### Big picture
You can loosely view sustained inflation as a “tendency toward disorder” in the nominal side of the economy, unless active forces (policy/institutions) restrain it—similar to how entropy rises unless constrained. The analogy is suggestive but breaks in important ways.

### Mapping the analogy
- **Isolated system**: A closed monetary regime (e.g., a fiat currency area with fixed institutions and no external anchor). In practice, think “the whole currency zone,” or at the limit, the global monetary system.
- **Particles**: Nominal contracts and prices (individual wages, goods prices, rents), or the agents holding/setting them. A microstate is the vector of all nominal prices and money/credit balances.
- **Energy**: Aggregate nominal spending power (e.g., money supply × velocity, MV) injected via credit creation, fiscal deficits, or monetary expansion.
- **Temperature**: Demand pressure relative to real capacity (e.g., nominal income growth vs. potential output) and/or inflation expectations that “heat up” price adjustments.
- **Macrostate**: The general price level and its rate of change (inflation), summarizing many micro price/contract configurations.
- **Entropy (analogue)**: Price-level drift and increased dispersion/volatility of relative prices that erode the information content of money as a measuring rod; more micro configurations are consistent with a given loose nominal stance.
- **Constraints (analogue to walls/low-temperature baths)**: Credible monetary policy (targets/rules), fiscal discipline, indexation norms, contract design, and competitive pressures that tie down nominal drift and reduce “disorder.”

### Where the analogy breaks
- **No true isolation**: Economies are open (trade, capital flows, imported goods/energy), and policy choices are exogenous; physics’ isolation is well-defined.
- **No conservation law**: Energy is conserved; money/credit are created and destroyed endogenously and by policy. Seigniorage incentives are institutional, not physical.
- **No unavoidable arrow**: Entropy must rise in isolation; inflation need not. Disinflation/deflation occur, and low/stable inflation is a policy outcome, not a law.
- **Measurement vs. microstates**: Entropy has a precise microstate count; inflation is an index with methodology choices and sector weights. Relative price changes (true “disorder”) differ from the overall price level.
- **Equilibrium meaning**: Thermodynamic equilibrium is passive; economic equilibria reflect expectations, strategy, contracts, and learning—purposive behavior has no physical counterpart.
- **Heterogeneity**: Temperature equilibrates; inflation differs across sectors and regions. Sectoral shocks can produce opposite price moves simultaneously.
- **Welfare/normativity**: Entropy is descriptive; inflation has welfare and distributional consequences (debtors/creditors, fixed-income holders) and policy objectives.

### Takeaway
- **Usefulness**: The analogy helps intuition about diffuse forces (credit creation, expectations) pushing toward nominal “disorder,” and the role of policy as a constraint that maintains low “entropy.”
- **Limit**: Inflation is not a physical inevitability; it’s a contingent, institutional phenomenon with agency, measurement issues, and no conservation law—so treat the analogy as metaphor, not mechanism.