Geocentrism Flashcards
What is the belief of the geocentric theory?
That the earth is at the center of the world
What are deferents
Deferents are crystal/glass spheres mad of quintessence that all have my bodies move on around the earth
Where are the stars located
On the outermost deferent called the celestial sphere
What accounts for the planet’s independent motion?
The planets are each on their own individual sphere
What are eccentric orbits
Eccentric orbits are off centers orbits
What are eccentrics accounted for
Eccentrics are accounted for the the varying distances of the planets from the earth(ie Venus is closer and farther away from the earth)
What are epicycles
Epicycles are a wheel upon wheel motion
What do epicycles account for
Epicycles account for the apparent backward motions of the planets
Who is the Greek philosopher who taught the geocentric theory
Hipparchus
Who is Ptolemy ?
Ptolemy is another great philosopher who taught the geocentric theory theory persuasively the geocentric theory is also known as the Ptolemaic theory
What are 3 main reasons that the church in the Middle Ages adopted the geocentric theory as religious truth
The concept of the prime mover who is God,the fact that hell is in the center of the earth and heaven is outside of it, and Thomas aquinas who took Aristotles arguments into church theology in 1100s ad which set egocentrism into church as the “truth”
What type of motion is the planets orbital movement
Violent motion
What are the 2 types of motion?
Violent motion and natural motion
What is the cause of natural motion
When an element mad up of earth air fire or water returns to it home
What is the cause of violent motion
The prime mkver
What did Aristotle think about the celestial bodies
He thought that all celestial bodies would eventually stop just like how all objects in motion will eventually stop so therefore there needed to be a supreme being
What does this supreme being do
This supreme being keeps the stars and planets in motion by pushed them
What was earth air Fire and Water considered
Corruptible and vile
Whhy were the stars and planets considered perfect
Because they were mad if a perfect element called quintessence
Where does the prime mover live
In the celestial sphere
What and when did Hipparchus discover
Trigonometry 160 bc
Was he a geocentric or heliocentrist
Geocentrist