Stephen Kleene

Updated: 09/15/2017 by Computer Hope

Stephen KleeneName: Stephen Kleene

Born: January 5, 1909 in Hartford, Connecticut USA

Death: January 25, 1994 (Age: 85)

Computer related contributions

  • American mathematician who co-founded the branch of mathematical logic known as recursion theory, along with Alan Turing, Emil Post, and others.
  • His worked contributed to the foundations of theoretical computer science.
  • Inventor of regular expressions in mathematics.


  • Origins of Recursive Function Theory (1981)
  • Mathematical Logic (1967)
  • The Foundations of Intuitionistic Mathematics (1965)
  • Representation of Events in Nerve Nets and Finite Automata (1956)
  • Introduction to Metamathematics (1952)

Honors and awards

  • National Medal of Science (1990)
  • Leroy P. Steele Prize (1983)
  • Numerous mathematical concepts are named after him: Kleene hierarchy, Kleene algebra, the Kleene star (Kleene closure), Kleene's recursion theorem and the Kleene fixpoint theorem.


"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."

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