GALILEO: Heretic

By Pietro Redondi

Translated from the Italian by Raymond Rosenthal

Princeton University Press. 356 pp. $29.95

THE GREAT MARTYRS in history -- Socrates, Joan of Arc -- win us over by their dedication to noble causes. We are won all the more readily if the cause has a vital relevance for us, such as the right of untrammelled intellectual inquiry. This being so, what is the historian to do, in his need for some kind of detachment, when faced with a deeply seductive martyr? Cool and yet keenly committed, this book provides an answer.

Not of course that Galileo paid with his life. Summoned from Florence to stand trial in Rome in 1633, he was condemned by the Holy Office for averring Copernicanism, the theory that put the sun at the center of our solar system. The damning evidence was in his book of the previous year, Dialogue Concerning the Two Chief World Systems. Catholic authority had censured the views of Copernicus (d. 1543) in 1616, and in the same year Galileo had been warned to hold his tongue on the subject. Judged, therefore, to have relapsed, he was condemned to prison for life; but Pope Urban VIII intervened and had the sentence commuted to lifelong house arrest so that Galileo could return to live and work at home in Florence.

But was Galileo's trial truly the result of his endorsing the notion of a fixed sun and an orbiting earth? Pietro Redondi breaks with this time-honored verdict and, adducing a newly-discovered document (1982), rewrites the history of the case. He contends that the trouble lay in Galileo's physics, not in his astronomy; that 17th-century Catholic theology could more easily live with heliocentrism (the Copernican system) than with a physics whose atomism seemed to menace the dogma of the Eucharist, according to which bread and wine, on being consecrated by a priest, were ipso facto transubstantiated into the body and blood of Christ.

Although less than three pages long, the new document is telling. It is a secret and anonymous denunciation, lodged with the Holy Office sometime in 1624, manifestly argued by a skilled logician, and claiming that the Democritan atomism of Galileo's Il Saggiatore, issued in 1623, in effect questioned "the existence of the accidents of the bread and wine which in the Most Holy Sacrament are separated from their substance." But because the later trial record studiously avoids the real scandal, in itself too delicate and baneful, Redondi is forced to reconstruct in detail the background to the entire case. All the book's excitement is here.

The story has an eminence grise: the powerful Society of Jesus. The society's leading intellect, Father Orazio Grassi, a brilliant mathematician based at the Collegio Romano for the training of Jesuits, had published a work on comets in 1619, promptly touching off a polemic with Galileo. Rage and bitterness supervened, as well as the first hints of a possible threat to eucharistic doctrine. Galileo's Saggiatore, with its fleering ridicule of Lotario Sari (Grassi's well-known pen name) and of his old-fashioned scholasticism, was a major statement along the way. The fight, however, was not a duel: for arrayed behind them were mighty religious orders, cardinals, glittering artistocrats, fashionable men of letters and even the new (1623) Pope Urban VIII. In due course, as we shall glimpse, the blistering center of European politics, the Thirty Years War (1618-1648), would itself scorch the main combatants.

GALILEO ANIMATED a movement against the intellectual tyranny of Aristotelian scholasticism. He campaigned for "a new {scientific} language," for "the rights of research and free intellectual discussion against the prevarication of institutional culture." But he could also be very mistaken, as in his contention, in the quarrel with Grassi, that comets were a kind of optical illusion, a claim made in oblique defense of the circularity of the Copernican system (for comets do not orbit in circles). Against Galileo, the men and movement around Grassi called for a more cautious line of scientific inquiry.

The outcome of the controversy was not preordained. Papal Rome, the immediate battle ground, was a city old in the knowledge of ambition, fierce intrigue and virtuoso personal diplomacy. In the 1620s the city's brightest, richest and most worldly men, including Pope Urban, threw their weight behind Galileo. "The new philosophy was in the Curia, the university chairs, the academies, and the families of Roman high society." In short, there was a mood to humble the Society of Jesus.

But the Galileans forgot history. In 1631, the menace of triumphant Protestant armies in Northern Europe was about to draw the papacy away from France, into the Spanish Hapsburg and imperial camps. Almost overnight the cause of Catholic Europe seemed to fall into grave danger. The entire mood shifted, and suddenly a pivotal bloc of cardinals in Rome was able to exercise decisive, even intimidating, pressures on Pope Urban. At that very moment (Feb. 1632), Galileo imprudently brought out in Florence his Dialogue Concerning the Two Chief World Systems. His backers in Rome immediately sought to have the edition suppressed -- too late. In August, to silence one of their own philosophers in Prague, the Jesuits officially condemned the notion of atoms in their own teaching. And though the Florentine had strained to avoid corpuscular or particle theory in the Dialogue, Redondi argues convincingly, on the basis of strange and intriguing oddities in the trial proceedings, that Galileo in effect made a secret deal with the authorities, letting himself be accused of a lesser heresy (heliocentrism) for the sake of avoiding the dreadful charge of a major one, his challenge to the physics of the Eucharist.

Not long since, Jesuits had been disembowelled in England; and amid the savagery of the period's religious wars, they held the front line in the doctrinal battle to win Europe back to Rome. Hence their victory over Galileo figured as a moment in an epic struggle. Meanwhile, however, the humbled Urban VIII, though angry with Galileo, also saw to it that Grassi was banished from Rome, along with other key figures in the controversy.

The elegance and subtlety of this remarkable book come from Redondi's tight weaving together of personalities, anecdote, doctrine and fine points of theory. He takes hold of the two men, Galileo and Grassi, in a setting rich with all the pertinent passions of their day. The history of ideas is here brought down to earth.

Lauro Martines is professor of Renaissance history at the University of California, Los Angeles and author of "Power and Imagination: City-States in Renaissance Italy."

Jonathan Yardley is on vacation