But it was obvious that they do.
Uhm, no. And Newton's law never said anything remotely like that.

Um, yes. Lots of things that are obvious, are not true. The "fact"
that heavier objects fall faster was obvious. It is also wrong.

Newton's law of universal gravitation led to the result that masses fall
to earth at the same rate. Newton had some other discoveries too.

Jose
--
"Never trust anything that can think for itself, if you can't see where
it keeps its brain." (chapter 10 of book 3 - Harry Potter).
for Email, make the obvious change in the address.