From the Path: Thirteen Ahead, Eleven Behind

UENO — Two kinds of time trouble follow me around, and only one of them is worth a paragraph. The first is jet lag, which is real, tedious, and has nothing to teach anybody: my body is keeping East Coast hours in a city that gave them up long ago, and it will right itself … Read more

Why the Periphery Is the Principal (or, “Take Your Hand Off the Lever”)

A confession before we start: I billed this as three posts, and the arithmetic has not cooperated (Ed.: You definitely know non-cooperation, John). The last two turned up a result and a question big enough that I’d rather run long than rush them, so the series will continue past today. This post is the third, … Read more

What a Graph Does to an Adverb (or, “Bring a Pencil”)

On Monday I split the payoff an agent earns into a part that travels with the strategy and a part that stays with the seat, \(f_i = \alpha_{s_i} + \beta_i + \varepsilon_i\), and promised that the positional term \(\beta\) has a closed form that takes about three lines to derive. Today we derive it. The … Read more

Who Do You Look To? (or, “Not Everybody Can Be Taylor Swift”)

When you face a decision you don’t know how to make, you look sideways. You find someone who is doing well — the colleague who made tenure, the neighbor whose kids turned out kind, the friend who somehow retired comfortably a decade early — and you copy what they did. But the rule has a … Read more

No News Is Bad News (or, “The Junk Drawer Is a Bet”)

“Should I put this in the junk drawer?” “I dunno. Do you think you could figure out where it goes?” That exchange is short enough to miss, and it is the entire subject of today’s post. The first post in this series introduced the junk drawer as a load-bearing component of any well-designed classification system, … Read more

Because I Said So (or, Why a Smart President Should Want to Lose Trump v. Cook)

The Supreme Court has twenty-three cases left to decide this month, and one of them is Trump v. Cook. The facts, briefly: last August, the President posted a letter announcing the immediate removal of Federal Reserve Governor Lisa Cook, citing uninvestigated allegations that she misstated her residency on mortgage paperwork before she joined the Board. … Read more

Four Numbers Aren’t a Dilemma

A new paper by Alexandre Morozov and Alexander Feigel in PNAS offers a genuinely interesting evolutionary result. If each player in a population of Prisoner’s Dilemma agents carries an opponent-indexed cooperation probability — \(p_{c,i\to j}\), one entry per partner identity — then selection and mutation routinely produce cooperative configurations. The press release framed this as … Read more

From the Path: When Better Looks Worse

John and Maggie being reflected in Nancy

NANCY — A few days ago I promised a dispatch on the keynote, and here it is. The eighth International Conference in Philosophy and Economics met this week in Nancy, and the keynote was given by my closest collaborator, who is also my wife, Maggie Penn. Her title was “Three Paradoxes of Optimal Evaluation.” I … Read more

From the Path: The Two Body Illusion

NANCY — I have come up out of the tunnel, across France, and into Lorraine, to a conference on economics and philosophy, and the first thing worth saying about the host city is that it is the birthplace of the man who discovered that three of anything is trouble. Henri Poincaré was born here in … Read more

From the Path: The Map Was the Easy Part

BENEATH THE ENGLISH CHANNEL — Having just reoriented myself to turning my head to the right when about to cross the street, I have boarded the train at St. Pancras with Maggie, as we leave London and head to the 8th Conference on Philosophy and Economics in Nancy, France — via Paris, of course. There … Read more