Easy money fuels speculative bubbles

Abundant money and cheap credit are the fuel of speculative bubbles: when yields on safe assets fall, savers search for yield and "would often rather invest in something ridiculous than accept a low interest rate on a safe asset." This is a staple of bitcoin market debates — both as an explanation of bitcoin's price cycles tracking global liquidity conditions, and as a bitcoin-side critique of credit-driven monetary regimes.

Nuance: The historical record in Quinn and Turner supports the mechanism but complicates simple central-bank blame. Supporting: the Australian land boom followed rate cuts that pushed savers toward risk; Japan's 1980s bubble followed deliberate policy — M3 grew 141 per cent over 1980–1990, treasury yields hit post-war lows (2.4 per cent in 1987), and household debt rose from 52 to 70 per cent of GDP as policy eroded norms against borrowing. Complicating: for the 1920s US boom the authors argue the "Fed was too loose" story does not fit the evidence — meeting minutes show the Federal Reserve was, if anything, excessively concerned with curtailing margin lending; the credit fuel came substantially through broker loans whose volume tracked the DJIA, and gaps left by pressured banks were plugged by other lenders. Credit conditions are one side of the triangle, not the whole cause, and the credit can originate outside the central bank's direct control.

Common misstatements: "Central banks cause every bubble" (the 1920s case shows private credit channels can supply the fuel even against central-bank pressure). "Bitcoin only rises because of money printing" (liquidity conditions are an enabling condition in this framework, not a complete account of any asset's price — the framework also requires a marketable asset, active speculation, and a spark).