Explain gravity if the earth isn’t flat.

Pro tip: you can’t.

The so-called “law of gravity” is flawed. It’s merely the best model available for the phenomena known as attraction and repulsion, which Newton clearly regretted mis-labeling as “gravity” later in life — going so far as to wonder if he had been better off keeping his knowledge to himself based on the myriads of foolishness that others spawned from his works.

If you haven’t done so before, reading Newton’s papers, especially on Optics, are very worthwhile. The modern theory of gravity is a bastardized and incomplete model based on the Law Newton was examining.

TL;DR: Better to be the “idiot” who questions and is wrong than the sheep who believes without understanding. The latter will never gain understanding, but the former are destined to learn the truth and understand it.