Don't fail to be as critical of
your own theories as you are
of the theories of others . . .
. . . because Nature doesn't care what you think; and nature didn't care about
Galileo's theory of the tides.
What lessons
might we learn...
Galileo Galilei
FAQ
Don't be mean to people.
(cf. Or. Grassi & Chr. Scheiner)
from Galileo's Life
and Troubles?
"If Galileo had known how to stay on friendly terms with the Roman College, he would be enjoying fame in the world, he would not have had any misfortunes, and he would be able to write freely about anything, even the motion of the earth." Grienberger (reported), Heilbron, 312.
Galileo Galilei
(1564-1642)
The Myth
James Lattis
Univ. of Wisconsin-Madison
Did the Inquisition...
The Telescope...
Torture/burn/excommunicate (etc.) Galileo?
Did Galileo Invent It?
(Not to be modified or redistributed without consent of the author.)
Did the Inquisition...
Clavius, Sphaera (1611)
. . . not long ago a certain instrument was brought from Belgium . . . This instrument shows many more stars in the firmament . . . and when the moon is a crescent or half full, it appears so remarkably fractured and rough that I cannot marvel enough that there is such unevenness in the lunar body. Consult the reliable little book by Galileo Galilei, printed at Venice in 1610 and called Sidereal Messenger, which describes the various observations of the stars made by him.
Far from the least important . . . is that Venus receives its light from the sun as does the moon, so that sometimes it appears to be more like a crescent, sometimes less, according to its distance from the sun. At Rome I have observed this in the presence of others more than once. Saturn has joined to it two smaller stars, one on the east, the other on the west. Finally, Jupiter has four roving stars, which vary their places in a remarkable way both among themselves and with respect to Jupiter--as Galileo Galilei carefully and accurately describes.
Since things are thus, astronomers ought to consider how the celestial orbs may be arranged in order to save these phenomena. (p. 75)
Did the Inquisition...
24 April 1611:
Jesuit astronomers
reply to
Card. Bellarmino
No.
They confirm
- Vast numbers of previously unseen stars
- Peculiar shape of Saturn
- Venus exhibits phases from new to full
- Lunar surface *appears* rough and irregular
- 4 objects that are not fixed stars accompany Jupiter
Condemn Galileo because of his Discoveries?
1609-1611, telescopic discoveries
1611, discoveries confirmed & praised
1616, Bellarmino restricts Copernican discussions to hypothetical
1632, Galileo publishes his Dialogo
1633, trial and condemnation
Of His Astronomical Discoveries...
Did the Inquisition...
What were the most important ones?
Condemn Galileo because of his Discoveries?
Did Galileo's Discoveries...
No.
Prove the Copernican Theory correct?
G. was already a Copernican as early as 1597, he says, but a quiet one until . . .
- Jovian Moons
- Phases of Venus
These overthrow Ptolemy/Aristotle . . .
But they leave Tycho's system intact . . .
And therefore do not prove the Copernican to be true.
Did Galileo's Critics...
Refuse to look through the telescope?
Did Galileo Blind Himself...
Looking at the Sun through his telescope?
photo credit Nasa / Goddard Space Flight Center / Reto Stöckli
Probably not.
- Thomas Harriot, England, Moon
- Simon Marius, Germany, Jovian Moons
- Christoph Scheiner, Germany, Sunspots
- Benedetto Castelli, Italy, predicted the Phases of Venus