Chapter 3 — Debt and Exponential Reinforcement
Debt is a claim on future energy.
Not future money — future energy. A bond, a mortgage, a credit facility: each is a contract that says someone, somewhere, will do work tomorrow to honour a promise made today. Money abstracts this. Interest compounds it. But beneath the abstraction, every debt instrument is a claim on human labour, natural resources, or both.
Compound interest is exponential reinforcement. At 5% annual interest, a debt doubles in fourteen years. At 7%, ten years. The mathematics is simple. The implications are not.
Exponential growth functions inside finite systems create instability. This is not ideology — it is thermodynamics. A bacterium in a petri dish doubles every twenty minutes. For hours, the colony grows luxuriantly. Then, in a single generation, it hits the boundary of the dish and collapses. The bacterium did not make a mistake. It optimised perfectly within its local frame. It simply had no mechanism to detect the boundary.
Debt scaled extraordinarily well. The Medici built an empire on double-entry bookkeeping. The British Empire ran on sovereign debt. American postwar prosperity was turbocharged by consumer credit. Debt allowed optimisation to outrun physical constraint — to pull future resources into the present and deploy them at scale.
Too well.
The compounding curve does not care about fish stocks. It does not care about soil depletion rates. It does not care about the atmospheric concentration of carbon dioxide. It is an abstraction optimising itself, decoupled from the physical systems that must ultimately honour its claims.
Not evil. Not stupid. Structurally unstable.