Receipts: Economics Class, Lesson One — “Priced In” at What? (September 17, 2026)
The paperwork behind Lesson One on TikTok. That video used no numbers from this week’s market on purpose. What it did use is history, and history has receipts. Every name, date, and quote I said is below, with where to read it yourself.
What I said on camera
- “Priced in” is not a finance term. It is a password. The test is two numbers: what was expected, and what came in.
- A price is not a fact. A price is a bet: the average of everybody’s guess about the future, with money behind it.
- Price moves on the gap between what happened and what was expected, not on what happened.
- The idea is 126 years old and used to be called “discounted.” The phrase “priced in” only became common in the 1990s.
- The guess is published: the consensus next to every scheduled number, a market that trades the expected interest rate, and the options market that prices the size of the expected move.
- The same gap is a stampede against a crowded room and a yawn with it. Who is standing where is published every week.
- Nothing is ever fully priced, because the next guess starts the second the number lands.
The history, verified
| What I said | The record | Where to read it |
|---|---|---|
| Louis Bachelier, 1900 | Doctoral thesis Théorie de la spéculation, defended at the Sorbonne March 29, 1900. Original French: “L’espérance mathématique du spéculateur est nulle.” Standard translation: “the mathematical expectation of the speculator is zero.” | Annales scientifiques de l’École Normale Supérieure, 1900; English translation in Cootner, ed., The Random Character of Stock Market Prices, 1964 |
| William Hamilton, 1922 | “News known is news discounted. What everybody knows has ceased to be a market factor, except in the rare instance of a panic.” Hamilton was the Wall Street Journal editor who carried on Charles Dow’s work after Dow’s death. | The Stock Market Barometer, 1922, chapter VII |
| What Charles Dow himself wrote | Wall Street Journal editorial, July 20, 1901: the market “represents a serious, well-considered effort on the part of farsighted and well-informed men to adjust prices to such values as exist or which are expected to exist in the not too remote future.” The slogan “the averages discount everything” came later, from Robert Rhea’s The Dow Theory (1932). I credited Hamilton on camera for that reason. | Quoted in Hamilton, 1922, chapter VII |
| “Buy the rumor, sell the news” | A Wall Street saying with no known author. The New York Times called it an “old apothegm” on December 13, 1956. | New York Times, “Stocks Retreat Third Day in Row,” December 13, 1956, p. 59 |
| Paul Samuelson, 1965 | “Proof That Properly Anticipated Prices Fluctuate Randomly,” Industrial Management Review 6(2), Spring 1965, pp. 41–49. | MIT Sloan; widely reprinted |
| “The phrase got popular in the nineties” | Google Books Ngram for “priced in”: negligible before the 1980s, sustained rise through the 1990s, peak around 2004. | Google Books Ngram Viewer, English 2019 corpus |
| “126 years” | 2026 minus 1900. | Arithmetic |
Where the guess lives
| What I said | The record | Where to read it |
|---|---|---|
| “News wires poll economists every week” | Bloomberg surveys about 1,600 forecasters, typically around 80 per major release, with history back to 1997. Reuters polls cover 900-plus indicators with history from 1999. The Dow Jones/Wall Street Journal survey has run for decades. | Bloomberg economist-estimates fact sheet; LSEG Reuters Polls page; Wall Street Journal Economic Survey |
| “A market where people bet on what the rate will be” | Fed funds futures began trading at the Chicago Board of Trade in October 1988. | Federal Reserve Bank of Richmond, Economic Quarterly, Spring 2001 |
| “The options market tells you how big a move the crowd expects” | The implied move is the size of the up-or-down swing the options market is pricing for an event, read from the price of the at-the-money call plus put. It is a size, not a direction. | Cboe education materials |
| “Who is standing where is published every week” | The CFTC Commitments of Traders report, Fridays at 3:30 PM ET, positions as of the prior Tuesday. | CFTC |
Two things I left in the drawer
Eugene Fama’s 1970 paper in the Journal of Finance defined an “efficient” market as one “in which prices always ‘fully reflect’ available information.” And Keynes, in chapter 12 of The General Theory (1936), described the newspaper beauty contest where “we devote our intelligences to anticipating what average opinion expects the average opinion to be.” Both say the same thing the umbrella says. I kept the umbrella.
The daily version of this
I’m Nathan Banks. I’ve been trading since 2001 and teaching the institutional framework, the Institutional Expansion Cycle™, since 2012. The class is free. The morning version of the reading, dated the same way, is the Daily Market Research. The free trade desk is at tradewithbanks.com/join. Nothing here is financial advice; trading involves risk.
