The Concept of Human Nature

The Concept of Human Nature

The concept of human nature is a common part of everyday thought. The ordinary person feels that he comes to know human nature through the character and conduct of the people he meets. Behind what they do he recognizes qualities that often do not surprise him: he forms expectations as to the sort of qualities possessed by other human beings and about the ways they differ from, for example, dogs or horses.

People are proud, sensitive, eager for recognition or admiration, often ambitious, hopeful or despondent, and selfish or capable of self-sacrifice. They take satisfaction in their achievements, have within them something called a conscience, and are loyal or disloyal. Experience in dealing with and observing people gives rise to a conception of a predictable range of conduct; conduct falling outside the range that is considered not to be worthy of a human is frequently regarded as inhuman or bestial whereas that which is exceptional--in that it lives up to standards which most people recognize but few achieve--is regarded as superhuman or saintly.

The common conception of human nature thus implicitly locates man on a scale of perfection, placing him somewhere above most animals but below saints, prophets, or angels. This idea was embodied in the theme, Hellenic in origin, of the Great Chain of Being--a hierarchical order ascending from the most simple and inert to the most complex and active: mineral, vegetable, animal, man, and finally divine beings superior to man. In the Middle Ages these divine beings constituted the various orders of angels, with God as the single, supremely perfect and omnipotent, ever-active being.

There was a tendency in this theory to take for granted the commonality among all human beings, something by virtue of which they could be classified as fully human, which differentiates them from all other animals, and which gives them their place in the order of things. Yet, as with many notions that are habitually employed, the request for a precise definition of "human nature" proves highly problematic.

The Greeks--most notably Plato and Aristotle--introduced the notion of form, nature, or essence as an explanatory, metaphysical concept. Variations on this concept were central to Western thought until the 17th century. Observation of the natural world raised the question of why creatures reproduced after their kind and could not be interbred at will and of why, for example, acorns grew into oaks and not into roses.

To explain such phenomena it was postulated that the seeds, whether plant or animal, must each already contain within them the form, nature, or essence of the species from which they were derived and into which they would subsequently develop. This pattern of explanation is preserved in the modern biological concept of a genetic code that is embodied in the DNA molecular structure of each cell. There are important differences, however, between the modern concept of a genetic code and the older, Greek-derived concept of form or essence.

First, biologists are now able to locate, isolate, experimentally analyze, and manipulate DNA molecules in what has become known as genetic engineering. Being the structures responsible for physical development, DNA molecules represent the terms by which man can be biologically characterized. Forms or essences, on the other hand, were not observable; if they were granted any independent existence, it was as immaterial entities.

The form, nature, or essence of man or of any other kind of being was posited as a principle present in the thing, determining its kind by producing in it an innate tendency to strive to develop into a perfect example of itself--to fulfill its nature and to realize its full potential as a thing of a given kind. This gave rise to a teleological, or purposive, view of the natural world in which developments were explained by reference to the goal toward which each natural thing, by its nature, strives; i.e., by reference to the ideal form it seeks to realize. By contrast, the genetic structure present in each cell is now invoked to explain the subsequent development of an organism in a "mechanistic" and nonpurposive way, in which development is shown to be dependent upon and determined by preexisting structures and conditions.

Second, genetic mutability forms an essential part of modern evolutionary biology. Not only are there genetic differences between individuals of a given species to account for differences between them in features, such as coloration, but random genetic mutation in the presence of changing environmental conditions may result in alterations to the genetic constitution of the species as a whole. Thus, in evolutionary biological theory species are not stable; natural kinds do not have the fixed, immutable forms or essences characteristic of biology before the advent of evolutionary theory.

Within either framework, if human nature is understood simply as man's special form of that which is biologically inherited in all species, there remains the delicate problem of discovering, in any given case, exactly what role environment plays in determining the actual characteristics of mature members of the species. Even in the case of purely physiological characteristics this may be far from straightforward: for example, the extent to which diet, exercise, and conditions of work determine such things as susceptibility to heart disease and cancer remains the subject of intensive scientific investigation.

In the case of behavioral and psychological characteristics, such as intelligence, the problems are multiplied to the point where they are no longer problems that can be answered by purely empirical investigation. There is room for much conceptual debate about what is meant by intelligence and over what tests, if any, can be supposed to yield a direct measure of this capacity, and thus provide evidence that an individual's level of intelligence is determined at birth (by nature) rather than by subsequent exposure to the environment (nurture) that conditions the development of all his capacities.

This debate--whether the variation in intelligence levels is a product of the conditions into which people all having the same initial potential are born, or whether it is a reflection of variations in the capacities with which they are born--is very closely related to the question of whether there is such a thing as human nature common to all human beings, or whether there are intrinsic differences among those whom we recognize as belonging to the biological species Homo sapiens.

This is because, as the name Homo sapiens suggests, man is traditionally thought to be distinguished from and privileged above other animals by virtue of his possession of reason, or intellect. When the intellect is positively valued as that which is distinctively human and which confers superiority on man, the thought that different races of people differ by nature in their intellectual capacities has been used as a justification for a variety of racist attitudes and policies.

Those of another race, of supposedly lesser intellectual development, are classified as less than fully human and therefore as needing to be accorded less than full human rights. Similarly, the thought that women are by nature intellectually inferior to men has been used as a justification for their domination by men, for refusing them education, and even for according them the legal status of property owned by men. On the other hand, if differences in adult intellectual capacity are regarded as a product of the circumstances in which potentially similar people are brought up, the attitude is to consider all as equally human but some as having been more privileged when growing up than others.

More radically, the evidence for variations in intelligence levels may be questioned by challenging the objectivity of the standards relative to which these levels are assessed. It may be argued that conceptions of what constitutes a rational or intelligent response to a situation or to a problem are themselves culturally conditioned, a product of the way in which the members of the group devising the tests and making the judgments have themselves been taught to think. Such an argument has the effect of undermining claims by any one human group to intellectual superiority over others, whether these others be their contemporaries or their own forebears. Hence, they may also be used to discredit any idea of a progressive development of human intellectual capacities.

These debates about intelligence and rationality provide an example of the complexity of the impact of evolutionary biology on conceptions of human nature, for the dominant traditions in Western thought about human nature have tended to concentrate attention more on what distinguishes man from other animals than on the strictly biological constitution that he largely shares with them. Possession of reason or intellect is far from being the only candidate considered for such a distinguishing characteristic.

Man has been characterized as essentially a tool user, or fabricator (Homo faber), as essentially social, as essentially a language user, and so on. These represent differing views concerning the fundamental feature that gives rise to all the other qualities regarded as distinctively human and which serve to mark man off from other animals. These characteristics all center on mental, intellectual, psychological--i.e., nonphysiological -- characteristics and thus leave scope for debate about the relation between mind and body. So long as this question remains open, and so long as mental or intellectual constitution remains the central consideration in discussions of human nature, the question of changes in -- and of the possible evolution of -- human nature will remain relatively independent of those devoted to physiological change and hence of strictly biological evolution.

Until the 15th century the standard assumption was that man had a fixed nature, one that determined both his place in the universe and his destiny. The Renaissance humanists, however, proclaimed that what distinguishes man from all other creatures is that he has no nature. This was a way of asserting that man's actions are not bound by laws of nature in the way that those of other creatures are. Man is capable of taking responsibility for his own actions because he has the freedom to exercise his will. This view received two subsequent interpretations.

First, the human character is indefinitely plastic; each individual is given determinate form by the environment in which he is born, brought up, and lives. In this case, changes or developments in human beings will be regarded as the product of social or cultural changes, changes that themselves are often more rapid than biological evolution.

It is thus to disciplines such as history, politics, and sociology, rather than to biology, that one should look for an understanding of these processes. But if disciplines such as these must constitute the primary study of man, then the question of the extent to which this can be a strictly scientific study arises. The methods of history are not, and cannot be, those of the natural sciences. And the legitimacy of the claims of the so-called social or human sciences to genuine scientific status has frequently been called into question and remains a focus for debate.

Second, each individual is autonomous and must "make" himself. Assertion of the autonomy of man involves rejection of the possibility of discovering laws of human behaviour or of the course of history, for freedom is precisely not being bound by law, by nature. In this case, the study of man can never be parallel to the natural sciences with their theoretical structures based on the discovery of laws of nature.