Human Nature and Nurture
The French existentialist Merleau-Ponty summarizes the main point of nihilistic existentialism is the statement that "it is the nature of man not to have a nature." This denial of human nature, the same for all members of the human species, is so crucial to moral and political philosophy that we must point out the error made by the existentialist and also by a great many social scientists who also confuse the nurture with nature.
Those who make this error would readily concede that in animals other than man, the individual members of a given taxonomic group do have a specific nature, genetically determined. They recognize that all lions and tigers, all whales and porpoises, behave in the same way.
Their genetically determined modes of behavior, which are the same in all members of a given species, constitute the properties of their specific nature. But it is maintained also that members of the human species do not have genetically determined behavioral dispositions that can be regarded as properties of a specific human nature.
Those who hold this view are quite correct in thinking that genetically determined human nature is different from the genetical determined specific natures of other animals. In a global investigation, one would find that the behavioral dispositions of human beings are as varied as the places where we find human beings in action.
The reason is that specific human nature is constituted only by the possession at birth of the same potentialities for behavior rather than, as in other animals, the same actual behavioral dispositions.
Potentialities are capable of a wide rage of actualization. Take, for example, the capacity that all human beings have for acquiring language, think of the innumerable languages that human beings do, in fact, acquire. An infant whose parents are French, taken at birth and brought up in a Swedish household, will learn to speak Swedish. 'That infant shares with every other infant regardless of biological paternity, the same behavioral potentialities that can be actualized differently when the child is reared in a household that is a different from the family in which it was born. One property of specific human nature is the potentiality for learning to speak a human language. The language that the child learns to speak is determined not by its specific nature, but by the way in which it is nurtured.
It is nurture that determines the different actualization of all the potentialities that constitute specific human nature. As they are nurtured differently at different times and places. But they all have at birth the same behavioral potentialities, and these potentialities constitute that specific nature of the human being.