I agree with people like Richard Dawkins that mankind felt the need for creation myths. Before we really began to understand disease and the weather and things like that, we sought false explanations for them. Now science has filled in some of the realm – not all – that religion used to fill.

So we can simulate Richter-10 earthquakes. We simulate 70-foot waves coming into these things. Very cool. We basically say no human should ever be required to do anything, because if you judge by Chernobyl and Fukushima, the human element is not on your side.

In fact, batteries haven't improved over the last 100 years as much as they would need to in order to make that happen. So I'm invested in a lot of battery companies - and there's a lot that exists I'm not in. They're all having a tough time achieving it.

I watched the piles of feces go up the conveyor belt... They made their way through the machine... A few minutes later I took a long taste of the end result: a glass of delicious drinking water.

Vaccination is pretty special because you can do a vaccination campaign anywhere in the world. All you are doing is gathering women from the villages, getting them the vaccines and asking them to go around and find the children.

At Microsoft there are lots of brilliant ideas but the image is that they all come from the top - I'm afraid that's not quite right.

Vaccines are a miracle; they're fantastic. Anything that makes people hesitate to give their children these vaccines according to the recommended schedule creates risk. Risk for the children who don't get vaccinated and risk for children, some of whom don't have an immune system, so they're benefiting from the fact that the community protection means the disease doesn't get to them.