Bubbles, as described by Charles Kindleberger, a financial historian, usually involve an initial displacement, followed by rapid credit creation and then a phase of euphoria.

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I've been re-reading Charles Kindleberger's The World In Depression 1929-1939.

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Charles Kindleberger has shown in his historical studies of financial crises.

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Charles Kindleberger set out three preconditions for a mania where prices overshoot the bounds of rational valuation, in his classic, Manias, Panics, and Crashes: A History of Financial Crises.

FORBES: That's Gold, Jerry! Gold!