AREND SOETEMAN In the past we lived on one earth, but in many different worlds. Different civilisations, in regions far apart, knew about one another (at least from about the 16th century), they competed with one another or tried to dominate the other, they influenced one another, but in many important aspects they were independent from one another. Somewhere in the 20th century, however, this changed. There is no far apart anymore. We have lived through two European wars, which developed into world wars. Modem aeroplanes allow us to travel in only a couple of hours around the world. Instant...