Newton believed that the solar system was inherently unstable. He thought that God must occasionally tinker with it, to reset the initial conditions, in modern parlance.
Laplace’s elegant application and elaboration of Newton’s Laws in his Celestial Mechanics demonstrates that Newton’s laws could indeed result in a stable solar system. When Napoleon asked him about the place of God in his solar system, Laplace reputedly replied, “Sire, j’ai pu me passer de cette hypothèse” — “Sir, I have been able to dispense with that hypothesis.”
Oh, so Laplace explained *why* the law of gravitation is what it is? Now, *that* would be quite a feat.
Laplace sounds a lot like modern scientists who confuse discovery with invention. They think that because they discovered something about nature, they invented it.
Newton, on the other hand, was intelligent enough to realize that he didn’t invent the laws of physics. I’ll take Newton’s humility over Laplace’s arrogance any day.
By the way, I’m not a physicist, but I have read credible claims that Newton’s physics was actually more sophisticated than he is given credit for today. The conventional wisdom is that Newtonian physics was “superceded” by Einstein’s theories. But some physicists contend that Newton’s actual formulations (as opposed to modifications and interpretations by others) were consistent with relativity. I am not competent to debate the matter, but I do find it interesting.