Atlas record: https://www.aitimeline.dev/en/events/evt-0090/

Research · April 1960

Placed by the contemporary primary publication. The exact event date is not known; its documented interval appears below.

Lisp

McCarthy described a language in which program and data share one list form, and computation is defined by recursive functions over symbols.

Why it matters

Symbolic computation got a working tool, and nearly every AI system of the next thirty years was written in it.

The paper introduced eval as a mathematical definition of the language; Steve Russell noticed eval could be implemented and did so on the IBM 704. Garbage collection, closures and the sameness of code and data entered common use from here. STUDENT, DENDRAL and SHRDLU were all written in Lisp.

Event record

Event date

1958 – April 1960

Timeline date

Primary publication date

Verification

Sources gathered automatically · September 17, 2026

Lines

ID

evt-0090

Work on the language began in 1958; the paper appeared in CACM in April 1960. The anchor is the publication.

Sources

primary Recursive Functions of Symbolic Expressions and Their Computation by Machine, Part I
Communications of the ACM · Published April 1960
archive Recursive Functions of Symbolic Expressions and Their Computation by Machine (AI Memo 8)
MIT DSpace (MIT AI Lab memo AIM-008) · Published March 13, 1959

Related events

Earlier

Related Programs with Common Sense 1958
The language gave a way to write the symbolic expressions an advice taker needs.

Later

Builds on SAINT 1961links to this record
The program was written in Lisp.
- A Heuristic Program that Solves Symbolic Integration Problems in Freshman Calculus · MIT
Builds on STUDENT 1964links to this record
The program was written in Lisp.
- Natural Language Input for a Computer Problem Solving System · MIT
Builds on SHRDLU 1971links to this record
The program is written in Lisp, with Micro-Planner built on top of it.
- Procedures as a Representation for Data in a Computer Program for Understanding Natural Language · MIT
Builds on LCF: a program that checks proofs about computation 1972links to this record
According to Gordon's retrospective, Edinburgh LCF, including the ML interpreter, was implemented in Lisp.
- From LCF to HOL: a short history (Mike Gordon) · University of Cambridge Computer Laboratory (author's copy)
Builds on Boyer and Moore: induction without human hints 1973links to this record
The program proves theorems about recursive LISP functions and runs them in a LISP interpreter to build its induction formula.
- Proving Theorems about LISP Functions (Robert S. Boyer, J Strother Moore), Advance Papers of the Third International Joint Conference on Artificial Intelligence, 486-493 · IJCAI
Builds on MYCIN 1974links to this record
The system is written in Lisp.
- Computer-Based Medical Consultations: MYCIN · American Elsevier
Related The Connection Machine 1985links to this record
The machine was built for parallel data processing rather than sequential execution of symbolic code.