Transcript Slide 1

The Copernican Revolution – A New Earth?
Unit 3 - Day 3
A Paradigm Shift?
In his book, The Copernican Revolution, noted historian of science Thomas Kuhn argues that
Copernicus’s work on astronomy brought about a paradigm shift in the way people saw
the world.
Question: What is a paradigm?
Paradigm – a way of viewing or understanding reality
Question: How can one’s paradigm shift?
Paradigm Shift – Kuhn argued that a paradigm shift
occurs when a person or community is presented with
evidence that cannot be explained by the currently
accepted way of viewing or understanding reality.
Paradigm Shift – A Simulation
Paradigm Shift – A Simulation 2
Note: Neither of these images “are” paradigm shifts. They simulate the experience
by showing how we can interpret the same information in two different ways, and
move back and forth between the two interpretations.
Nicholas Copernicus
Nicholas Copernicus (1473-1543)
 Born in Polish city of Torun
 Father dies when he is young, raised by uncle an
influential bishop
 Studies at the University of Krakow
 Goes to Italy to earn doctorate in Law and study
medicine
 Upon return, becomes a canon (cleric) and serves
as an administrator for bishop
 Dabbles in mathematics and astronomy as a
hobby.
 Makes astronomical tables based on his
observations.
 1510-1514 becomes involved in Church
calendar reform – formulates heliocentric theory
Heliocentric Theory
Calendar Reform
Problems with existing mathematical models for calculating calendar:
1. Models are mostly accurate but require periodic “reboots” every few hundred
years.
2. Mars does funky things. Aristotelian model needs complicated solutions.
Retrograde motion of Mars – time-lapse photo
The Mars Problem
How Aristotelian astronomers explain
retrograde motion with epicycles.
For Copernicus the solution to
retrograde motion is simple – the Earth
(which moves) simply passes Mars
Copernicus Discussion Questions
•What does Copernicus think is wrong with the way that mathematicians have gone
about solving the problems with the existing calendar?
• Why does he decide to approach the problem differently?
•Why does he believe his model provides a better solution to the problem?
•What concerns does he have about the way his theory will be received?
• What does he feel is the proper relationship between reason and authority?
On the Revolutions (1543)
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1514 Copernicus distributes a pamphlet
called the Commentaries which sketches
out his conclusions to his friends and other
mathematicians
1543 – finally publishes On the
Revolutions on the Heavenly Spheres;
containing hundreds of pages of dense
calculations – which only mathematicians
can read
Caused very little immediate controversy
– in part because it was widely seen as
just a tool for calculation not a real
system.