EconCSLib: A Lean Library for Computational Economics and AI-Assisted Research

2026-06-14

AI Summary

This work addresses the longstanding absence of reusable, machine-verifiable formal libraries in computational economics—encompassing game theory, mechanism design, and social choice—by presenting the first systematic effort to develop an open-source formalization in the Lean 4 theorem prover. The library captures core definitions and theorems from these fields and integrates AI-assisted tools to facilitate large-scale mathematical formalization. Beyond providing machine-checkable representations of classical economic theories, the project demonstrates the feasibility and promise of AI-supported formal methods in economic research. This contribution establishes a novel paradigm for future endeavors in formal modeling and automated reasoning within economics, enhancing rigor, reproducibility, and scalability in theoretical exploration.

Abstract

Mathematical formalization uses interactive theorem provers to turn informal mathematical statements into machine-checkable artifacts. The success of mathlib, a large collaborative library for Lean, illustrates the potential of this approach. Recent progress in AI-assisted programming and theorem proving is also making large-scale formalization more practical. This paper presents EconCSLib, an early Lean 4 library for computational economics, as both infrastructure and a case study for AI-assisted formalization. The library aims to provide reusable definitions and theorems for game theory, mechanism design, social choice, and related areas. Beyond verified proofs of existing results, the library also aims to host machine-checked open problems and formalization of modern research papers. We discuss the design principles behind the library, the lessons learned from its development, and future directions for AI-assisted formalization in computational economics.

Problem

• computational economics
• formalization
• interactive theorem proving
• machine-checkable proofs
• AI-assisted research

Innovation

• formalization
• interactive theorem proving
• AI-assisted programming
• computational economics
• Lean 4