Why People Think

Computers Can't

Marvin Minsky


Cambridge, Massachusetts

 MOST PEOPLE ARE CONVINCED computers cannot think. That is, really think. Everyone knows that computers already do many things that no person could do without "thinking." But when computers do such things, most people suspect that there is only an illusion of thoughtful behavior, and that the machine

  • doesn't t know what it's doing.
  • is only doing what its programmer told it to.
  • has no feelings. And so on.

     The people who built the first computers were engineers concerned with huge numerical computations: that's why the things were called computers. So, when computers first appeared. their designers regarded them as nothing but machines for doing mindless calculations.

Yet even then a fringe of people envisioned what's now called "Artificial Intelligence"-or "AI" for short-because they realized that computers could manipulate not only numbers but also symbols. That meant that computers should be able to go beyond arithmetic, perhaps to imitate the information processes that happen inside minds. In the early 1950's, Turing began a Chess program, Oettinger wrote a learning program, Kirsch and Selfridge wrote vision programs, all using the machines that were designed just for arithmetic.

Today. surrounded by so many automatic machines, industrial robots. and the R2-D2's of Star Wars movies, most people think AI is much more advanced than it is. But still. many `'computer experts" don't believe that machines will

 ever "really think." I think those specialists are too used to explaining that there's nothing inside computers but little electric currents. This leads them to believe that there can't be room left for anything else-like minds or selves. And there are many other reasons why so many experts still maintain that machines can never be creative. intuitive. or emotional, and will never really think, believe, or understand anything. This essay explains why they are wrong.

Can Computers Do Only What They're Told?

We naturally admire our Einsteins and Beethovens. and wonder if computers ever could create such wondrous theories or symphonies. Most people think that "creativity" requires some mysterious "gift" that simply cannot be explained. If so, then no computer can create ­ since, clearly. anything machines can do can be explained.

To see what's wrong with that, we'd better turn aside from those outstanding works our culture views as very best of all. Otherwise we'll fall into a silly trap. For, until we first have some good ideas of how we do the ordinary things ­ how ordinary people write ordinary symphonies ­ we simply can't expect to understand how great composers write great symphonies! And obviously, until we have some good ideas about that, we'd simply have no way to guess how difficult might be the problems in composing those most outstanding works ­ and then, with no idea at all of how they're made

   THE AI MAGAZINE Fall 1982      3

Introduction - Table of Contents