Unit 4 - "On the Movement of the Earth"

Author Bio: Nicolas Copernicus (1473-1543) was a Renaissance mathematician and astronomer, who created a model that made the Sun the center of the universe instead of the Earth. He had a famous book called On the Revolution of the Celestial Spheres and it was published right before his death in 1543. This book triggered the Copernican Revolution. Copernicus also made other discoveries that contributed to the Scientific Revolution.

Date/Context: Copernicus wrote "On the Movement of the Earth" in 1543, right before his death, and also during the Renaissance era. During the Renaissance era, it was time of questioning of everything, and in this text Copernicus was then questioning the then current views of the universe. The Renaissance era was time of new and flourishing ideas being distributed to the public. Copernicus wrote this in order to give the public a new idea about the universe and question what earlier scientists put forth about the universe.

Summary: Copernicus fears that his views in this book might see the disapproval of the public because the public was already used to the ideas they have bee taught. He wanted to think of a method of how these "spheres" moved by mathematics because he saw the inconsistency of the views of the previous mathematicians. Mathematicians were then unsure about the movement of the sun and the moon that they had no real constant of motion and revolution by the two and the other planets. Copernicus then read through the ideas of the other philosophers about the universe and realized that the earth does in fact move. He then realized that the other planets have to move with relation to the earth or it would produce mass chaos.

Key Quotations:

• "For the first time mathematicians are so unsure of the movements of the Sun and Moon that they cannot even explain or observe the constant length of the seasonal year."
• "I pondered long upon this uncertainty of mathematical tradition in establishing the motions of the system of the spheres."