What a Computer Is—and Is Not
The digital computer began as a mathematical abstraction. Geniuses like Alan Turing and John von Neuman not only invented the abstract concepts, they also built actual computers.
Unbelievably crude by current standards, these early computers were not only proof of concept, they did important work in WWII. It was like flying a paper airplane across the ocean.
Turing’s abstraction became known as the Universal Turing Machine. It specified all digital computers. Conceptually, one digital computer is really any digital computer—it can do whatever a digital computer is capable of doing.
When I hear some idiot (Jonathan Swift called them Yahoos) say a particular computer can’t do some thing, I think, “What you mean is you don’t know how to instruct it to do that thing.”
You can say a computation takes too long or costs too much (or is not computable—another concept from Alan Turing). But you can’t offer any other excuse, except “I don’t know how.”
In addition, you can’t say a computer plays chess as a human does. It “plays” to win because it’s programmed to; it has no motivation to win because it fears losing—or enjoy winning.
A powerful computer with great software (with a team of programmers and chess experts) can “play” superior chess. Yet it can’t appreciate a brilliant chess move, even its own.
More importantly, it will never make mistakes as humans do. We have to tell computers (and pets) about mistakes, so they will not repeat them. The “oh crap” moment of a silly mistake is just as valuable as the “aha” moment of a brilliant insight
A computer is a very great invention, the greatest of all—but it is still only a thing. Mathematically, it is as great as Einstein’s E=MC2—but both are still only abstractions. Like Archimedes’ lever, a computer can move the earth, but it’s still just a tool.
No matter how powerful a tool, no computer has the potential of a human infant—who may be our next Turing or von Neuman. A computer can do anything—anything a machine can do.
A computer can’t do anything a human can do, because we don’t know everything humans can do. We have survived, coping with the unexpected, by combining creativity, imagination, and inventiveness. It’ll be a while before computers hit that trifecta.