George Dyson, Edge
When I started looking at the beginnings of the modern digital universe—at the origin of this two-dimensional address matrix—I became interested in the question of what had been done with it at the beginning. Of course, one of the things was the work on the hydrogen bomb.
Another thing that surprised and delighted me was to find that a Norwegian-Italian mathematical biologist and viral geneticist, Nils Aall Barricelli, had tried to come to Princeton in 1951, as soon as he heard this machine was being built. He had trouble getting a visa, so he finally shows up in early 1953 when the machine is running, and immediately begins these experiments, to see if he could inoculate this two-dimensional matrix with random strings of one-dimensional numbers that can self-replicate and cross-breed, and do all the things that we know that code does in biology, and see what happens.
And he observed. He was an observational biologist. He saw all sorts of behavior that he read all sorts of biological implications into. He was way too far ahead of the time, so no one paid attention and this was forgotten.
Just as we later worried about recombinant DNA, what if these things escaped? What would they do to the world? Could this be the end of the world as we know it if these self-replicating numerical creatures got loose?