Speaker 1: Welcome to brain Stuff, a production of iHeart Radio, Hey
Speaker 1: brain Stuff Lauren Bogelbaum here today. Italian astronomer, physicist, and
Speaker 1: author Galileo Galilei, who lived from fifteen sixty four to
Speaker 1: sixteen forty two, might be most famous for having been
Speaker 1: put on trial for heresy by the Roman Inquisition in
Speaker 1: sixteen thirty three. That event has come to symbolize the
Speaker 1: conflict between adherence to religious dogma and the intellectual freedom
Speaker 1: required by science. Galileo's trouble with authorities actually stemmed not
Speaker 1: from his own work, but from his advocacy of Polish
Speaker 1: astronomer Nicolas Copernicus's heliocentric theory that the Sun, not the Earth,
Speaker 1: was the object around which the planets revolved. Galileo was
Speaker 1: forced to renounce those views to avoid torture and execution,
Speaker 1: and had to spend the last years of his life
Speaker 1: under house arrest. Even so, Galileo ultimately won the argument.
Speaker 1: Three and a half centuries later, Pope John Paul Second
Speaker 1: gave a speech in which he not only said that
Speaker 1: the Church's persecution of Galileo had been a mistake, but
Speaker 1: also praised him as a brilliant mind who quote practically
Speaker 1: invented the experimental method. But all of that bruhaha, isn't
Speaker 1: the most important thing about Galileo, a scientific giant whose
Speaker 1: discoveries forever changed humans views of both the cosmos and
Speaker 1: the physical world in which we live, and helped establish
Speaker 1: the way in which modern scientists do science. He also
Speaker 1: became one of the first celebrities scientist authors, whose sixteen
Speaker 1: ten book Starry Messenger became a sensation. We spoke by
Speaker 1: email with Paula Finland, the Ubaldo Pierratti, Professor of Italian
Speaker 1: history and co director of the Patrick Soupy Center for
Speaker 1: the History and Philosophy of Science at Stanford University. She
Speaker 1: said Galileo is an interesting example of a versatile Renaissance mind.
Speaker 1: He loves literature, art and music as well as science.
Speaker 1: He knows how to draw, and he certainly knows how
Speaker 1: to fight with eloquence. He's fascinated with how things work
Speaker 1: and visits artisans to know more. I see him as
Speaker 1: one of the culminating products of the Renaissance, living in
Speaker 1: the age of the Reformation. Yet what he does with
Speaker 1: his knowledge launches a new age of science and observation.
Speaker 1: Galileo was born in Pisa, Italy, in fifteen sixty four,
Speaker 1: one of six or seven children of a musician named
Speaker 1: Vincenzo Galilei. In Galileo's youth, his family moved to Florence.
Speaker 1: After getting his early education at a monastery. Galileo was
Speaker 1: sent by his father in fifteen eighty one to the
Speaker 1: University of Pisa, where he was supposed to earn a
Speaker 1: medical degree, but Galileo didn't have much interest in healing
Speaker 1: the human body. Instead, he was curious about the world
Speaker 1: around him and started physics experiments, some of them challenging
Speaker 1: the views of the classical Greek philosopher Aristotle. In fifteen
Speaker 1: eighty five, he left the university without earning a degree
Speaker 1: and began teaching mathematics, another of his interests. Eventually, his
Speaker 1: reputation grew so much that in fifteen eighty nine he
Speaker 1: was invited back to the university to head the math department.
Speaker 1: In fifteen ninety two, Galileo moved to Venice and took
Speaker 1: a better paying post at the University of Padua, where
Speaker 1: he spent the next eighteen years teaching math in astronomy.
Speaker 1: During that time, he began a relationship with a woman
Speaker 1: named Marina Gamba, with whom he eventually had two daughters
Speaker 1: and a son. In sixteen o nine, while still at
Speaker 1: the university, Galileo heard about a Dutchman who had visited
Speaker 1: Venice and showed off a new invention, the telescope. Galileo
Speaker 1: decided to make his own version and taught himself how
Speaker 1: to grind lenses to an even higher magnification. But we
Speaker 1: also spoke by email with Alan Hirschfeld, a physics professor
Speaker 1: and director of the U Mass Dartmouth Observatory and the
Speaker 1: author of the book Starlight Detectives, How Astronomers, inventors, and
Speaker 1: Eccentrics Discovered the modern Universe. He said he was an
Speaker 1: excellent craftsman who read descriptions of the instrument and made
Speaker 1: the most powerful telescopes at the time. He could see
Speaker 1: what others could not, and therefore his observations were groundbreaking.
Speaker 1: Perhaps the most important of Galileo's astronomical discoveries were his
Speaker 1: revelations about the Moon's topography and how its mountains, valleys,
Speaker 1: and plains are comparable to those on Earth. Hirschfeld explained,
Speaker 1: it's a material world in space, not some special celestial
Speaker 1: body made of divine substance. Galileo's discovery of Jupiter's moons
Speaker 1: and their movement was another breakthrough. Hirschfeld said, they keep
Speaker 1: up with Jupiter as it moves, whether it moves around
Speaker 1: the Earth or around the Sun, depending on one's beliefs,
Speaker 1: but Jupiter's moons do not get left behind, as critics
Speaker 1: of Copernicus claimed our moon would if Earth were moving
Speaker 1: around the Sun. Jupiter and its moons provide a model
Speaker 1: of what the Solar System is like small bodies orbiting
Speaker 1: the larger body. Galileo also observed the Milky Way consists
Speaker 1: of stars, most of which are you faint to be
Speaker 1: seen individually by unassisted human eyes, meaning that we learned
Speaker 1: that there are more stars and indeed more cosmos out
Speaker 1: there than anyone had previously thought. He also discovered that
Speaker 1: the planet Venus has changing crescent phases. But we spoke
Speaker 1: by email with Larry Marshall, and emeritus professor of physics
Speaker 1: at Gettysburg College. He said the observation that Venus went
Speaker 1: through a full cycle of phases from new to crescent
Speaker 1: to full and back was totally incompatible with the geocentric
Speaker 1: model of the universe. It could only be explained if
Speaker 1: Venus went around the Sun in an orbit that was
Speaker 1: smaller than the Earth's orbit around the Sun, in other words,
Speaker 1: the Copernican model. Though his astronomical discoveries made him a
Speaker 1: scientific celebrity, Galileo also made important discoveries in physics, going
Speaker 1: back to his early years at the University of Pisa.
Speaker 1: For example, Galileo disproved the Greek philosopher Aristotle's belief that
Speaker 1: heavier objects fall faster than lighter ones, and instead showed
Speaker 1: that objects tend to fall at the same speed no
Speaker 1: matter what their weight or shape, which became known as
Speaker 1: the law of falling bodies. In legend, Galileo accomplished this
Speaker 1: by dropping a cannon and a musket ball from the
Speaker 1: leaning Tower of Pisa, though modern historians have cast doubt
Speaker 1: upon that story. Galileo also discovered that the time taken
Speaker 1: for a pendulum to complete complete one swing was independent
Speaker 1: of the length of the ark, which led him to
Speaker 1: create a design for pendulum clock. But his most important
Speaker 1: breakthrough may have been discovering the concept of inertia that
Speaker 1: bodies at rest tend to remain at rest, which eventually
Speaker 1: became the first of the three laws of motion described
Speaker 1: by British physicist and mathematician Isaac Newton. In the process,
Speaker 1: Galileo also helped establish the way that today's scientists do science.
Speaker 1: Hirschfeld said he fostered the paradigm of physical experiment, precise measurement,
Speaker 1: and objective observation. Let nature speak as the saying goes,
Speaker 1: as opposed to logical inference based on preconceived notions about nature.
Speaker 1: The language of nature, he wrote, is mathematical, and one
Speaker 1: must learn to understand that language. Today's episode was written
Speaker 1: by Patrick J. Tiger and produced by Tyler Playing. For
Speaker 1: more on this and lots of other weighty topics, visit
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