Lisp and Lambda Calculus: A Tale of Theory and Practice

This article explores the relationship between Lisp and lambda calculus. John McCarthy, Lisp's creator, didn't fully grasp lambda calculus initially, yet borrowed its notation to create Lisp. Lisp isn't a direct implementation of lambda calculus but rather inspired by it, incorporating features of the IBM 704 hardware. The article delves into Lisp's early history, including the implementation of its evaluator EVAL and the connection between car/cdr operations and the IBM 704. Lambda calculus fundamentals are introduced, illustrated with a toy language called ΛΙΣΠ. Ultimately, the article reveals a fascinating, complex interplay between Lisp and lambda calculus, leaving much to explore in future installments.