[WalterBright]

Sure they watched the paths. That doesn't tell them what they were, how far away they were, helicentric vs geocentric, etc. Anybody can watch paths and notice they repeat.

> heliocentrism are ultimately just an optimization that wasn't obvious, necessary, or meaningful given what little practical use there was to the paths of those planets until very recently

True, but that wasn't my observation. My observation is it was not advanced, sophisticated, etc.

[felipeerias]

It was actually extremely complex and sophisticated. Getting accurate measurements was seriously tricky and making sense of them involved doing complex calculations (particularly spherical trigonometry) by hand. Some phenomena, like the precession of the equinoxes, required aggregating observations which had been taken over several centuries.

A good book to get a sense of this complexity is “The Light Ages” by Seb Falk.

[WalterBright]

Unfortunately, a calculation that matches a pattern does not confer any understanding of the nature of the solar system.