Mapping the Narrow Corridor with LLMs

A project by Ebrahim M. Songhori.

Overview

In The Narrow Corridor: States, Societies, and the Fate of Liberty, Daron Acemoglu and James A. Robinson — awarded the 2024 Nobel Prize in Economics for the body of institutional research this book belongs to — trace national histories as paths through a two-dimensional (state power, society power) space, with a narrow corridor between the two axes where liberty is sustained. The book, however, plots none of these paths: quantifying the two axes at each historical moment is the labor-intensive, judgment-laden task that has kept the framework qualitative.

The Narrow Corridor and its four Leviathan regions: Despotic, Shackled, Absent, and Paper
The Narrow Corridor and its four Leviathan regions.

This project asks whether a large language model (LLM) can operationalize it. It scores a country period by period — using chain-of-thought prompting (events first, then a score) and in-context anchoring on prior periods against an explicit 0–10 rubric, returning schema-validated scores — to produce reproducible trajectories that can be checked against an established expert index (V-Dem).

The Atlas

The accompanying short paper builds a twelve-country trajectory atlas — Iran, France, the United Kingdom, the United States, China, Chile, Colombia, the Democratic Republic of the Congo, Lebanon, Zambia, Somalia, and India — chosen so that at least two countries fall in each of the book's four Leviathan types: Despotic, Shackled, Paper, and Absent. It compares four LLMs (Gemini, Claude, GPT, and an open-weight Qwen), checks the scores against the V-Dem expert index, and quantifies inter-model agreement. Because every country is scored against the same fixed rubric, all twelve sit on one shared map of the book's regions.

Where each of the twelve countries sits in 2020 over the book's Leviathan regions
Where each of the twelve countries sits in 2020, on one shared map.

How It Works

The tool is a provider-agnostic Python package (via LiteLLM) that scores any country over any period range, caches responses so re-runs are free, and can plot a trajectory or animate it to reveal each period's key event. A build step turns a directory of runs into a self-contained, hostable gallery of plots with click-to-play animations. Every run in the paper — 12 countries × 4 models, plus the V-Dem and ensemble atlases — ships with its full prompt and response transcript for reproducibility.

Animated trajectory of the United States through the Narrow Corridor, 1789 to 2020
The United States, 1789–2020, decade by decade (ensemble mean).

Links