… is from page 250 of Axel Leijonhufvud’s 1981 collection, Information and Coordination: Essays in Macroeconomic Theory; specifically, it’s from his superb chapter “Costs and Consequences of Inflation” (original emphasis):
In a regime of unstable money, it is not rational for people to rely on private contracts and agreements to the same extent as in a stable money regime. The substitute instrumentality is political. We expect people to use their votes and lobbies increasingly to help ensure for themselves a predictable real income. Such activity may take the form of demands on the government itself for adjustment of taxes, for transfer payments, for “free” or subsidized government-provided services.