I Current Comments” EUGENE GARFIELD lNSTITUIE FM SCIENTIFIC WFOFMATIOW 3S)1 MARKET ST PW.ADEL$?+IA PA 19104 John von Neumann, John Mauchly, and the Invention of the Modern CosnputeK A Story of Genius and Controversy Number 9 March 4, 1991 My friend Fred Koehen 1 often spoke about the excitement of working with John von Neumann-a near-mythical figure in the development of the computer. Many of us would have enjoyed meeting this histori- cal figure. So, I was quite pleased to read a recent article in the Anrerican Heritage of Invention & Technology 2 that linked von Neumann’s life and work with another com- puter pioneer, John Mauchly of the Univer- sity of Pennsylvania%with whom I had con- siderable contact during my career. Mauchly and I fmt met at Johns Hopkins in 1951, and, from then on, periodically until the time of his death in 1980. In fact, during his failing years, we provided him with regular literature updates on the bkroci disorder from which he was suffering. In many ways, Mauchly was a tragic fig- JohnvonNeumann ure. Various disputes about who invented Courtesy Archives, Insti[uic for Advanced Sudy, Rmceton the computer at UNIVAC probably added to the stress of his life. Nevertheless, I also feel compelled to re- Heppenheimer, a free-lance science writer port that it was indeed Univac that provided and most recently author of The Coming the vehicle for the experiments I executed Quake: Science and Trembling on the Cali- for my doctoral dissertation. With the help fornia Earthquake Frontier (llrnes Books, of John O’Connor, I ran the fmt programs 1988). Illuminating the time before hard- involving computerized translation of ware and software, the author has vividly chemical nomenclature.3,4 captured how a handful of brilliant mathe- I believe readers of Current Contents@ maticians visualized the future. will enjoy the following article by T.A. 91991 L9 REFERENCES 1. Garlktd IL Msnfred Knchur: in memory of an information scientist pioneer qus world brairr-ist. Curreru Coruents (25):3-14, 19 June 1989. 2. Ileppemhelrner T A. How von Neumann showed the way. Anrez Heritage Invent Techrrd. 6(2)8-16, 19S0 3. Gar&fd E. Chemic&lirrguistics: computer translation of chemical nomenclature. Nan#e 192:192, 1%1. (Reprinted im Essays of an infonnotion scierukt. Phitadelphizx 1S1Press, 1984. Vol. 6. p. 4S9-91.) 4---------- . History of citation indexes for chemistry: a brief review. J. Chem. Inform. Comput, Sci. 25:170-4, 1985. (.Reprinted in: [bid, 1988. vol. 9. p. 42-7.) 32 Reprinted with permission from: American Heritage of Invention& Technology 6(2) S-16, 1990. How VOSINeumann Showed the Way By T. A. Heppeaheimer here were ten people in the pasty, programs of wide variety. Such machines and they were about to descend would be highly flexible, readily shifted into the Grand Canyon. The from one task to another. They could react T guide wore a cowboy hat and intelligently to the results of their calcula- leather chaps; a coil of rope hung from his tions, could choose among alternatives, and saddle. Most of the others were dressed for could even play checkers or chess. a day outdoom, wearing hats, loose-fitting This represented something unheard ofi a shirts, and the like. At the rem of the group machine with built-in intelligence, able to was John von Neumann-hatless and in the operate on internal instnsctions. Before, formal suit and tie of a banker. Moreover, even the most complex mechanisms had al- while everyone else sat on a mule facing ways been controlled from the outside, as right, his faced left. by setting dials or knobs. Von Neumann did Von Neumann had been following his not invent the computer, but what he intro- own rules for years. He owned a photo- duced was equally significant: computing graphic memory that held the complete by use of computer programs, the way we texts of works of Iiteratmt and one of the do it today. world’s largest collections of off-color lim- The roots of this invention lay not in elec- ericks. Yet he would phone home to ask his tronics but in the higher reaches of mathe- wife to help him remember an appointment. matics, in a problem that tantalized special- He loved to throw parties-and sometimes ists in mathematical logic during this would steal away to work in his office while century’s earl y decades: the challenge of es- his guests remained downstairs. Among his tablishing basic foundations for math. These friends he was nearly as well known for his would take the form of an explicit set of trtilc accidents as for his accomplishments definitions and axioms, or timdamental in mathematics. A strong supporter of the statements, ftom which all known results military, he was fond of attending nuclear- might be derived. weapons tests. He died of cancer at the age Everyone expected that such foundations of f~-three. could be constructed if people were only Through it all, he was one of the century’s clever enough. David Hilbert of Gbttingen most creative and productive mathemati- University, widely regarded as the world’s cians, lifting his intellectual scepter across a leading mathematician, summarized this host of technical fields. Mostly he worked viewpoint in a 1900 address: “Every mathe- with pencil and paper, but in the years tier matical problem can be solved. We are all 1945, for the fmt time in his life, he set convinced of that. Atler all, one of the himself the task of managing the design and things that attracts us most when we apply construction of a piece of equipment. This ourselves to a mathematical problem is pre- was the Institute for Advanced Study com- cisely that within us we always hear the call: puter, and it set the pattern for subsequent here is the probiem, search for the solutiosu computers as we know them today. you can find it by pure thought, for in math- What distinguished this IAS machine was ematics there is no ignorabimus [we will programmability. It embodied von Neumann’s not know] .“ insistence that computers must not be built In fact, however, a powerful ignoralimus as glorified adding machines, with all their lay at the center of the problem of mathe- operations specified in advance. Rather, he matical foundations. The man who demon- dec@e~ they should be built as general- strated this was Kurt Goedel, a logician at puspose logic machines, built to execute the University of Vienna. He was a smallish 33 man with an earnest expression and a thick worthless in World War II, he withdrew his pair of glasses; he appeared even smaller savings and purchased two ingots of silver, than he was because of his reluctance to eat. buried them in his yard-and then failed to Psychological depressions and other ill- draw a suitable treasure map that would per- nesses dogged him throughout much of his mit him to fmd them. And when his bicycle life, made more serious at times by his dis- developed the habit of having its chain tnrst of doctors. In contrast with the gregari- come loose, he refused to take it in for re- ous and hearty von Neumann, Goedel was pairs. Instead he trained himself to estimate solitary in his habits, but he did form a few when this was about to happen so he could close relationships. One was his lifelong make timely preventive fixes by himself. marriage to Adele Nimbursky, a former cab- urirsg was a twenty-five-year-old aret damxr. Another was a warm friendship undergraduate when he made his with Albert Einstein. major contribution to computer In two epmhal Paprs, published in 1931, T science. It came in a 1937 paper, when he was twenty-five, Goedel showed “On Computable NmnbersU in which he that no foundations could be constructed. specifically dealt with an imaginary version More particularly, he showed that if anyone of the computer. This idealized machine was tried to set forth such foundations, it would to follow coded instructions, equivalent to be possible to devise mathematical state- computer programs. It was to deal with a ments that were “formally undecidable”— long paper tap that would be marked off in incapable of being proved or disproved squares, each square either black or white using the propmd foundations. Anil and thus representing one bit of information. Nerode of Cornell University descrkm this On this tape, in response to the coded com- conclusion as “the paper that everyone read mands, the machine would execute a highly because it was the most signal paper in logic limited set of operations: reading, erasing, in two thousand years.” or marking a particular square and moving In particular, this work offered two major the tape. rtsults for the eventual development of Analyzing this idealized computer, Turing computer science. To prove his theorems, proved that it offered properties closely re- Goedel introduced a notation whereby state- lated to Goedel’s concept of formal un- ments in mathematical logic were encoded decidability. What was important for com- as numbers. Every such statement could be puter science, however, was another expressed as an integer, usually a very large realization: that with sufficiently lengthy one, and every integer corresponded to a ctied instructions this simple machine statement in logic. This introduced a con- would be able to carry out any computation cept that would be key to the later advent of that could be executed in a finite number of computer programming: that not only nu- steps. Here, in its essential form, was the merical data but also logic statements-and concept of a general-purpose programmable by extension, programming instructions- computer.