The more you enter, the more you become locked in. Your social-networking site becomes a central platform - a closed silo of content, and one that does not give you full control over your information in it. The more this kind of architecture gains widespread use, the more the Web becomes fragmented, and the less we enjoy a single, universal information space.

You can’t propose that something be a universal space and at the same time keep control of it.

One way to think about the magnitude of the changes to come is to think about how you went about your business before powerful Web search engines. You probably wouldn't have imagined that a world of answers would be available to you in under a second. The next set of advances will have an different effect, but similar in magnitude.

The world's urban poor and the illiterate are going to be increasingly disadvantaged and are in danger of being left behind. The web has added a new dimension to the gap between the first world and the developing world. We have to start talking about a human right to connect.

E-mail is interesting. We can't live with it, and you can't live without it.

The Web as I envisaged it, we have not seen it yet. The future is still so much bigger than the past.

In many ways, people growing up with the Web and now the Semantic Web take the power at their fingertips for granted.