Who invented the computer? In Germany people like to say: It was Konrad Zuse. There is no such thing as a “superfather”. Today’s computer carries the genes of many fathers. John von Neumann, for example, also provides crucial ideas.

There are many reasons to build an “automatic computer”: for example, laziness. The engineering student Konrad Zuse, born on June 22, 1910, openly admitted in the 1930s that he was simply too lazy to do arithmetic. And that motivates him to build a machine that does it for him.

Mechanical main memory: wanted for lazy people

In 1935 he started to work in his parents’ living room in Berlin-Kreuzberg: since he hardly had any money, he had to improvise, his son Horst Zuse remembers.

“These were metal sheets that he bought in a junk shop and students helped him with a jigsaw to saw the cut-outs out of these metal sheets.”

Horst Zuse, son of Konrad Zuse

Zuse uses such metal sheets and steel pins to create a mechanical working memory in which numbers can be stored and read out again.

Konrad Zuse’s contribution: Calculating with zero and one

Particularly interesting: Zuse relies on the binary system right from the start. His machine shouldn’t calculate with ten fingers like a human, but only with “yes” and “no”, with zero and one. For example, with sheet metal rails that you slide forwards and backwards. So realized in his first experiment: the Z1 – which, however, still has some teething problems. Eventually, he discovers the post office’s discarded telephone relays as a cheap, reliable alternative.

12. May 1941: Presentation of the Z3 computer

Replica of Konrad Zuse’s Z3 calculator

So Zuse builds his computer with material from the garbage can. And yet the Z3 will be a milestone. On May 12, 1941, he officially presented it: the “first fully automatic, freely programmable, program-controlled computer system in the dual system.”

Zuse three years faster than US competition

Zuse is clearly ahead. Even before computer pioneers such as Howard Aiken in the USA, who also built an electromechanical computer, the Mark I. This was not completed until three years later in 1944 in Harvard.

Bombs destroy Konrad Zuse’s Z3 calculating machine

But when Zuse presented his computer, the Second World War was raging. Zuse’s Z3 perishes in the hail of bombs on Berlin and he can just save the successor machine, the Z4, dismantled on a military truck from the Allies to southern Germany. In 1945 he is sitting in Hinterstein in the Allgäu and still thinks he has concepts that go far beyond what everyone else has.

The Z4 calculating machine is now in the Deutsches Museum in Munich, which is expected to be renovated by 2028.

But even then, the computer industry was very fast-moving. Innovations have a short expiration date: in the meantime, a certain John von Neumann, then a professor at the Institute for Advanced Study (IAS) in Princeton, formulated the concept of an electronic computer that calculated in one day what it would have taken years for Zuse’s computer to calculate.

John von Neumann – exceptional mathematical talent

John von Neumann was born in Budapest in 1903 and was the son of a Jewish banker. His talent for mathematics was evident from an early age. In the 1920s, von Neumann studied chemistry in Berlin and Zurich at the same time and was a doctoral student in mathematics in Budapest. After a few years of teaching as a private lecturer in Germany, von Neumann went to the USA as a visiting professor for mechanical physics from 1930 to 1933. He stayed there and got a professorship in Princeton, New Jersey, where Albert Einstein last worked. John von Neumann is considered one of the greatest mathematicians of the 20th century. And his second wife also went down in history: Klara Dan von Neumann was a computer scientist and one of the first computer programmers.

First electronic US general purpose computer ENIAC: a tube monster

US mainframe computer ENIAC

In the USA, too, people are struggling with problems that cannot be solved with the old slide rules. For example in the Los Alamos project. There, from 1943, John von Neumann worked together with Robert Oppenheimer on a common goal: to develop an atomic bomb before the Nazis did. But Neumann urgently needs a computer for the complex model calculations. In 1944 he therefore joined the so-called ENIAC team. ENIAC stands for Electronic Numerical Integrator and Computer. It is the first general purpose electronic calculator developed at the University of Pennsylvania by computer pioneers Presper Eckert and John Mauchly. It is funded by the US Army. Although the computer has already been designed, Neumann uncovers weak points and makes suggestions for improvement.

John von Neumann and his principles shape computer science textbooks

Mathematician John von Neumann in 1954

For example, if the engineers want to reprogram the ENIAC, they have to almost rebuild the computer. It’s a tedious business. Above all, Neumann therefore demands a uniform, flexible memory in which the program and data can be stored. Neither Zuse nor the pioneers in the USA had implemented it that way up until then. Neumann notes all of his results in a “First draft of a report”. This report becomes a kind of bible for computer construction. Although many colleagues had similar ideas about the architecture and functioning of computers, nobody had summed them up so ingeniously. As “von Neumann principles” they characterize all computer science textbooks to this day and the blueprints for today’s computers.

This means: Zuse’s computers are not a direct model for the electronic machines of the post-war period. At that time it was necessary to solve problems that Zuse had not solved. The scientific community looks to the USA, not to the Allgäu. Not to Zuse, but to the treatises of a John von Neumann.

The computer – who invented it?

Inventor Konrad Zuse in 1989

Konrad Zuse is not a scientist like von Neumann. He is an inventor-entrepreneur who also builds his machines himself in order to sell them. But he never gets a computer patent. Zuse makes a lot of applications, but he doesn’t have any good advisors and therefore, after many years of fighting and arguing about recognition, comes away empty-handed, recalls his son Horst Zuse: “In 1967, the Federal Patent Court determined that progress was recognised, the novelty is recognized, but the level of invention is rejected.” This is a catastrophe for Konrad Zuse. In the end, it’s no longer about financial interests, but about honor:

“He himself would not have had any more of the patent if he had received it because Zuse KG had already passed over the patents to Siemens.”

Horst Zuse, son

Tubes were used in the Z22 mainframe computer from Zuse AG.

Despite the defeat, Konrad Zuse was happy to present himself as the inventor of the computer. From time to time, the myth of the unrecognized inventor genius arose, which does not come up against foreign interests. In fact, in the USA, it was simply impossible to imagine that they themselves invented Google, the Internet, the microchip and the PC. But the computer should come from Germany of all places, from the land of the former Nazis?

“The inventor of the computer does not exist. Engineers and scientists in Germany, England and the USA have contributed with their ideas and developments to the machine that we now understand as a computer and that is the stored-program one electronic machine, which Neumann actually defined in 1945.”

Ulf Hashagen from Deutsches Museum

Invention of the computer – a historical process

The bottom line is that the invention of the computer – like the invention of photography – was a complicated historical process. In the place of a great father, you can put any number of pioneers, co-thinkers and parallel thinkers who often knew nothing about each other. Even if the longing for the one shining hero is traditionally great, and scientists also long for identification figures.

Computer History – What if?

Statue of Konrad in Hünfeld, Hesse, where he lived for forty years.

And what would have happened if Zuse had decided to become a baker or a landscape gardener? How might the history of the computer have changed? Would today’s computers look different then? Hardly likely. Which doesn’t mean that Zuse’s genes aren’t somehow embedded in today’s computers. It’s not just a father’s genes. There are many genes from many fathers.

• IQ – Science and Research” reported on May 12, 2016 about “How Konrad Zuse built a computer from ‘waste parts'” and on June 22, 2010 about the “fathers of the computer”. li>