Of the 3,000 simple societies so far examined by anthropologists, all appear to have laws of exogamy and endogamy. Marriage is forbidden within a restricted family circle, but also ouside the cultural group, the object being to avoid cultural hybridization and hence the production of sub-systems that are differentiated parts neither of one system nor of another. What is today regarded as prejudice against people of different ethnic groups is a normal and necessary feature of human cultural behaviour, and is absent only among members of a cultural system already far along the road to disintegration. The notion of the universal brotherhood of man is therefore totally incompatible with the systemic approach to human cultural systems. It is as absurd as the notion that the cells, making up a vast number of different biological organisms, can be shuffled and still give rise to viable biological systems.
Industrial countries tend to develop labour shortages and to import labour from elsewhere.
In this way quite large ethnic minorities are being built up in many countries. In addition, economic development is tending towards the development of ever-larger political units, which often embrace ethnic groups with little in common with each other. All this is creating a very unstable situation, one which can only lead to civil wars and to the massacre of minorities singled out as scapegoats when inevitable economic and social crises occur. Except for apartheid, Goldsmith also considers forced migration a solution. The nationalists in former Yugoslavia have already started this grand project.