In the laboratory of Barnwood House Mental Hospital, on the outskirts of Gloucester, England, is a modest black contraption that looks like four storage batteries set in a square. Its only visible moving parts are four small magnets, one swinging like a compass needle over each box. Psychiatrist William Ross Ashby, who built the machine, thinks that it is the closest thing to a synthetic human brain so far designed by man.
Practical calculating machines, explains Dr. Ashby, merely take orders and act upon them, in complicated but predetermined ways. His machine, which he calls a "homeostat," is different. The present model is pretty simple, but it really thinks, he saysat least in the sense that it takes action on its own, according to any change in situation affecting it. So, for that matter, does a seesaw, compass needle, or a sunflower. Dr. Ashby contends that his machine acts in a more complicated way, adjusts itself to a greater variety of circumstances. That, he holds, constitutes thinking.
So far, the homeostat has not thought out anything very deep or complicated. When it is normal and "comfortable," says Dr. Ashby, the four magnets are centered, each above its box. By setting switches in the boxes, Dr. Ashby can make the magnets swing out of place. Then the machine is "uncomfortable," and begins at once to figure out how to get comfortable again.
To get comfortable, the machine must use 27 electrical circuits whose permutations & combinations offer 390,625 possible ways out of discomfort. The gadget is said by Psychiatrist Ashby to "think" because it quickly chooses the proper way, and soon becomes comfortable again, with all its magnets centered.
Dr. Ashby does not consider his first homeostat particularly intelligent, but he says he feels sure that a really bright model can be built on the same principle. "The method which would be used to enable it to play chess," he says confidently, "is now clear, though how long it will take to achieve this performance is uncertain."