Stephen Cole Kleene
Stephen Cole Kleene
Stephen Cole Kleene /ˈkliːniː/ KLEE-neewas an American mathematician. One of the students of Alonzo Church, Kleene, along with Alan Turing, Emil Post, and others, is best known as a founder of the branch of mathematical logic known as recursion theory, which subsequently helped to provide the foundations of theoretical computer science. Kleene's work grounds the study of which functions are computable. A number of mathematical concepts are named after him: Kleene hierarchy, Kleene algebra, the Kleene star, Kleene's recursion theorem...
NationalityAmerican
ProfessionMathematician
Date of Birth5 January 1909
CountryUnited States of America
For example, the philosophers who were interested in logic were probably rather logical for mathematicians. But the ASL got us together, so we could talk to each other and publish in the same journal.
I suppose Church's course had six or eight people in it, but I can't remember the name of even another one of them now. None of them went into logic.
I returned to Princeton with a research assistantship on February 7, 1934, and remained there through the academic year 1934-35.
Those three years ended with June 1933. At that time I left Princeton, having submitted my Ph.D. thesis.
As I say, there was this movement to try to bring philosophers and mathematicians together into an organization where they would talk to each other. An organization wasn't effective unless you had a journal. That's about all I know.
And what I learned in Church's course. He trained us intensively in his new system, which he was just developing. Two papers were presented. I think the second paper wasn't published until well after the course was finished.
I had a liberal arts education at Amherst College where I had two majors, mathematics and philosophy.
When I got to Princeton I made a point of attending the Philosophy Club and listening to the lectures, but I didn't get involved in any discussions in those clubs. I guess after the first year, I dropped that.
I'm sure Church got some of his ideas from this trip to Europe.
I went to Princeton from Amherst, where I split my interests between mathematics and philosophy.
Here at Wisconsin we didn't get an undergraduate course in mathematical logic until the '60s.
It wasn't until my second year that I got to actually work with Church.
I had some hesitations about philosophy because, if you worked out a philosophical theory, it was hard to know whether you were going to be able to prove it or whether other theories had just as good a claim on belief.
I think that after Church got his Ph.D. he studied in Europe, maybe in the Netherlands, for a year or two.