Afterword to Konrad Zuse’s Calculating Space

There are many parallels between Zuse’s and Turing’s interests. In the mid 1930s, some researchers were engaged in what amounted to an inquiry into the nature of computation, and trying to figure out whether it would be possible to build a computing machine. In part this was a consequence of Hilbert’s programme, but it was no doubt also due to a certain chain of historical events. As pointed out by Raúl Rojas, people started to think about computers when it was time to build computers. There were of course Schönfinkel (SKI combinators), Church (λ calculus), Post (tag systems), Kleene (recursive functions), Turing (a-machines), among a few others…