Chapter 16 Hal

But now Texas was a tiny spot, and even the United States was hard to see. Most of Discovery's many telescopes were pointed at other planets, in the direction she was traveling. There was one, however, that looked back at Earth. It was fixed to the edge of the great dish that sent the ship's radio messages. It made sure that the dish pointed in the right direction. Messages could then come and go along a path that became more than three million kilometres longer every day.

At least once every watch period, Bowman went to the screen that showed the view from that telescope and looked back towards his home. Sometimes he saw a familiar shape, like the Pacific. And he remembered days and nights spent on its islands.

The sixth member of the crew cared for none of these things, as it was not human. It was the HAL 9000 computer, the brain and nervous system of the ship. In the 1980s, Minsky and Good had shown how it was possible to build a computer simply by designing a learning programme. In this way, an artificial brain could be grown in a very similar way to the growth of a human brain. The result was a machine that could do most things that a human brain could do, but with much greater speed and certainty.

Hal had been trained for this mission as thoroughly as his human colleagues, but in a much shorter time. His main job was to check, repeatedly, all the systems on the ship — oxygen pressure, temperature, conditions in the hibernators, and everything else that the crew depended on to stay alive. The first computers had received commandsthrough keyboards, and had replied through printers and screens.Hal could do this if necessary, but most of his communicationwas through the spoken word. Poole and Bowman could t.ilk to Hal as they would to a human being; he replied in the perfect English learned during the short weeks of his electronic childhood.

The question of whether Hal could actually think had been answered by the British mathematician Alan Turing back in the 1940s. Turing had explained that if you had a long conversation with a machine, and you could not tell if it was a machine or a man, then the machine was thinking. Hal could easily pass the Turing test.