We call ourselves Homo sapiens--man the wise--because our intelligence is so important to us. For thousands of years, we have tried to understand how we think: that is, how a mere handful of matter can perceive, understand, predict, and manipulate a world far larger and more complicated than itself. The field of artificial intelligence, or AI, goes further still: it attempts not just to understand but also to build intelligent entities.

To my knowledge nobody - no one who is publishing papers in the main field of AI - is even working on consciousness. I think there are some neuroscientists who are trying to understand it, but I'm not aware that they've made any progress.

You're able to use a search engine, like Google or Bing or whatever. But those engines don't understand anything about pages that they give you; they essentially index the pages based on the words that you're searching, and then they intersect that with the words in your query, and they use some tricks to figure out which pages are more important than others. But they don't understand anything.

AI's ability to recognize visual categories and images is now pretty close to what human beings can manage, and probably better than a lot of people's, actually. AI can have more knowledge of detailed categories, like animals and so on.

I expect that people are going to feel differently about that once they're aware that AI systems can watch through a camera and can, in some sense, understand what it's seeing.

Some people think that, inevitably, every robot that does any task is a bad thing for the human race, because it could be taking a job away. But that isn't necessarily true. You can also think of the robot as making a person more productive and enabling people to do things that are currently economically infeasible. But a person plus a robot or a fleet of robots could do things that would be really useful.

Leg locomotion was, for decades, thought to be an incredibly difficult problem. There has been very, very painstakingly slow progress there, and robots that essentially lumbered along at one step every 15 seconds and occasionally fell over.