It is common to find that two traders both think their counterparts are idiotically overpaying: that is the beauty of Ricardo’s magic trick. - Matt Ridley

The fuel on which science runs is ignorance. Science is like a hungry furnace that must be fed logs from the forests of ignorance that surround us. In the process, the clearing we call knowledge expands, but the more it expands, the longer its perimeter and the more ignorance comes into view.

This led to a neat generalization, which is so tidy it ought to be true and probably would be if physicists ran the world: every animal has roughly the same number of heartbeats per lifetime. An elephant lives longer than a mouse, but its pulse rate is so much slower that, measured in heartbeats, they both live lives of the same length.

There are two ways to tell the story of the twentieth century. You can describe a series of wars, revolutions, crises, epidemics, financial calamities. Or you can point to the gentle but inexorable rise in the quality of life of almost everybody on the planet: the swelling of income, the conquest of disease, the disappearance of parasites, the retreat of want, the increasing persistence of peace, the lengthening of life, the advances in technology.