Sign In

Communications of the ACM

Historical reflections

Von Neumann Thought Turing's Universal Machine was 'Simple and Neat.': But That Didn't Tell Him How to Design a Computer

John von Neumann with the EDVAC

Computer architecture and theoretical computer science have different roots. Architecture grew out of projects begun in the 1940s to design high-speed electronic computing machines able to complete elaborate sequences of operations without human intervention. Its symbolic founding text is John von Neumann's 1945 "First Draft of a Report on the EDVAC,"a though early computer builders relied more directly on a series of lectures and reports disseminated the next year. Theoretical computer science grew from an academic desire to theorize about the fundamental characteristics and capabilities of automatic computing. The theoretical foundation of computer science was laid during the late-1950s and 1960s using intellectual materials scavenged from different fields. Alan Turing's 1936 paper, "On Computable Numbers, With an Application to the Entscheidungsproblem" provided the most prominent building block. In it, Turing introduced a definition of computability based on the operations of imaginary automata.

Popular imagination only has room for one "great man" per invention, and Turing's prominence in computer science has created a market for arguments that he must therefore have invented the computer itself. The fact that Turing and von Neumann knew each other has led to considerable speculation about the possible influence of Turing's paper on von Neumann's architectural approach. Yet no hard evidence has yet come to light showing that von Neumann had read or appreciated Turing's paper during the crucial period from early 1945 to mid-1946.


No entries found

Log in to Read the Full Article

Sign In

Sign in using your ACM Web Account username and password to access premium content if you are an ACM member, Communications subscriber or Digital Library subscriber.

Need Access?

Please select one of the options below for access to premium content and features.

Create a Web Account

If you are already an ACM member, Communications subscriber, or Digital Library subscriber, please set up a web account to access premium content on this site.

Join the ACM

Become a member to take full advantage of ACM's outstanding computing information resources, networking opportunities, and other benefits.

Subscribe to Communications of the ACM Magazine

Get full access to 50+ years of CACM content and receive the print version of the magazine monthly.

Purchase the Article

Non-members can purchase this article or a copy of the magazine in which it appears.
Sign In for Full Access
» Forgot Password? » Create an ACM Web Account