The Bathtub and the Tap: Forrester’s 1961 Stocks and Flows, the Inventory Cisco Could Not Drain, and Why the Long-Term Equity Investor Must Read Every Balance-Sheet Line as a History of Flows

Schematic of a tank with an inflow tap and an outflow drain, showing that a stock changes only through its flows

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Manish Goel, FCA

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The Bathtub and the Tap: Forrester’s 1961 Stocks and Flows, the Inventory Cisco Could Not Drain, and Why the Long-Term Equity Investor Must Read Every Balance-Sheet Line as a History of Flows

More posts

The Half-Life of Facts: Burton and Kebler’s 1960 Borrowed Metaphor, Poynard’s Forty-Five-Year Measurement of Clinical Truth, and Why the Long-Term Equity Investor Dates Every Input to a Thesis

Hanlon’s Razor: Bloch’s 1980 Printing of an Older Warning, the Arithmetic of Intent and Error, and Why the Long-Term Equity Investor Writes the Tripwire Before the Surprise

Occam’s Razor: Ockham’s Fourteenth-Century Rule of Parsimony, the Bayesian and Predictive Case for It, and Why the Long-Term Equity Investor Counts the Assumptions in a Thesis

The Stockdale Paradox: Collins’s 2001 Name for Faith in the End and Honesty About the Present, and Why the Long-Term Equity Investor Needs Both Without a Date Attached