Sociable humanoid robots could soon be intelligent enough to enter the household as pets or companions, but cybernetics experts dispute the prospect of meaningful relationships ever forming between humans and their artificial chums. The possibility of a robot achieving sentience -- intelligence with the capacity for emotional development -- is a hot philosophical subject. Humans have an exceptional tendency to invest a variety of emotions in inanimate objects such as cars, houses and so on, but experts in artificial life believe the capabilities of "conscious" robots will be too limited for them to ever offer a substitute for human friendship. Sony's AIBO robot pooch, developed in 1999, proved that robots can learn how to interact with humans using limited intelligence and play a part in their daily lives, albeit at a rudimentary level. The AIBO has learning ability and the capacity to mature. It is not designed for a servile role, but rather to fulfil a "useful" purpose, primarily that of companionship. "I designed AIBO to be a friend for those older people in our society" said Toshitada Doi, president of Sony's digital creatures laboratory during Comdex in 1999. Ironically, Sony's extensive research into developing the world's first intelligent companion may have overestimated man's need for a chum endowed with brains. The emergence of seemingly "useless" artificial pets like Tamagotchis or Furbies confirmed that a relationship between people and robotic creatures is possible, even if the robot is little more than a keyring or stuffed toy with a dozen predefined functions. Nigel Shadbolt, professor of artificial intelligence at the University of Southampton is unconvinced about the role robots -- intelligent or not -- will play in our lives. "I can imagine robots becoming companions, but we are a long way from producing robots with the same behaviour and intelligence as pets." Shadbolt is sceptical about robots ever fulfilling more than a proxy role in social situations. Kevin Warwick, professor of cybernetics at Reading University, cites Sony's AIBO as the closest man has to a sentient artificial being. According to Warwick's research, robots with brain processing capabilities are no more intelligent than snails or bees, with basic behaviour patterns and the ability to map out simple environments. "Humans have human emotions and robots have robot emotions. As soon as you allow robots to learn, you are opening up the possibility that they could develop their own emotions." The hypothetical nature of sentience debates leads experts such as Dr Murray Shanahan, senior lecturer in electrical engineering at Imperial College, to completely reject the possibility of artificial pets ever possessing human emotions or responses. "Sentience is a rather high-vaulting word to describe the kind of robots that we could have in the near future. It is not appropriate to think of robots as being tied up with human biological heritage, as we're not aiming to put things that matter in robots," he says. Cybernetics experts seem unwilling to talk about the prospect of building "conscious" robots capable of experiencing pleasure or pain, as they would then be responsible for the way in which they are treated. Shanahan is adamant that robots, particularly those with sophisticated 'thought' functions, must perform a completely servile role. "I would not want to build such things where there was a moral issue involved...We're designing these things and we need to engineer them in a way that [ensures] robots never move beyond what they are programmed to do." Shanahan's argument assumes cybernetic experts will be willing to halt their research once artificial intelligence has reached a certain level of development. Shadbolt, however, is concerned that the people creating robots will have no interest in turning them off. "There will be a clear point at which we need to worry about building in safeguards against the autonomy of robots," asserts Shadbolt. "You don't have to be smarter than humans -- if it has a life of its own it procreates and becomes a pest." Warwick believes that in ten to 20 years time, humanoid robots will complicate the moral dilemma further. "In this timeframe, robots in the home will not be an equal, but they will be given more of a status." He believes that in 20 years time, robots will have an intellect on par with humans, which could reverse the issue into whether or not robots will be willing to let humans into their homes! "Intelligent robots would bring [other] intelligent robots into the home, and we could see robots ultimately making the decisions," he argues. 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