Galileo was born into a continent wracked
by cultural ferment and religious divisions. The late 1500s saw
the last years of the Italian Renaissance, a revival of arts and
letters that sought the recovery and reworking of classical art
and philosophy from ancient Greece and Rome. In the 15th and 16th
centuries, Renaissance Italy was a center of artistic and intellectual
ferment, a home for the great geniuses of the revived humanistic
spirit–Machiavelli, Da Vinci, Petrarch, Michelangelo, and many
more. But the popes were also enjoying the peak of their influence:
not just the leaders of the Roman Catholic Church during these
years, the popes served as secular leaders as well, controlling
much of central Italy around their seat in Rome, and the decadent
spirit of the age infected their Church. The Renaissance Popes,
a colorful group who acted as great patrons of the flourishing
artistic culture, presided over an era of corruption and worldliness
within the Church, and their personal morality brought the reputation
of the Papacy to historic lows.
By the time of Galileo's youth, the Church was purging
itself of the excesses of the Renaissance–but facing a crisis in
the north. Martin Luther, a former monk, attacked Catholicism
for having become too worldly and politically corrupt, and for
obscuring the fundamentals of Christianity with pagan elements
ranging from the cult of the saints to the adoration of the Virgin
Mary. His reforming zeal, which appealed to a notion of an original,
"purified" Christianity, set in motion the Protestant Reformation,
which split European Christianity in two. In response, Roman Catholicism
steeled itself for battle. The Catholic Counter-Reformation, called
into being by the Council of Trent, emphasized orthodoxy and fidelity
to the true Church. A new religious order, called the Jesuits,
or Society of Jesus, arose to act upon these principles, and now
stood at the vanguard of the battle with Protestant heresy. The
Counter-Reformation reinvigorated the Church, and incited a great
wave of intellectual, artistic, and religious energy. But it also
put an end to the liberality and leniency of the Renaissance; its
emphasis on religious orthodoxy, rigidly enforced by the Inquisition,
would soon clash with the emerging scientific revolution.
Galileo, with his study of astronomy, would figure at
the center of this clash. Conservative astronomers, working without
telescopes, had always ascribed to the theory of geocentricity,
which held that the earth ("geo," as in "geography" or "geology")
lay at the center of the solar system, and the sun–and the other
planets–revolved around it. Indeed, to the casual observer, it
seemed common sense that the sun "rose" in the morning and "set"
at night, in its circling pattern around the earth. Ancient authorities
like Aristotle and the Roman astronomer Ptolemy had championed
this viewpoint, and the notion also coincided with the Catholic Church's
view of the universe, which placed mankind, God's principle creation,
at the center of the cosmos. Thus buttressed by common sense,
the ancient philosophers, and the Church, geocentricity seemed
secure in its authority.
Ptolemy had worked out a geocentric system of brilliant
geometric precision–but this system of interlocking orbits grew
ever more complex as astronomers strained to make more modern observations
fit a mistaken theory, and in the 16th century, the theory began to
fall under attack. The first to question it was Nicholas Copernicus,
a Polish astronomer, whose work On the Revolution of Heavenly
Orbs (published after his death, in 1543) proposed a heliocentric
system, in which the planets–including earth–orbited the sun ("helios").
This more mathematically satisfying way of arranging the solar
system did not attract many supporters at first, since the available
data did not yet support a wholesale abandonment of Ptolemy's system.
But by the end of the 16th century astronomers like Johannes Kepler
(1571-1630) had begun to embrace it, and once Galileo began to
observe the heavens through his telescope, the fate of the Ptolemaic
system was sealed.
But so too was the fate of Galileo–for the Catholic Church,
desperately trying to hold the Protestant heresy at bay, could
not accept a scientific assault on its own theories of the universe.
The pressures of the age set in motion the historic confrontation
between religion and science, which would culminate in the Church's
disastrous trial of Galileo in 1633.