Computer Science Is Not About Computers, Any More Than Astronomy Is About Telescopes

Edsger W. Dijkstra? Alan Perlis? Jacques Arsac? George Johnson? Donald Knuth? Matthew Dennis Haines? Anonymous?

Dear Quote Investigator: Computers are the fundamental tool employed within the field of computer science; however, the discipline transcends this tool. Here are three attempts to articulate this viewpoint:

Computer science is no more about computers than astronomy is about telescopes.

Biology Is not about microscopes, and computer science is not about computers.

“Computer science” is a terrible name. Astronomy is not called “telescope science”, and biology is not called “microscope science”.

This saying has been attributed to Dutch computer scientist Edsger W. Dijkstra. Would you please explore this topic?

Quote Investigator: The earliest close match located by QI appeared in the 1986 book “Machinery of the Mind: Inside the New Science of Artificial Intelligence” by science journalist George Johnson. The attribution was anonymous. Boldface added to excerpts: 1

The possibility of a science in which all the world is thought of computationally casts the study of computers in an important new light. As its practitioners are fond of saying, computer science is not about computers, any more than astronomy is about telescopes, or biology about microscopes. These devices are tools for observing worlds otherwise inaccessible. The computer is a tool for exploring the world of complex processes, whether they involve cells, stars, or the human mind.

This saying has been difficult to trace, and this article only presents a snapshot of current research. There is evidence that the underlying notion emerged in the 1960s and 1970s, but the initial formulations were not concise and direct.

Below are additional selected citations in chronological order.

In 1971 computer scientist Anthony Ralston published “Introduction To Programming and Computer Science”. He presented a thematically pertinent analogy based on astronomers and telescopes: 2

Computer science is not alone among the sciences in its dependence upon a particular machine or device; astronomy comes immediately to mind. But just as astronomers often engage in theoretical studies which do not require a telescope, research in computer science does not necessarily involve computers directly. One such area of computer science is automata theory.

In 1974 Australian computer scientist W. N. Holmes published “The Social Implications of the Australian Computer Society”, and he criticized the phrase “computer science”: 3

However, if one is precise, the two terms computer and science are incompatible because computer is not an adjective to be applied to a discipline. Grammatically, computer science should be contrasted to physical science, natural science, and medical science.

As well as grammatically, the ill-usage can be seen by considering why there is not a telescope science embracing astronomy, surveying, and fire-spotting, or a microscope science embracing biology, metallurgy, and philately, or a telephone science embracing salesmanship, management and espionage. In other words, a science should not be circumscribed by the applicability of one of its instruments.

In 1982 “Annals of the History of Computing” printed an interview with prominent computer scientist Donald Knuth. He suggested that people in the field called computer science were drawn together because of their “peculiar way of thinking”: 4

But being a useful tool is not enough in itself to account for the fact that computer science is now thriving in thousands of places. For example, an electron microscope is a marvelous tool, but “electron microscope science” has not taken the world by storm; something other than the usefulness of computers must account for the rapid spread of computer science.

What actually happened was that the people who got interested in computers started to realize that their peculiar way of thinking was shared by others, so they began to congregate in places where they could have people like themselves to work with. This is how computer science came to exist.

In 1986 journalist George Johnson included an anonymous instance of the saying in the book “Machinery of the Mind” as mentioned previously.

In 1989 an interview with prominent French computer scientist Jacques Arsac appeared. Arsac credited the saying to computer scientist Alan Perlis with a date of 1968. The passage in French below is followed by an English translation: 5

J’ai un texte de Perlis datant de 1968 dans lequel il critique le terme de Computer Science en disant qu’il est mal fait, qu’il n’y a pas de science d’un instrument, que l’informatique n’est pas plus la science des ordinateurs que l’astronomie n’est celle des télescopes. Il y avait cette prise de conscience: une science nouvelle apparaît. Le nom est peut-être mal choisi, mais c’est une science nouvelle.

I have a text from Perlis dating from 1968 in which he criticizes the term Computer Science by saying that it is faulty, that there is no science of an instrument, that computer science is no more the science of computers than astronomy is that of telescopes. There was this realization: a new science is emerging. The name may not be well chosen, but it is a new science.

In 1993 the Department of Computer Science of Colorado State University released a technical report containing the Ph.D. dissertation of Matthew Dennis Haines. The epigraph of chapter two attributed the saying to Edsger W. Dijkstra: 6

Computer Science is no more about computers than astronomy is about telescopes.
— E. W. Dijkstra

In 1995 the textbook “C++: An Introduction to Computing” by Joel Adams, Sanford Leestma, and Larry Nyhoff contained a germane passage: 7

The term “computer science” has been the source of much confusion. Although there are sciences called physics and biology, there are not disciplines called “telescope science” or “microscope science.” How can there be a “computer science” if a computer is simply another scientific tool or instrument?

In conclusion, the earliest published evidence of a close match appeared in George Johnson’s 1986 book, but the attribution was anonymous. In 1974 W. N. Holmes made a similar point in an article published in “The Australian Computer Journal”. But he did not present a compact and direct statement.

There is indirect evidence from Jacques Arsac who stated in 1989 that he read the saying within a manuscript from Alan Perlis dated 1968. But the manuscript was never published. Thus, this claim depends on the accuracy of Arsac’s memory.

Image Notes: Public domain picture of the NASA Hubble Space Telescope; credit NASA. Image has been cropped and resized.

(Great thanks to Michele De Russi whose inquiry led QI to formulate this question and perform this exploration. Michele De Russi told QI about the valuable 1989 citation from Jacques Arsac and other citations from Arsac.)


  1. 1986, Machinery of the Mind: Inside the New Science of Artificial Intelligence by George Johnson, Chapter 4: The Art of Programming, Quote Page 81 and 82, Times Books: A Division of Random House Inc., New York. (Verified with hardcopy)
  2. 1971, Introduction To Programming and Computer Science by Anthony Ralston, Chapter 1: Introduction, Quote Page 2, McGraw-Hill Book Company, New York. (Verified with scans)
  3. 1974 November, The Australian Computer Journal, Volume 6, Number 3, The Social Implications of the Australian Computer Society by W. N. Holmes (Systems Development Institute, IBM Australia), Start Page 124, Quote Page 126, Published for the Australian Computer Society, Melbourne, Australia. (Verified with scans)
  4. 1982 July, Annals of the History of Computing, Volume 4, Number 3, A Conversation with Don Knuth by Donald J. Albers and Lynn Arthur Steen, (Reprinted from “Two-Year College Mathematics Journal”), Start Page 257, Quote Page 262, Column 1, IEEE Computer Society. Los Alamitos, California. (Verified with scans)
  5. 1989, Jacques Arsac, Un Informaticien: Entretien avec Jacques Vauthier (Jacques Arsac, A Computer Scientist: Interview with Jacques Vauthier), Quote Page 17, Published by Beauchesne. Paris. (Google Books Preview)
  6. Date: August 5, 1993, Technical Report CS-93-110, Document: Ph.D. Dissertation, Title: Distributed Runtime Support for Task and Data Management, Author: Matthew Dennis Haines, Chapter 2: Background, Quote Page 4, Institution: Department of Computer Science of Colorado State University. (Accessed via on April 2, 2021) link
  7. 1995, C++: An Introduction to Computing by Joel Adams, Sanford Leestma, and Larry Nyhoff, Chapter 1: The Science of Computing, Quote Page 4, Prentice Hall, Englewood Cliffs, New Jersey. (Verified with scans)