“The cycle of manias and panics results from the pro-cyclical changes in the supply of credit; the credit supply increases rapidly in good times, and then when economic growth slackens, the rate of growth of credit has often declined sharply. A mania involves increases in the prices of real estate or stocks or a currency or a commodity in the present and near-future that are not consistent with the prices of the same real estate or stocks in the distant future.” —Charles P. Kindleberger & Robert Z. Aliber