A number of thinkers claim that there is an intrinsic difference between the human mind and a machine. John Searle developed a famous argument known as the Chinese Room, which shows that understanding a language is different from looking up constituent characters or words in a reference table. Then there is Thomas Nagel’s famous essay, “What it is like to be a bat?” which argues there is something irreducible about conscious experience, often called qualia, which means that the experience cannot be captured mechanically. Hubert Dreyfus argues that machines cannot replicate human thought because ideas are analogs and are embodied within a broader context.
These arguments point to an inherent difference between the human mind and machines, a qualitative line. But where precisely this line lies is not pinned down. As a result, while the arguments are certainly appealing on an intuitive level and can be persuasive, they lack scientific grounding. They do not result in a hypothesis that can be examined and tested.
Is there is a scientific line between mind and machine? That is, can we measure the difference between what minds and machines can do? Near the end of his life, computer pioneer John von Neumann (1903–1957) began to evaluate the differences. At that point in computer technology, there was a significant difference in processing efficiency.1