Thanks for the wall of text. :D Really appreciate it that you took the time to explain these things.

Anyway, I have some follow-up questions about the stability/volatility of theories. Recently, I've been thinking about the how firm and solid the models and theories are in different sciences. For example, physics has all the basics pretty well nailed down, whereas in psychology even the basic things tend to get frequent updates as more data becomes available and old ideas get challenged.

In physics, there are models that have known blind spots. Currently, we know that our model of gravity is ok for large objects such as tennis balls, planets, stars and galaxies. In an atomic scale though, our model of gravity just doesn't line up with our understanding of quantum mechanics. So what about Economics then? Have we identified serious flaws in our economic models, like we have with gravity, or are the models about as solid as the theory of atoms or energy?

Or maybe the models are more like suggestions that kinda work occasionally, but mostly you have to take the predictions with a grain of salt. You mentioned that the idea of controlled inflation smoothing out larger recessions and depressions is still debated, so maybe that concept could be contrasted with the theory of gravity. It works for the most part, but there are known issues with it.

When atoms and electrons were discovered, a whole lot got rewritten, but now that we've been working with these fancy new particles for about a hundred years, this part is looking pretty well established. Finer details like string theory is anything but solid, but the big picture is nice and firm. It doesn't look likely that any new data would lead to us throwing away our idea of atoms. Quite the contrary, now that we've even got pictures of individual atoms, and we have the means to manipulate them individually. Obviously, the finer details are absolutely going to change as better data becomes available, but those topics are quite exotic, like dark matter and dark energy.

The whole concept of atoms is about as solid as it gets, but are there comparable theories in economics? Something fundamental that has been tested countless times and nobody has been able to prove that the idea is wrong. Something that is accepted as a foundational cornerstone and is unlikely to get thrown out the window. Maybe something like supply and demand, but is that actually solid enough? Does that stuff get tested, debated and challenged? Have economists found some holes in these kinds of theories?