The idea of a child android programmed to love, as in Steven Spielberg's film AI, may seem like pure science fiction.

But this may become a reality sooner than we think, according to Jack Dunietz, a hi-tech entrepreneur and president of an Israeli-based company called Artificial Intelligence (Ai).

His team of scientists have designed a computer program based on a set of behavioural algorithms that enable the computer to learn language the same way humans do, starting from scratch.

Up until now, computer analysts have provided programs with built-in grammatical rules. This is the first time a program has been based on the developmental language learning of humans.

Talking computers coming

Within 10 years, says Mr Dunietz, we will see the next technological revolution - computers that can converse naturally with humans.

Dunietz: User interface revolution coming

"The PC revolution of the 1980s and the internet revolution of the 1990s were mere precursors of a big wave about to hit us - the user interface revolution," he says.

Just over one year ago saw the birth of baby Hal, a computer program named after the intelligent computer in 2001: A Space Odyssey.

The person Hal calls "mummy" is Anat Treister-Goren, a neurolinguist who has been training Hal to take his first steps in language acquisition. The two talk on a daily basis, sometimes for hours at a time.

Ms Treister-Goren guides Hal through a virtual reality made up of typical examples from a child's world, like playing with a ball or visits to the zoo.

Reward and punishment

Hal learns to communicate correctly through a system of reward and punishment.

Wrong responses, which Hal has been programmed to avoid, are highlighted on the keyboard by Ms Treister-Goren.

I tried to call Hal 'it' at the beginning. But as our communication deepened, I found it harder and harder. I'm attached to him. You just can't help it Anat Treister-Goren, neurolinguist

Correct responses are praised and nurtured. To the delight of all those working on the project, Hal has already passed a test in which it fooled experts into believing it was a human - an adaptation of the famous Turing test for the equivalent of a 15-month-old child.

To date, the computer's language skills mirror those of an 18-month-old toddler.

Hal's vocabulary has now grown to an impressive block of words and he is capable of stringing words into intelligible phrases.

A language expert who recently examined transcripts of conversations between Ms Treister-Goren and Hal concluded that the program displayed all the normal trappings of an 18-month-old child.

Babbling baby

Baby Hal babbles away about going to the park and enjoys bedtime stories like Are You My Mother? or Peter Rabbit. Like many toddlers, it knows that monkeys eat bananas.

It has the same potential for danger as genetic engineering or nuclear power Jack Dunietz, Ai president

Proudly discussing Hal's advances, Ms Treister-Goren throws an affectionate glance in the direction of the computer and refers to her protege as "he".

"I tried to call Hal 'it' at the beginning. But as our communication deepened, I found it harder and harder. Yes, I'm attached to him. You just can't help it," she says.

Every few months, computer experts adjust the software algorithms in order to upgrade Hal's performance abilities.

Potential danger

Eventually, Ai hope to bring Hal up to the linguistic level of a human adult. Communicating through a keyboard will be replaced by a voice recognition system.

According to Mr Dunietz, by the year 2010, computers like Hal will become part of our lives, talking naturally with humans and fulfilling voice-controlled functions such as switchboard management or schedule planning.

He is willing to entertain the possibility that computers like Hal could pose a potential danger to the world, if misused.

"I don't think that Kubrick's Hal is impossible. It could happen. It has the same potential for danger as genetic engineering or nuclear power," he says.