Alonzo Church (June 14, 1903
– August 11, 1995) was an American mathematician and logician who made major contributions to
mathematical logic and the foundations of theoretical computer science.
He is best known
for the lambda calculus
, Church–Turing thesis
, Frege–Church ontology
, and the
Church was born on June 14, 1903 in Washington, D.C. where his father, Samuel Robbins Church, was the
Justice of the Municipal Court for the District of Columbia.
The family later moved to Virginia after his father lost this
position because of failing eyesight. With help from his
uncle, also named Alonzo Church, he was able to attend the
Ridgefield School for Boys in Ridgefield, Connecticut. After graduating from Ridgefield in 1920,
Church attended Princeton University where he was an exceptional student, publishing his
first paper, on Lorentz
transformation, and graduating in 1924 with a degree in
He stayed on at Princeton, earning a Ph.D.
in mathematics in three years
under Oswald Veblen
He married Mary Julia Kuczinski in 1925 and the couple had three
children, Alonzo Church, Jr. (1929), Mary Ann (1933) and Mildred
receiving his Ph.D. he taught briefly as an instructor at the
Chicago and then received a two-year National Research
Fellowship. This allowed him to attend Harvard
University in 1927–1928 and then both University of
Göttingen and University of Amsterdam the following year. He taught at
Princeton, 1929–1967, and at the University of
California, Los Angeles, 1967–1990.
In 1990, he received the Doctor
Honoris Causa from the State University of New
York at Buffalo
in connection with an international symposium
in his honor organized by John
. He had previously received honorary
doctorates from Case Western Reserve
University (1969) and Princeton University (1985).
He died in
1995 and was buried in Princeton Cemetery.
Church is best known for the following accomplishments:
The lambda calculus emerged in his famous 1936 paper showing the
existence of an "undecidable
". This result preceded Alan
's famous work on the halting
, which also demonstrated the existence of a problem
unsolvable by mechanical means. Church and Turing then showed that
the lambda calculus and the Turing
used in Turing's halting problem were equivalent in
capabilities, and subsequently demonstrated a variety of
alternative "mechanical processes for computation." This resulted
in the Church–Turing thesis.
The lambda calculus influenced the design of the LISP programming language
languages in general. The Church
is named in his honor.
Church's doctoral students were an extraordinarily accomplished
lot, including C. Anthony Anderson
, Peter B. Andrews
, George A. Barnard
, William W. Boone
, Alfred L. Foster
, Leon Henkin
John G. Kemeny
, Stephen C. Kleene
, Maurice L'Abbé
, Gary Mar, Michael O.
, Nicholas Rescher
, Hartley Rogers, Jr.
, J. Barkley
, Dana Scott
, Raymond Smullyan
, and Alan Turing
. See 
.A more complete list is at 
as part of the Mathematics Genealogy
- Alonzo Church, Introduction to Mathematical Logic
- Alonzo Church, The Calculi of Lambda-Conversion (ISBN
- Alonzo Church, A Bibliography of Symbolic Logic,
1666–1935 (ISBN 978-0821800843)
- C. Anthony Anderson and Michael Zelëny, editors, Logic,
Meaning and Computation: Essays in Memory of Alonzo Church
- Enderton, Herbert B., Alonzo
Church: Life and Work. Introduction to the Collected Works
of Alonzo Church, MIT Press, not yet published.
- Enderton, Herbert B., In memoriam: Alonzo Church, The Bulletin of
Symbolic Logic, vol. 1, no. 4 (Dec. 1995), pp. 486–488.
- Wade, Nicholas, Alonzo Church, 92, Theorist of the Limits of
Mathematics (obituary), The New York Times, September
5, 1995, p. B6.
- Hodges, Wilfred, Obituary: Alonzo Church, The Independent
(London), September 14, 1995.
- Alonzo Church interviewed by William Aspray on
17 May 1984. The Princeton Mathematics Community in the 1930s:
An Oral-History Project, transcript number 5.
- Rota, Gian-Carlo, Fine Hall in its golden age: Remembrances of Princeton in
the early fifties. In A Century of Mathematics in America,
Part II, edited by Peter Duren, AMS History of Mathematics,
vol 2, American Mathematical Society, 1989, pp. 223–226. Also