THE competition was intense. Move by countermove, the opponents were battling it out over the chessboard. But they were not ordinary chess players. On one side was the world computer chess champion Cray Blitz. On the other side was the challenger Hitech. Both of them were specially programmed supercomputers, running on different programs. And both of them were powerful enough to outplay all but the topranking human chess players. They were engaged in the world computer championship title match.

By the final round, Hitech gained the upper hand, as everyone had expected. It needed only a draw to win. But to everyones surprise, Hitech failed to notice a subtle move Cray Blitz was developing. Suddenly, Cray Blitz came from behind and defeated Hitech, retaining its world championship.

Stories like this tend to leave some people feeling uneasy. It is somehow unnerving to learn that computers have become better than most humans at playing chess, solving puzzles, or proving mathematical theorems; that there are robots that can hear, see, and even talk; or that doctors consult computers for opinions on treatment or diagnosis. Is science fiction coming true? Have computers become so smart that they will soon be masters of the world?

Such concerns are justifiable because we normally associate activities like problem solving and use of language with intelligence. We do not expect machines to do these thingsnot even computers because ordinary computers are no more than highspeed information processors that respond to commands. But computers like Hitech and Cray Blitz are far from ordinary. To describe what they are trying to make such computer systems do, scientists have coined the term artificial intelligence, or AI. And the claims and predictions they have made for these machines have not helped to calm the uneasiness.

In 1957 Herbert Simon, now a Nobel laureate, predicted: Within 10 years a digital computer will be the worlds chess champion. More recently, computer scientist Harvey Silverman of Brown University in Providence, Rhode Island, claimed that in a few years we expect to develop [a computer] that will have a vocabulary of 5,000 words and will understand most conversations in plain English. Really, is the human mind becoming obsolete?

What Is Artificial Intelligence?

To reason, to understand, to discover meaning, to deal with unfamiliar circumstances, and to make decisionsthese are things usually associated with the human mind. The ability to do these and many other tasks is what intelligence is all about. Ever since the 17th century, scientists have been dreaming of a thinking machine that could solve mathematical and logical problems. However, it was not until the advent of the electronic computer in the mid1950s that the dream began to take on substance.

Most of us are familiar with the computers ability to store, retrieve, and process large amounts of information at great speed. Because of this, computers are used in accounting and bookkeeping; handling files, catalogs, indexes, and so forth. In all these operations, raw data is fed into the computers memory, and the computer is given a set of instructions, or program, on what to do with the data. In a computer used for accounting, for example, the machine may be programmed to process all the information at the end of the month to produce bills and statements for all the accounts.

Of course, it takes a certain kind of intelligence to do the kind of work described. Essentially, however, such systems merely follow a predetermined set of steps, specified by humans, until the job is accomplished. If something is missing or has gone wrong during the course of operation, the machine stops and waits for further instructions from the human operator. Such machines can be said to be efficient but hardly intelligent. Computers with artificial intelligence, though, are to be a different breed.

Basically, artificial intelligence is a set of instructions, or programs, that attempts to enable a computer to solve problems on its ownthe way a human does. In one approach, rather than follow a spelledout, stepbystep procedure that leads to the solution, the computer tackles the problem by trial and error. The result of each trial is analyzed and used as the basis for working out the next trial.

This principle may sound simple in itself, but when it is applied to reallife situations, things can become very complicated. Why? Because few things in real life are as simple as yes or no, black or white. Rather, everything is full of shades of meanings and subtle implications. For example, if a certain medical procedure is to be recommended only for patients over six years of age, what about a child five years and ten months old? Such decisions are far beyond what todays computers can handle. However, if the field of application is restricted, AI can be successfully applied.

For example, armed with artificial intelligence, Hitech was able to defeat some of the better chess players all on its own, without any external, human direction or intervention. But how does it do this? The computer carefully examines the opponents move, then searches through the thousands of positions in its memory to come up with the countermove that would minimize the opponents potential for gain. To do this, it checks through 175,000 chess positions every second, or over 30 million positions in the three minutes it usually takes to come up with the right move. For Games Online visit: http://www.urlife.info