@Steve Leo well, I used one kind of abstract algebra (group theory, which is the abstraction of symmetry) to understand DEB. But, I feel like I need category theory to understand Godley tables. Category theory is the abstraction of composition. You see, when we abstract from the transaction level (DEB) up to the sector level (macroeconomics a la Godley), there are some flows that are not reversible (e.g., imports and exports). The fact that there are no inverses (e.g., exports and imports are irreversible) means that I can’t ”group” them with group theory. This means I need a different and more abstract kind of algebra to compose the macroeconomic circuit, hence my interest in category theory. I’m studying physics and circuit math in the fall. I figured out the DEB math for the first law of thermodynamics, and now I’m focused on the second law. I think the math is deceptively simple. It’s as perfect as Euclid’s ratios.