u/Akshat_ki_mausi

How did Newton integrated Normal force in his work? It is not intuitive at all. We have a explanation of Normal force due to Electromagnetism and atomic view of matter. But how did Newton thought of Normal force or other macroscopic electrostatic forces? How did he get the intuition that even a static system(Earth and a ball) have constant forces canceling each other out.

Let's take inverse square proportionality, how come both both electrostatic and gravitational force are proportional to the inverse of area of a square which has a side length equal to the separation between points? Square is a man made construct, why does universe nicely adhere to inverse square law? I don't believe I communicated well enough, I might add more in comments.