and our cities could have cleaner air and rivers, and all of these things have happened andwe have healierpier andmore cheffer peaceful and more equal, if you look at the picture globally. >> because ideas have sex. now, bill gates criticized this optimism saying you fail to see that worry about the worst case can actually he drive a solution. >>guest: i donon't think that is really true. if you look where the solutions come from, they come from optimistic people living in rich people like steve jobs or leonardo in italy. they are not driven by desperation or worry. in fact, i think it is the pessimts who are the complacent ones these days because they are saying, you know this is as good as it can get. we cannot make it any better. better be careful about modified foods in indicate they are worse than existing technology. i think this world is great. but it is a veil of tears compared to what we could achieve. >> and cld achieve. so, thank you, matt ridley. coming u w wants do go into space? soon we will all be able t go there. at a dry cleaner, replaced people wi a machine. what? custome