💬 [E6209] Historical analysis of Irving Fisher's famous declaration that stocks had reached a 'permanently high plateau' on October 15, 1929, just weeks before the crash. Fisher lost his entire $10+ million fortune, illustrating the danger of dismissing correction risk even when backed by sophisticated quantitative models and diversification principles.

🟢 [E6211] Traces the intellectual origins of modern portfolio construction to Harry Markowitz's portfolio theory, which demonstrated mathematical diversification benefits through correlation effects. WWII operations research veterans applied military risk-return optimization frameworks to investment problems. Edgar Lawrence Smith's study found stocks outperformed bonds over the 1871-1938 period, influencing long-term asset allocation thinking.

🟢 [E6210] Chronicles the foundational development of quantitative cycle frameworks from the early 1900s through WWII. Louis Bachelier's 1900 thesis described stock price movements as random walks following bell curve distributions. Alfred Cowles's 1932 study showed random card selections outperformed 24 professional forecasting services, and Holbrook Working in 1948 argued that 'apparent imperfection of professional forecasting may be evidence of perfection of the market.'