THE INHUMAN MESS OUR MACHINES HAVE GOTTEN US INTO Rodney Brooks
Rodney Brooks is a computer scientist; Panasonic Professor of Robotics, emeritus, MIT; former director, MIT Computer Science Lab; and founder, chairman, and CTO of Rethink Robotics. He is the author of Flesh and Machines.
Mathematicians and scientists are often limited in how they see the big picture, beyond their particular field, by the tools and metaphors they use in their work. Norbert Wiener is no exception, and I might guess that neither am I.
When he wrote The Human Use of Human Beings, Wiener was straddling the end of the era of understanding machines and animals simply as physical processes and the beginning of our current era of understanding machines and animals as computational processes. I suspect there will be future eras whose tools will look as distinct from the tools of the two eras Wiener straddled as those tools did from each other.
Wiener was a giant of the earlier era and built on the tools developed since the time of Newton and Leibniz to describe and analyze continuous processes in the physical world. In 1948 he published Cybernetics, a word he coined to describe the science of communication and control in both machines and animals. Today we would refer to the ideas in this book as control theory, an indispensable discipline for the design and analysis of physical machines, while mostly neglecting Wiener’s claims about the science of communication. Wiener’s innovations were largely driven by his work during the Second World War on mechanisms to aim and fire anti-aircraft guns. He brought mathematical rigor to the design of the sorts of technology whose design processes had been largely heuristic in nature: from the Roman waterworks through Watt’s steam engine to the early development of automobiles.
One can imagine a different contingent version of our intellectual and technological history had Alan Turing and John von Neumann, both of whom made major contributions to the foundations of computing, not appeared on the scene. Turing contributed a fundamental model of computation—now known as a Turing Machine—in his paper “On Computable Numbers with an Application to the Entscheidungsproblem,” written and revised in 1936 and published in 1937. In these machines, a linear tape of symbols from a finite alphabet encodes the input for a computational problem and also provides the working space for the computation. A different machine was required for each separate computational problem; later work by others would show that in one particular machine, now known as a Universal Turing Machine, an arbitrary set of computing instructions could be encoded on that same tape.
In the 1940s, von Neumann developed an abstract self-reproducing machine called a cellular automaton. In this case it occupied a finite subset of an infinite two- dimensional array of squares each containing a single symbol from a finite alphabet of twenty-nine distinct symbols—the rest of the infinite array starts out blank. The single symbols in each square change in lockstep, based on a complex but finite rule about the current symbol in that square and its immediate neighbors. Under the complex rule that von Neumann developed, most of the symbols in most of the squares stay the same and a few change at each step. So when one looks at the non-blank squares, it appears that
50
HOUSE_OVERSIGHT_016853