The Rational Optimist
At the base of Ridley's argument is the benefit of trade, or 'ideas having sex' if you look at it from a different point of view. He claims that when humans started to trade is when they started on the road to becoming modern humans, and that trade has been benefiting humankind ever since. He also points out how standards of living invariably drop when governments decide to manage their people's affairs too closely. As for those who predict disaster - well Ridley gives plenty of examples of similar predictions in the past which have invariably turned out to be wrong.
It's a persuasive argument, but I felt that Ridley's seemed too keen to trust to the free market, and didn't leave any space for the careful deliberation which is necessary to make sure we are on the right track. For instance he criticises George Orwell and Aldous Huxley despite the fact that their message seems to be the same as his - a warning about too much state intervention. They're pessimistic and so must be wrong.
In summary, the book is well worth reading, but don't let it stop you thinking things out for yourself.