Are robots possible, though? And if they are, are they desirable?
Mechanical devices with gears and springs and ratchets could certainly make manlike devices perform manlike actions, but the essence of a successful robot is to have it think-and think well enough to perform useful functions without being continually supervised.
But thinking takes a brain. The human being is made up of microscopic neurons, each of which has an extraordinarily complex substructure. There are 10 billion neurons in the brain and 90 billion supporting cells, all hooked together in a very intricate pattern. How can anything like that be duplicated by some man-made device in a robot?
It wasn't until the invention of the electronic computer thirty-five years ago that such a thing became conceivable. Since its birth, the electronic computer has grown ever more compact, and each year it becomes possible to pack more and more information into less and less volume.
In a few decades, might not enough versatility to direct a robot be packed into a volume the size of the human brain? Such a computer would not have to be as advanced as the human brain, but only advanced enough to guide the actions of a robot designed, let us say, to vacuum rugs, to run a hydraulic press, to survey the lunar surface.
A robot would, of course, have to include a self-contained energy source; we couldn't expect it to be forever plugged into a wall socket. This, however, can be handled. A battery that needs periodic charging is not so different from a living body that needs periodic feeding.
But why bother with a humanoid shape? Would it not be more sensible to devise a specialized machine to perform a particular task without asking it to take on all the inefficiencies involved in arms, legs, and torso? Suppose you design a robot that can hold a finger in a furnace to test its temperature and turn the heating unit on and off to maintain that temperature nearly constant. Surely a simple thermostat made of a bimetallic strip will do the job as well.
Consider, though, that over the thousands of years of man's civilization, we have built a technology geared to the human shape. Products for humans' use are designed in size and form to accommodate the human body-how it bends and how long, wide, and heavy the various bending parts are. Machines are designed to fit the human reach and the width and position of human fingers.
We have only to consider the problems of human beings who happen to be a little taller or shorter than the norm-or even just left-handed-to see how important it is to have a good fit into our technology.
If we want a directing device then, one that can make use of human tools and machines, and that can fit into the technology, we would find it useful to make that device in the human shape, with all the bends and turns of which the human body is capable. Nor would we want it to be too heavy or too abnormally proportioned. Average in all respects would be best.
Then too, we relate to all nonhuman things by finding, or inventing, something human about them. We attribute human characteristics to our pets, and even to our automobiles. We personify nature and all the products of nature and, in earlier times, made human-shaped gods and goddesses out of them.
Surely, if we are to take on thinking partners-or, at the least, thinking servants-in the form of machines, we will be more comfortable with them, and we will relate to them more easily, if they are shaped like humans.
It will be easier to be friends with human-shaped robots than with specialized machines of unrecognizable shape. And I sometimes think that, in the desperate straits of humanity today, we would be grateful to have nonhuman friends, even if they are only friends we build ourselves.
Essays Our Intelligent Tools
Robots don't have to be very intelligent to be intelligent enough. If a robot can follow simple orders and do the housework, or run simple machines in a cut-and-dried, repetitive way, we would be perfectly satisfied.
Constructing a robot is hard because you must fit a very compact computer inside its skull, if it is to have a vaguely human shape. Making a sufficiently complex computer as compact as the human brain is also hard.
But robots aside, why bother making a computer that compact? The units that make up a computer have been getting smaller and smaller, to be sure-from vacuum tubes to transistors to tiny integrated circuits and silicon chips. Suppose that, in addition to making the units smaller, we also make the whole structure bigger.
A brain that gets too large would eventually begin to lose efficiency because nerve impulses don't travel very quickly. Even the speediest nerve impulses travel at only about 3.75 miles a minute. A nerve impulse can flash from one end of the brain to the other in one four-hundred-fortieth of a second, but a brain 9 miles long, if we could imagine one, would require 2.4 minutes for a nerve impulse to travel its length. The added complexity made possible by the enormous size would fall apart simply because of the long wait for information to be moved and processed within it.
Computers, however, use electric impulses that travel at more than 11 million miles per minute. A computer 400 miles wide would still flash electric impulses from end to end in about one four-hundred-fortieth of a second. In that respect, at least, a computer of that asteroidal size could still process information as quickly as the human brain could.
If, therefore, we imagine computers being manufactured with finer and finer components, more and more intricately interrelated, and also imagine those same computers becoming larger and larger, might it not be that the computers would eventually become capable of doing all the things a human brain can do?
Is there a theoretical limit to how intelligent a computer can become?
I've never heard of any. It seems to me that each time we learn to pack more complexity into a given volume, the computer can do more. Each time we make a computer larger, while keeping each portion as densely complex as before, the computer can do more.