"The persistent recurrence of speculative excess is a defining feature of financial capitalism wherever and whenever investors have the opportunity to trade assets. For the last 500 years, from tulip bulbs in the 1630s to cryptocurrencies today, the prices of assets have been subject to waves of herding behavior and momentum investing, with prices decoupling from any relationship to past, present and prospective cash flow. The economic historian Charles Kindleberger and the economist Robert Aliber summarized the phenomenon in their book on financial crises:"