Transcript The Scientific Revolution

The “New Science”
of the Seventeenth Century
The Changing Heavens:
Revolutions in Astronomy
Revolution or Evolution?
• Historians have long challenged the idea
of a single “Scientific Revolution”
• Most scholars agree that the “new
science” of the seventeenth century was
the culmination of centuries of advances
• Still, it is impossible to deny that the
seventeenth century witnessed an
increase in knowledge, new methods, and
growth of the scientific community
A paradigm shift?
• In his pioneering 1962
work Kuhn argued that
the Scientific Revolution
represented a paradigm
shift that allowed certain
ideas to become
“thinkable” – not just an
inevitable outcome of the
progress of science
Medieval Universities
• In the Middle Ages, natural philosophers
saw nature as a book in which they could
read the mind of God
• Medieval science “stood on the shoulders
of giants” and scholars believed that all
human knowledge had been understood
by the ancient philosophers
• The rediscovery of Aristotle’s writings in
the Twelfth and Thirteenth centuries led to
a renewed interest in science
St. Thomas Aquinas (1225-1274)
• Reconciliation of faith and
reason
• Systematization of
Aristotle’s thought with
Christian doctrine
• Gives the church almost
full control over
intellectual life
Humanism and science
• Many of the most famous humanists were
not interested in ‘science’ per se – they
were interested in eloquence and morals
• But their interest in classical antiquity also
pushed them to study the texts of ancient
philosophers and mathematicians more
closely.
• Neoplatonism was influential, as was the
mechanistic theories of the Greek
physicist Archimedes
New methods of observation
• Renaissance artists were keen on
observation and description of the world
around them ‘the mind of a painter should
be like a mirror’
• For example, Da Vinci encourages
dissection of corpses; renaissance art and
architecture works with geometry and light
• These artists develop tools and formulas
that can be extended to the study of
astronomy
Astronomy
• Aristotle and Ptolemy were the two main
sources for astronomy – they supported
the long-held idea that the sun, stars, and
the planets revolved around the earth
• The earth-centred universe was important
for a couple of reasons:
– It was the foundation of theological
conceptions of the universe
– On a more practical level, it was how the year
was measured and the calendar was devised
The Ptolmaic universe
• Aristotle had described an orderly cosmos
• Things could change on earth, but the
heavens were thought to be unchanging,
moving in perfect circles
• People had noticed inconsistencies in this
theory – simple observation of planets
showed this
• The mathematician Ptolemy (85-165) had
developed complicated formulas to explain
the irregularities
Ptolemy’s universe
Nicholas Copernicus (1473-1543)
• Based on mathematical formulas, he
suggested that the earth and the planets
revolved around the sun
• This would solve many of the problems with
the calendar and avoid the complicated and
mathematical formulas upon which
Ptolemy’s system relied
• Copernicus did not want to challenge the
church or ancient authorities
• He did not base his theory on observation
Copernicus
• Copernicus did not
have a system of
physics that could
explain an earth in
motion
• His mathematical
ideas were published
just before his death in
On the Revolution of
the Heavenly Spheres
(1543)
Observing the heavens
• The work of Copernicus was all theoretical
• It took time for others to take up his
theories and to prove them by observation
• Tycho Brahe was a Danish nobleman who
devoted much of his life and resources to
observing the movement of the heavens
• An example of his audacity is that he
discovered a new star – an impossibility
according to Aristotle.
Tycho Brahe (1546-1601)
• Brahe was not convinced
by Copernicus – he
believed the planets
orbited the sun and that
the whole system revolved
around the earth, which
was less challenging to
contemporary ideas.
• His observations were
very accurate and formed
the basis of Kepler’s work
Johannes Kepler (1571-1630)
• He did support the
Copernican view of
the universe – with
modifications
• First, he argued that
planets revolved
around the sun in
elliptical orbits – not
the perfect circles that
both Ptolemy and
Copernicus relied on
Kepler
• His ‘Second law’ was that planets moved
at different speeds depending upon their
distance from the sun – not uniform speed
as Copernicus had suggested
• Most scientists in the 17th century rejected
this idea – but it was an integral part of the
development of Newton’s laws of gravity.
Galileo Galilei (1564-1642)
• Galileo not only set out
to prove Copernicus’
theory through
observation, but also
argued for a new
partnership between
religion and science
• Ultimately, his
argument was
unsuccessful
Tools of science: the telescope
• In 1610, Galileo procured a telescope and
began making observations of the
heavens
• He observed moons orbiting Jupiter –
which proved that the earth was not the
only planet with objects in orbit around it
• Initially, he received patronage for his
work, but it quickly brought him into
conflict with the church
Robert Bellarmine (1542-1621)
• Cardinal Bellarmine, one of
the leading Jesuit scholars,
led the attack on Galileo
• Argued against
Copernicanism and had his
work included in the Index of
Prohibited Books
• In effect, he managed to
silence Galileo for the time
being
Galileo’s Trial
• After Bellarmine’s death, Galileo again
began to promote helicentrism
• The church charged him with heresy, both
for promoting Copernicus and for
offending his patron Maffeo Barberini, who
had become Pope Urban VII
• He was threatened with excommunication
and death and he recanted his beliefs
• In secret, he continued to work on his
theories until his death
Conclusion
• While the Catholic Church continued to
play down the changes in astronomy,
scientists across Europe continued to
rethink the Cosmos and humans’ place in
it
• The advances in astronomy laid the
foundation for a more thorough-going
overhaul of scientific methods, which we
will discuss next time