The question that will decide our destiny is not whether we shall expand into space. It is: shall we be one species or a million? A million species will not exhaust the ecological niches that are awaiting the arrival of intelligence.

It's as great a part of the human adventure to invent things as to understand them. John Randall wasn't a great scientist, but he was a great inventor. There's been lots more like him, and it's a shame they don't get Nobel Prizes.

Many of the technologies that are now racing ahead most rapidly, replacing human workers in factories and offices with machines, making stockholders richer and workers poorer, are indeed tending to accentuate the existing inequalities in the distribution of wealth.

The marketplace judges technologies by their practical effectiveness, by whether they succeed or fail to do the job they are designed to do.

Since stepping down as laboratory director in 1999, I have devoted an increasing fraction of my time to international issues. I am involved with energy, environment, and sustainability issues, particularly as they involve new energy sources free of greenhouse gases.

We won't be able to stop disasters from happening. On the contrary, climate change may increase the frequency and severity of floods, droughts and storms. But we are better equipped today to prepare for them and reduce their impact.

I think the kind of landscape that you grew up in, it lives with you. I don't think it's true of people who've grown up in cities so much; you may love a building, but I don't think that you can love it in the way that you love a tree or a river or the colour of the earth; it's a different kind of love.

In terms of environmental impact, Samasource jobs are very green. Our product is human intelligence, and it's transported through the Internet rather than via carbon-intensive trucking, shipping, and warehousing.