OVER the centuries, humans have constantly sought to increase their muscle power. Bullocks for ploughing, water currents for milling, and horses for carrying or pulling loads gave way to engines: first steam, then internal combustion, and now electric ones. Brain power, humans soon realized, was even more important. First, it set them apart and made them superior to other animals; for a while, it deluded them into thinking that it would help them to dominate nature; finally — constantly and sadly — it was a way of enslaving, exploiting, and oppressing other human beings.

Brain power increased through cumulative knowledge, passed from one to the other, teacher to student, and generation to generation. Individuals, groups, organizations and nations sought to build on this. Knowledge became the basis for creating technological products, some good, some destructive and a means of dominance and coercion. As a result, knowledge and technology are the new currencies of power.