Agreed, it’s astonishing intuition. It’s hard to call it a lucky guess when it is the last paragraph of Newton’s magnum opus. But very hard to explain.

Choosing my words carefully, I think it was a kind of deep and deliberate magic. Of the sort Newton ascribed to Pythagoras as the esoteric discoverer of the inverse square law of gravitation. (see “Newton and the pipes of pan”). Hooke also had a sort of musical, oscillatory, spiraling conception of mental phenomena. So it was in the Zeitgeist.

In any case, it is striking and amazing— and resonant in this age of vibes.