1. What was the common belief (theory) about motion before the 1600's?

People then didn't really think about gravity, they simply accept the fact that it exists, without realising. View this from another angle. When a teacher explains something in the classroom, most of the time we simply accept it, without asking why. That right there, is acceptance. We simply accept it. Everyone would know that if they let go of something, it would drop. However, only Isaac Newton stopped to question why. Hope this helps :)

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