It is easy to confuse the concepts of "virtual reality" and a "computerized model of reality (simulation)". The former is a self-contained Universe, replete with its "laws of physics" and "logic". It can bear resemblance to the real world or not. It can be consistent or not. It can interact with the real world or not. In short, it is an arbitrary environment. In contrast, a model of reality must have a direct and strong relationship to the world. It must obey the rules of physics and of logic. The absence of such a relationship renders it meaningless. A flight simulator is not much good in a world without aeroplanes or if it ignores the laws of nature. A technical analysis program is useless without a stock exchange or if its mathematically erroneous. Yet, the two concepts are often confused because they are both mediated by and reside on computers. The computer is a self-contained (though not closed) Universe. It incorporates the hardware, the data and the instructions for the manipulation of the data (software). It is, therefore, by definition, a virtual reality. It is versatile and can correlate its reality with the world outside. But it can also refrain from doing so. This is the ominous "what if" in artificial intelligence (AI). What if a computer were to refuse to correlate its internal (virtual) reality with the reality of its makers? What if it were to impose its own reality on us and make it the privileged one? In the visually tantalizing movie, "The Matrix", a breed of AI computers takes over the world. It harvests human embryos in laboratories called "fields". It then feeds them through grim looking tubes and keeps them immersed in gelatinous liquid in cocoons. This new "machine species" derives its energy needs from the electricity produced by the billions of human bodies thus preserved. A sophisticated, all-pervasive, computer program called "The Matrix" generates a "world" inhabited by the consciousness of the unfortunat...
