Galileo’s Daughter: A Drama of Science, Faith and Love. Dava Sobel

Чтение книги онлайн.

СКАЧАТЬ by a friend of mine, a priest who is very fond of you,’ the painter Ludovico Cardi da Cigoli warned Galileo, ‘that a certain crowd of ill-disposed men envious of your virtue and merits met at the house of the archbishop there [in Florence] and put their heads together in a mad quest for any means by which they could damage you, either with regard to the motion of the earth or otherwise. One of them wished to have a preacher state from the pulpit that you were asserting outlandish things. The priest, having perceived the animosity against you, replied as a good Christian and a religious man ought to do. Now I write this to you so that your eyes will be open to such envy and malice on the part of that sort of evildoers.’

      These gathering storms may have confirmed Galileo’s decision to cloister his daughters in the protective environment of a convent, for during the same period he wrote the letters that set the placement process in motion.

      He insisted the girls stay together, despite the frowning of the Florentine Sacred Congregation of Bishops and Regulars on the question of admitting two siblings into the same convent. Although Galileo did not set down his reasons for his wish, he may well have seen Livia already displaying the morbid tendency to melancholy and withdrawal that would shade her adult personality. Without her sunny elder sister to counteract those dark moods, what would become of her? No other Italian city, Galileo learned, opposed the entry of natural sisters into the same monastery, but he would not send the girls to another city. He preferred to keep them close by, even if that meant seeking special dispensations.

      ‘In answer to your letter concerning your daughters’ claustration,’ Francesco Maria Cardinal del Monte wrote to Galileo in December of 1611,

      I had fully understood that you did not wish them to take the veil immediately, but that you wished them to be received on the understanding that they were to assume the religious habit as soon as they had reached the canonical age. But, as I have written to you before, even this is not allowed, for many reasons: in particular, that it might give rise to the exercise of undue influence by those who wished the young persons to take the veil for reasons of their own. This rule is never broken, and never will be, by the Sacred Congregation. When they have reached the canonical age, they may be accepted with the ordinary dowry, unless the sisterhood already has the prescribed number; if such be the case, it will be necessary to double the dowry. Vacancies may not be filled up by anticipation under severe penalties, that of deprivation for the Abbess in particular, as you may see in a Decretal of Pope Clement of the year 1604.

      It could never be done, but it happened all the time, as Galileo was well aware. If Cardinal del Monte, who had finessed Galileo’s first teaching appointment at Pisa, proved unwilling or unable to get the two girls into one convent before either of them turned sixteen, then some other contact might yet intervene.

      As he neared completion of his treatise on floating bodies, Galileo penned an explanation to the grand duke and the general public as to why his new book concerned bodies in water, instead of continuing the great chain of astronomical discoveries trumpeted in The Starry Messenger. Lest anyone think he had dropped his celestial observations or pursued them too slowly, he could account for his time. ‘A delay has been caused not merely by the discoveries of three-bodied Saturn and those changes of shape by Venus resembling the moon’s, along with consequences that follow thereon,’ Galileo wrote in the introduction, ‘but also by the investigation of the times of revolution around Jupiter of each of the four Medicean planets, which I managed in April of the past year, 1611, while I was at Rome…I add to these things the observation of some dark spots that are seen in the Sun’s body…Continued observations have finally assured me that such spots are…carried around by rotation of the Sun itself, which completes its period in about a lunar month – a great event, and even greater for its consequences.’

      Thus Bodies in Water not only challenged Artistotelian physics on the behaviour of submerged or floating objects but also defaced the perfect body of the Sun. Galileo further flouted academic tradition by writing Bodies in Water in Italian, instead of the Latin lingua franca that enabled the European community of scholars to communicate among themselves.

      ‘I wrote in the colloquial tongue because I must have everyone able to read it,’ Galileo explained – meaning the shipwrights he admired at the Venetian Arsenale, the glassblowers of Murano, the lens grinders, the instrument makers, and all the curious compatriots who attended his public lectures. ‘I am induced to do this by seeing how young men are sent through the universities at random to be made physicians, philosophers, and so on; thus many of them are committed to professions for which they are unsuited, while other men who would be fitted for these are taken up by family cares and other occupations remote from literature…Now I want them to see that just as Nature has given to them, as well as to philosophers, eyes with which to see her works, so she has also given them brains capable of penetrating and understanding them.’

      Galileo’s behaviour enraged and insulted his fellow philosophers – especially those, like Ludovico delle Colombe of the Florentine Academy, who had tussled with him in public and lost. Colombe declared himself ‘anti-Galileo’ in response to Galileo’s anti-Aristotelian stance. Supporters of Galileo, in turn, took up the title ‘Galileists’ and further deflated Colombe’s flimsy philosophy by playing derisively on his name. Since colombe means ‘doves’ in Italian, they dubbed Galileo’s critics ‘the pigeon league’.

       [V] In the very face of the Sun

      IT IS DIFFICULT TODAY – from a vantage point of insignificance on this small planet of an ordinary star set along a spiral arm of one galaxy among billions in an infinite cosmos – to see the Earth as the centre of the universe. Yet that is where Galileo found it.

      The cosmology of the sixteenth and seventeenth centuries, founded on the fourth-century-BC teachings of Aristotle and refined by the second-century Greek astronomer Claudius Ptolemy, made Earth the immobile hub. Around it, the Sun, the Moon, the five planets and all the stars spun eternally, carried in perfectly circular paths by the motions of nested crystalline celestial spheres. This heavenly machinery, like the gearwork of a great clock, turned day to night and back to day again.

      In 1543, however, the Polish cleric Nicolaus Copernicus flung the Earth from its central position into orbit about the Sun, in his book On the Revolutions of the Heavenly Spheres, or De revolutionibus, as it is usually called. By imagining the Earth to turn on its own axis once a day, and travel around the Sun once a year, Copernicus rationalised the motions of the heavens. He saved the enormous Sun the trouble of traipsing all the way around the smaller Earth from morning till evening. Likewise the vast distant realm of the stars could now lie still, instead of having to wheel overhead even more rapidly than the Sun every single day. Copernicus also called the planets to order, relieving those bodies of the need to coordinate their relatively slow motion towards the east over long periods of time (Jupiter takes twelve years to traverse the twelve constellations of the zodiac, Saturn thirty) with their speedy westwards day trips around the Earth. Copernicus could even explain the way Mars, for example, occasionally reversed its course, drifting backwards (westwards) against the background of the stars for months at a time, as the logical consequence of heliocentrism: the Earth occupied an inside track among the paths of the planets – third from the Sun, as opposed to Mars’s fourth position – and could thus overtake the slower, more distant Mars every couple of years.

      Copernicus, who studied astronomy and mathematics at the University of Cracow, medicine for a while in Padua and canon law in Bologna and Ferrara, devoted most of his life to cosmology, thanks to nepotism. When he returned to Poland from his studies in Italy at the age of thirty, his uncle, a bishop, helped secure Copernicus a lifetime appointment as a canon at the cathedral of Frombork. Serving forty years in that ‘most remote corner of the Earth’, with manageable duties and a comfortable pension, Copernicus created an alternative СКАЧАТЬ