Speculation excesses are referred too as mania and revulsion from these excesses take the form of crisis, crashes, or panic which are historically common. The excess speculation builds as investor seize new opportunities for profits and are overdone. Hyman Minsky describes these new opportunities as the result of displacement. Displacement are events leading up to a crisis, such as, outbreak or end of war, bumper harvest or crop failure, widespread adoption of an invention, or some political event. Displacement must be a significant size. Displacement brings opportunities for profit and increased demand causes price to rise. Banks artificially increase supply without proportional increases in demand by expanding the money supply that demand would have generated. The money supply expansion is notoriously unstable. Feedback fuels Euphoria for price increase; the Euphoria turns investment from really valuable products to delusional ones. Boom is characterized as rising interest rates, as Banks threaten discredit and hedge against the speculation by raising rates; trading velocity increases and the velocity of circulation and turnover ratios rise; and stock prices increases. Boom is fed by expansion caused by bank credit; credit increases the money supply and destabilizes the investment.

Once the excessive character of the upswing is realized, the financial system experiences a distress and then rushes to reverse expansion resembling panic: real or financial assets converting to money, premature repayment of debt, and prices crashes in commodities. Minsky explains that selling at the top falters because there is not enough money too sell out at the top. Revulsion of the commodity halts banks from lending on the commodity as collateral, this is called discredit. Discredit leads the panic as people crowd to get out the door. People may stop trying to get out the door, if price falls and the commodity looks like a bargain, trade is cut and price declines stop hemorrhaging, or a lender convinces the market money will become available.

The world markets operate as if men are rationale over the long run. Irrationality may exist as economic actors choose the wrong economic model, fail to account for a particular piece of information, or fail despite a rational expectation as lags between stimulus and reaction fail to meet expectation. Composite fallacy confuses the truth, as investors believe that the whole is more than the sum of its parts. Speculation leads to disaster and must be borne by the central bank.