alan winfield, welcome to hardtalk. delighted to be here, stephen. do have a fascinating title, director of robot ethics, i'm tempted to ask you, what's more important to you, the engineering, robotics or the ethics, being an ethicist? both are equally important. i'm fundamentally an engineer so i bring an engineering perspective to robotics but more than half of my work now is thinking about... i'm kind of a professional worrior now. would you say the balance has shifted over the course of your career? you started out very much in computers and engineering but increasingly as you have dug deeply into the subject, in a sense the more philosophical side of it has been writ large for you? absolutely right. it was really getting involved in public engagement, robotics public engagement, 15 years ago that if you like alerted me and sensitised me to the ethical questions around robotics and ai. let's take this phrase, artificial intelligence. it raises an immediate question in my mind, how we define intelligence. i wonder if you could do that for me? it's