When you observe a falling rock (or anything else) it imparts to you a particular instance of sense-knowledge. Theories are abstractions and as such must be grasped by the intellect and not the senses. You can't observe an abstraction. So, you can't demonstrate "the theory of gravity" by dropping a rock, no moreso can you demonstrate some "theory of color" by noticing that a particular apple is red. Abstractions apprehended by the intellect must be verified or refuted by acts of the intellect: reason, judgement, etc.
that is evidence that supports the TOG. but it is not "proof.'
Obviously it isn't proof, neither is noticing that an apple is red any sort of proof of a "theory of color", because all it is is an observation and not a body of reasoning. As if observation is all there is, and reasoning does not exist, you conclude from this that it isn't possible to verify theories of color or gravity. But this conclusion does not follow. What is wrong with saying that Newton's theory of gravity can be verified by computing the orbit of Ceres and comparing with observation? This is a completely comprehensible and sensible statement. I see no reason to avoid it and instead employ absurd Popperisms (however much in vogue they may be) like 'Newton's theory of gravity can't be verified but if the computed orbit of Ceres does not match observation then it is falsified."
I can prove the existence of the rock, I can't 'prove' the nonexistence (negative) of the rock, you might be hiding it in your fridge.
Why not? All you have to do is open the door, look inside, and note that there is no rock.
when scientists build a theory they don't try to prove a theory, they look for exceptions to the theory. Any exceptions disprove the theory.
As you know, astronomers discovered that the orbit of Uranus deviated from expectation. Physicists did not throw Newton's theory in the garbage. Rather they looked for an unknown object that was the cause.
That is what Aristotle thought. That everything could be determined by reason alone. What we have learned is that abstract reasoning has to be verified by observation, not more 'reasoning.'
What is wrong with saying that Newton's theory of gravity can be verified by computing the orbit of Ceres and comparing with observation?
Absolutely nothing is wrong with saying that it is verified. I verify the TOG every time I go flying. It isn't proof though. Proof is a higher standard than we are able to achieve.
I can prove the existence of the rock, I can't 'prove' the nonexistence (negative) of the rock, you might be hiding it in your fridge.
Why not? All you have to do is open the door, look inside, and note that there is no rock.
Because the rock could be anywhere and I would have to exhaustively search everywhere. That can't be done.
As you know, astronomers discovered that the orbit of Uranus deviated from expectation. Physicists did not throw Newton's theory in the garbage. Rather they looked for an unknown object that was the cause.
Yes, but they were unable to account for Mercuries deviation and Einsteins theory could. I will also agree with you that Einsteins (you didn't state this but I can guess) theory did not disprove Newtons theory, but rather built on it.