It Began with Babbage
Read It Began with Babbage Online
Authors: Subrata Dasgupta
IT BEGAN WITH BABBAGE
THE GENESIS OF COMPUTER SCIENCE
Subrata Dasgupta
Oxford University Press is a department of the University of Oxford.
It furthers the University's objective of excellence in research, scholarship,
and education by publishing worldwide.
Oxford New York
Auckland Cape Town Dar es Salaam Hong Kong Karachi
Kuala Lumpur Madrid Melbourne Mexico City Nairobi
New Delhi Shanghai Taipei Toronto
With offices in
Argentina Austria Brazil Chile Czech Republic France Greece
Guatemala Hungary Italy Japan Poland Portugal Singapore
South Korea Switzerland Thailand Turkey Ukraine Vietnam
Oxford is a registered trademark of Oxford University Press
in the UK and certain other countries.
Published in the United States of America by
Oxford University Press
198 Madison Avenue, New York, NY 10016
© Oxford University Press 2014
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, without the prior permission in writing of Oxford University Press, or as expressly permitted by law, by license, or under terms agreed with the appropriate reproduction rights organization. Inquiries concerning reproduction outside the scope of the above should be sent to the Rights Department, Oxford University Press, at the address above.
You must not circulate this work in any other form
and you must impose this same condition on any acquirer.
Library of Congress Cataloging-in-Publication Data
Dasgupta, Subrata.
It began with Babbage : the genesis of computer science / Subrata Dasgupta.
    pages cm
Includes bibliographical references.
ISBN 978â0â19â930941â2 (alk. paper)
1. Computer scienceâHistoryâ19th century. 2. Computer scienceâHistoryâ20th century.
I. Title. II. Title: Genesis of computer science, 1819â1969.
QA76.17.D36 2014
004.09âdc23
2013023202
9 8 7 6 5 4 3 2 1
Printed in the United States of America
on acid-free paper
To Amiya Kumar Bagchi
1. Leibniz's Theme, Babbage's Dream
4
. Entscheidungsproblem:
What's in a Word?
7. A Tangled Web of Inventions
9. A Liminal Artifact of an Uncommon Nature
10. Glimpses of a Scientific Style
12. “The Best Way to Design ⦔
15. An Explosion of Subparadigms
IN RETROSPECT
, I now realize that this book on the genesis of computer science had its own genesis somewhere in my subconscious in summer 1977, when I was a visiting scientist in the Cambridge University Computer Laboratory. There, I had my first of many meetings with Maurice Wilkes, and it is also where I met David Wheeler. Twenty-eight years earlier, Wilkes, Wheeler, and their colleagues had designed and built the EDSAC, the world's first fully operational stored-program computer. As a graduate student, I had become seriously interested in the history and cognitive nature of scientific creativity, but computer science seemed different. For one thing, unlike physics, chemistry, or biology, the history of which stretched back centuries, the originators of computer science were, mostly, still living and active. When talking to Wilkes and Wheeler that summer, two pioneers, I was privy to a kind of oral history of our discipline.
Throughout the succeeding decades, my interest in the history and cognitive nature of science meandered in different directions, but I continued to think about computer science. Under the influence of Herbert Simon's
The Sciences of the Artificial
, I came to glimpse something about the nature of the discipline. I remember a conversation with B. Chandrasekaran of Ohio State University sometime during the early 1980s when we were, briefly, colleagues. Chandra said that computer science still had no intellectual tradition in the manner of physics or mathematics or chemistry. This obscurely disturbed me, but other preoccupations both within and outside computer science prevented me from pursuing this issue which, it seemed, required serious inquiry.
In November 2010, Wilkes passed away, and his death prompted me to give a lecture about him titled “The Mind of a Computer Pioneer” in the Center for Advanced Computer Studies at my university. After the talk, some graduate students approached
me to offer a seminar course on the birth of computer science. An early draft of this book formed the basis for the course, which I taught in Fall 2011.
So I am indebted to Duane Huval, Charles LeDoux, Craig Miles, and the late Michael Sharkey for stimulating me in writing this book. They were the “first responders” to its contents. Their feedback was most valuable.
I have had the good fortune of many conversations with Maurice Wilkes, and conversations and lengthy e-mail discussions with the Herbert Simon, a polymath for our times on the origins of artificial intelligence. I was also privileged to know Donald Cardwell, historian of science and technology, when I was teaching at the University of Manchester Institute of Science and Technology during the early 1990s. These encounters have shaped my thinking, in different ways, on the historical, cognitive, and creative aspects of science, especially computer science. I have no doubt that their influence on me has found its way into this book.
I thank Simon Lavington, who made available to me a scarce, historical account of the Manchester University computers and for allowing me to read an unpublished paper by him on the Manchester machines. I thank D. F. Hartley for information on the academic status of computing during its earlier days in Cambridge.
Three anonymous reviewers, who read first drafts of the first few chapters on behalf of the publisher, offered very thoughtful comments. I thank them, as well.
Thank you, Jeremy Lewis, my editor at Oxford University Press who has been with this project from the day he received my first communication. It has been a pleasure working with him.
Thanks to Erik Hane, also of the editorial staff at Oxford University Press for all his help.
Thank you Terry Grow, a young artist who produced the images that appear in this book.
Bharathy Surya Prakash supervised all stages of the physical production of the book. Her professionalism was noteworthy. I thank her and her production team.
My thanks to Oxford University Press for giving me permission to adapt two diagrams (Figure 8.5, p. 135; Figure 8.7, p. 147) from
Technology and Creativity
(1996) authored by me.
Finally, as always, thank you Mithu, Deep, and Shome.
IT BEGAN WITH BABBAGE
I
IN
1819, a young English mathematician named Charles Babbage (1791â1871) began to design a machine, the purpose of which was to compute and produce, fully of its own steam, certain kinds of mathematical tables. Thus came into being the idea of
automatic computation
âperforming computations without human interventionâand an intellectual tradition that eventually gave birth to a brand new and very curious scientific discipline that, during the late 1960s, came to be called
computer science
. This book tells the story of its genesis, a long birth process spanning some 150 years, beginning with Babbage and his dream of automatic computation.
The focus of every science (in fact, every intellectual discipline) is a certain kind of reality, a certain class of phenomena. The focus of computer science is the phenomenon called
computation
, which refers both to a concept and an activity that is associated historically with human thinking of a certain kind. The Latin root of the English word
compute
is
computare
âmeaning, reckoning, calculating, figuring out. Thus, according to etymology, computation refers to the idea and the act of reckoning or calculating.
Etymologically, then, computation's domain would seem to be the realm of numbers. However, as we will see, we have come a long way from this association. We will see that the domain of computation actually comprises
symbols
âby which I mean
things that represent other things
(for example, a string of alphabetic charactersâa wordâthat represent some object in the world, or a graphical road sign that represents a warning to motorists). The act of computation is, then,
symbol processing
: the manipulation and transformation of symbols. Numbers are just one kind of symbol; calculating is just one kind of symbol processing. And so, the focus of automatic computation, Babbage's original dream,
is whether or how this human mental activity of symbol processing can be performed by (outsourced to) machines with minimal human intervention. Computer science as the science of automatic computation is also the science of automatic symbol processing.
However, computer science is not a
natural
science. It is not of the same kind as, say, physics, chemistry, biology, or astronomy. The gazes of these sciences are directed toward the natural world. In contrast, the domain of computer science is the artificial world, the world of made objects,
artifacts
âin particular, ones that perform computations. Let us call these
computational artifacts
.
Now, the natural scientist, when practicing her science, is concerned with the world
as it is
. As a scientist she is not in the business of deliberately changing the world. The astronomer looking through a telescope at the galaxies does not desire to change the universe but to understand it, explain it; the paleontologist examining rock layers in search of fossils is doing so to know more about the history of life on earth, not to change the earth (or life) itself. For the natural scientist, to understand the natural world is an end in itself. The desire is to make nature
intelligible
.
1
The computer scientist also wishes to understand, although not through nature but through computational artifacts; however, that wish is a means to an end, for she wants to
alter
the world in some aspects by creating new computational artifacts as improvements on existing ones, or by creating ones that have never existed before. If the natural scientist is concerned with the world
as it is
, the computer scientist obsesses with the world as she thinks
it ought to be
.
