This means that incompetent societies have to be allowed to go to the wall. This is something we in advanced societies do not at present face up to and the reason for this, according to Cattell, is that we have become too soft-hearted. For instance, the foreign aid which we give to the under-developed world is a mistake, akin to keeping going incompetent species like the dinosaurs which are not fit for the competitive struggle for existence. What is called for here is not genocide, the killing off of the populations of incompetent cultures. After all, ninety-eight per cent of the of the species known to zoologists are extinct.
Evolutionary progress means the extinction of the less competent.
To think otherwise is mere sentimentality. As a general rule it would be best for national cultures to keep themselves to themselves and not to admit immigrants. There are several reasons for this. Isolation would give rise to societies with greater diversity and individuality, both culturally and genetically. Indeed, it would be desirable if the human race could evolve several different non-interbreeding species, since this would increase the options for evolution to work on.