The term “practical utopia” may seem to suffer from an inoperable inner tension. Is it an oxymoron? It could be, but whether it is or is not depends on its meaning. The meaning of “practical” taken from the New Shorter Oxford Dictionary (Brown 1993, 2317) that is most suitable to this volume is “inclined or suited to action”. We live in a period of history that may turn out to be more destructive than the medieval period referred to as “The Black Death”. Between 1346 and 1353 this particular plague has been estimated to have killed as many as two-thirds of the European population. Europeans did try to act practically to contain the Black Death, but their practical actions were largely ineffective because they were not informed by causal knowledge. The Black Death appeared to be passed from person to person, but no one knew that rats were significant movers of the disease.