Galileo's Daughter: A Historical Memoir of Science, Faith, and Love
by dava sobel
walker and company, 432 pages, $27

The first two terms of Dava Sobel’s subtitle—science and faith—inevitably suggest conflicts to us moderns. Yet, for the preeminent scientists of the seventeenth century—Galileo, Pascal, Descartes, Newton, men of deep faith all—there seems not to have been any. In fact it was Galileo’s conviction that the truths of nature were revealed by God that drove him to establish the sun-centered theory of the universe despite fierce opposition from influential quarters. Of course, Galileo’s detractors, including religious figures such as Pope Urban VIII, were also deeply learned, as this gracefully written book makes clear. The conflict was not between darkness and light; Galileo’s opponents understood perfectly well what he was saying. What was at stake, in Dava Sobel’s words, was “the most stunning reversal in perception ever to have jarred intelligent thought: We are not the center of the universe. The immobility of our world is an illusion. We spin. We speed through space. We circle the Sun. We live on a wandering star.”

All these issues and personalities have been laid out in other works devoted to Galileo. Yet as in her immensely popular Longitude, a gripping account of eighteenth-century scientific invention in England, Sobel brings a fresh angle to her subject that makes it come alive for the ordinary reader. Here she interweaves into a story of Galileo’s public life excerpts from the 124 surviving letters from his daughter. These letters date from precisely the period, 1623 to 1633, during which Galileo published his Dialogue on Two Chief World Systems and found himself, at seventy years of age, drawn before the Holy Office of the Inquisition in Rome to defend himself against the charge of heresy. His daughter, Suor Maria Celeste, was a deeply religious young woman who entered the Poor Clares convent at age thirteen and remained cloistered the rest of her life. Yet after a fashion, her letters provide an earthly counterpoint to her father’s search of the heavens. Galileo’s side of the correspondence with his daughter was probably destroyed by the mother abbess after Maria Celeste’s death for fear of harboring the writings of a “vehemently suspected heretic.” 

The letters are about love—the third term of Sobel’s subtitle, and again we must escape modern prejudices. This is not love across a crowded room, on some enchanted evening, the inspiration of a moment. The love concerns the most abiding bonds of affection between a father and a daughter. Maria Celeste was her father’s confidant and most steadfast supporter—she chose her name, Sobel tells us, as a gesture acknowledging her father’s fascination with the heavens. Her letters testify to her absolute devotion to him and her conviction that his work was important and provided evidence of God’s will. 

While the Tuscan ambassador in Rome described Galileo as “more dead than alive” after his questioning by the Holy Office, she advised her father in the same month of April 1633: “The only thing for you to do now is to guard your good spirits, taking care not to jeopardize your health with excessive worry, but to direct your thoughts and hopes to God, Who, like a tender, loving father, never abandons those who confide in Him and appeal to Him for help in time of need.” After reading the Holy Office’s sentence, she took upon herself one of her father’s penances, the recitation of the seven penitential psalms on her knees once a week for three years. 

Baptized Virginia at her birth in 1600, she was the eldest of three children of Galileo by Marina Gamba of Venice. According to Sobel, it was the custom of scholars in the period not to marry; and though Galileo acknowledged his children, Marina’s lineage seems to have ruled out marriage to his mistress. Once Galileo settled in Florence as “Philosopher and Mathematician” to the dukes of Tuscany, the demographics (there were more women than men in Florence) and his daughters’ illegitimacy seem to have ruled out marriages commensurate with the family’s status. Already by 1611, Galileo had begun accumulating enemies among academics because of his anti-Aristotelian views. It was this animus, Sobel writes, that led Galileo to settle his two daughters in a convent, “a safer environment than he could provide for them.” 

The attention to detail that made Longitude so striking is here supplied not by Sobel but by Maria Celeste, who writes of the minutiae of convent life: how she prepared medicines from rosemary leaves for her father in the convent apothecary; or how she took care of domestic work as though she were living at home with him—sewing table linens for his frequent journeys or bleaching the white collars that can be seen gracing his face in portraits. There is frequent mention of the broad beans, orange trees, grapes, pears, and other products of Galileo’s garden, over all of which she managed to keep watch from behind convent walls. 

Indeed, food and the desire for a modicum of earthly comfort—a cell of one’s own, as it were—recur constantly in these letters. The gratitude for melons sent, the presentation of baked pears for her father on a feast day underline the exiguousness of life in the convent. Indeed, during the plague that ravaged Italy during these years, the nuns in the convent survived without a single casualty—there was apparently not enough grain in their stores to entice the disease—bearing rats. 

Suor Arcangela, Maria Celeste’s younger sister in the convent, apparently did not acquiesce in her poverty so readily. Maria Celeste writes that her sister’s eccentric nature is so very different from her own that “it pays for me to acquiesce to her in many things, in order to be able to live in the kind of peace and unity befitting the intense love we bear each other.” Twentieth-century readers may find such sentiments unworthy, testimony only to the obligations of poverty and obedience.

Yet Galileo also had strong bonds of affection among those who were not poor or subservient—his friends and defenders had wealth and power to lose by coming to his defense. Galileo resided for a time with Archbishop Ascanio Piccolomini of Siena; the archbishop, rather than holding him prisoner as a confessed heretic, instead provided the stimulus for Galileo’s last work, Two New Sciences. Galileo could also count among his allies his patron, Ferdinando II, Grand Duke of Tuscany, and Francesco Cardinal Barberini, a favorite nephew of Pope Urban whom Galileo had guided through his doctoral studies at Pisa. Barberini tried to protect his teacher at first, and ultimately was one of three (out of ten) inquisitors who did not sign the edict against him. Another pupil, Vincenzio Viviani, even succeeded in having his master’s papers published, without the forbidden Dialogue, in 1656. 

The story Sobel tells caused me to ponder whether such love can exist absent a faith in the immutability of the heavens. In calling this portrait of Galileo and his daughter an “historical memoir,” Sobel suggests the erosion that has occurred when love has no stronger grounding than the corrupt sublunary spheres. 

Elizabeth Powers is coeditor, with Amy Mandelker, of Pilgrim Souls: A Collection of Spiritual Autobiographies (Simon & Schuster).