I wonder if the same force that pulled the apple to the ground was tugging on the moon.
It was just strong enough to bend the moon's motion into a circular path around earth.
This is my my great insight. A single force explained a falling apple and the movements of heavenly bodies as well. I will call this force gravity.
I stated the law of gravity in a simple formula. All physical objects had a force of attraction between them.The strength of force depended on the masses of the objects and the distance between them.
The result of the example earth and the moon tugged on each other at a certain points space these tugs cancelled other out. The result was that the moon was trapped in its orbit around Earth. I also published a book called Principia the book represented the law of gravity.