I’m an applied mathematician turned macroeconomist: what you accuse in your first two paragraphs is true, but it is not for want of trying. We just lack the inv

I’m an applied mathematician turned macroeconomist: what you accuse in your first two paragraphs is true, but it is not for want of trying. We just lack the invariants and symmetries that physicists luxuriate in. We literally have nothing more to work with than what statistics can measure, typically as ambiguous time-series with dozens of aggregate variables subject to wide observation errors and biases. It’s pretty awkward, and we’re very much aware of it.