes not attract iron is a good example through which we can study the differentattitudes of the scholars of early modern west toward an item of ancient knowledge.This chapter then exposes the chaos of this stage, and points out that it bases on theendeavor of the scholars of testing the old knowledge that Gilbert could furtherestablish his philosophy of magnetism.The fourth chapter studies Gilbert’s experiments and theories on repulsion ofmagnet, and compares these experiments and theories with those of the scholarsbefore Gilbert. It discusses the position of magnetic movement of repulsion in hismagnetic theories and why he explained it in this way. It points out that Gilbert wasone of the minorities who considered that there was no dissimilitude or other thingslike that in loadstone, and the movement of repulsion was then reduced to awarming-up movement before coition by him. Being different from formerresearchers, it argues that Gilbert’s understanding of loadstone repulsion rooted inexperiments while his theory of repulsion was affected by ristotle’s philosophy ofteleology. The experiment of chasing floating loadstone is his main source oftheories of repulsion, but there is a serious problem hiding in this experiment. The fifth chapter studies on the history of magnetic attraction and electricattraction from having same principle to having different principles. Differing fromformer opinion that the differentiation of the two attractions is because of thediscovery of kinds of electric bodies, this chapter argues that the main reason is thediscovery of mutual action of magnetic bodies. At the time of Cardan, scholars hadjust known that magnetic bodies had mutual action, while they still believed thatamber’s attraction was in one way. So it is hard to explain mutual action and oneway action in one principle. In early modern times, there were three ways to classifythe two attractions, in material and immaterial separately, both in material, andboth in immaterial. Gilbert took the first way, and he believed that the principle ofmagnetic attraction was form. This chapter considers that Gilbert’s theory of form isan important reasoned theory of action at a distance.The sixth chapter studies the origin of Gilbert’s terrella. William Gilbert made ananalogy between spherical loadstone and the earth, calling it terrella. Terrella is themost important contribution of Gilbert. Three centuries before Gilbert, Peregrinushad considered spherical loadstone bore in itself the likeness of the heavens. Itdiscusses about the significance of Peregrinus’s spherical loadstone, and points outthat it had already contained an idea of explaining of the diurnal motion of theheavens by natural force. It then analyses the main sources of Gilbert’s terrella, anddiscusses Gilbert’s explanation of the force of earth’s diurnal motion.The seventh chapter discusses Gilbert’s explanations of the movement of thecelestial bodies of magnet force, and points out that while Gilbert was not the firstto conceive this thought, he proved it systematically through the rotation of magnetand the action of magnet for the first time. This chapter analyses Kepler’semployment of Gilbert’s explanations of the movement of the celestial bodies ofmagnet force, and points out Gilbert’s work brought this thought from a simple ideainto a serious explanation and settled the foundation for Kepler’s physical astronomy.This chapter also points out that Gilbert used logic in proving the daily revolution ofthe earth, while this has not been noticed by historians. Gilbert’s argument may not be rigorous, but if we notice his logic and his endeavor to resolve this problem in theboundary of nature, we will not assume that he had to appeal to animation.The eighth chapter sums up the whole dissertation and considers that the studyof philosophy of magnetism in late16thand early17thcenturies is not propelled bynew discoveries themselves, but by the perceptions of scholars of new and oldphenomena of magnet.