The Nature of Man – Part One

by Mortimer J. Adler, Ph.D.

“THE NATURE OF MAN” was an appropriate title for the first formal lecture given at the opening of the Aspen Institute for Humanistic Studies. That lecture was given by Mortimer Adler on July 1, 1950. Now, in this interview with Max Weismann, forty-five years later, he sums up his views on aspects of Human Nature, Nurture, Culture, and their relation to Natural Justice and Natural Rights.



Weismann: I would like to begin this discussion by asking you to comment on an extraordinary error that has arisen in this century inhering in the repudiation of human nature made by social scientists and existentialist philosophy.

Adler: This egregious mistake consists in denying that man has a specific nature comparable to the specific natures to be found in the zoological taxonomy in the classification of animals according to their generic and specific natures. As the social scientists put it, the differences among human groups racial, ethnic, or cultural are primary; there is no common human nature in which they all share. As the existentialists put it, man has an existence, but no essence: the essence of each human being is of his or her own making. The French existentialist Merleau-Ponty sums up this error by saying, “It is the nature of man not to have a nature.”

Weismann: Before you explicate the full character of this mistake, what is its most serious consequence?

Adler: If moral philosophy is to have a sound factual basis, it is to be found in the facts about human nature and nowhere else. Nothing else but the sameness of human nature at all times and places, from the beginning of Homo sapiens, can provide the basis for a set of moral values that should be universally accepted. Nothing else will correct the mistaken notion that we should readily accept a pluralism of moral values as we pass from one human group to another or within the same human group. If the basis in human nature for a universal ethic is denied, the only other alternative lies in the extreme rationalism of Immanuel Kant, which proceeds without any consideration of the facts of human life and with no concern for the variety of cases to which moral prescriptions must be applied in a manner that is flexible rather than rigorous and dogmatic.

Now to the explanation of the mistaken denial of human nature, which while conceding that all human beings have certain common anatomical and physiological traits number of bones, number of teeth, blood type, number of chromosomes, the period of parturition, and so on–denies their psychological sameness–the sameness of the human mind and its behavioral tendencies.

Consider other animal species. If you were to investigate any one of them as carefully as possible, you would find that the members of the same species, living in their natural habitats, manifest a remarkable degree of similarity in behavior. You might find differences in size, weight, shape, or coloration among the individuals you examined. You might find behavioral deviations here and there from what would have become evident as the normal behavior of that species. But, by and large, you would be impressed by the similitudes that reigned in the populations you examined. The dominant likeness of all members of the species would lead you to dismiss as relatively insignificant the differences you found, most of which can be explained as the result of slightly different environmental conditions. That dominant likeness would constitute the nature of the species in question.

Now lets consider the human species. Its members inhabit all the regions of the globe, under the most widely divergent environmental conditions. Let us suppose you were to visit all the human populations wherever they existed. Let us suppose the visit not be a casual one, but one in which you lived for a time with each of these populations and studied them closely. You would come away with the very opposite impression from the one you took away from your investigation of the populations from the other animal species. You were there impressed by the overwhelming similitude that reigned among its members. Here, however, you would find that the behavioral differences were dominant rather than the similarities.

Weismann: But as human beings we are also animals; therefore, don’t we share many of the same traits?

Adler: Of course human beings, like other animals, must eat, drink, and sleep. We all have certain biological traits in common and there can be no doubt we share the nature of other animals. But when you come to their distinctive behavioral traits, how different one human population will be from another. They will not only differ in the languages they speak, you will have some difficulty in making an accurate count of the vast number of different languages you will have found. They will differ in their dress, in their adornments, in their cuisines, in their customs and manners, in the organization of their families, in the institutions of their societies, in their beliefs, in their standards of conduct, in the turn of their minds, in almost everything that enters into the ways of life they lead. These differences will be so multitudinous and variegated that you might, unless cautioned against doing so, tend to be persuaded that they were not all members of the same species.

Weismann: This view seems preposterous to a person of common sense, how did it come about?

Adler: Consider, the behavioral differences between one human race and another, between one racial variety and another, between one ethnic group and another, between one nation and another, these differences would seem to be dominant. It is this that might lead you to conclude that there is no human nature in the sense in which a certain constant nature can be attributed to other species of animals. Even if you did not reach that conclusion yourself, you might understand how that conclusion is plausible. Furthermore, unlike most other species of animals, the members of the human species appear to have formed subgroups that differentiated themselves, one from another. Each subgroup has a distinctive character. The differences that separate one subgroup from another are so numerous and so profound that they defy you to say what remains, if anything, that might be regarded as a human nature common to all.

Weismann: What then is the basis for the denial of human nature?

Adler: The denial of human nature rests ultimately on the striking contrast between the dominant behavioral similitude that prevails among the other animal species and the dominant behavioral differentiation that prevails among the subgroups of the human species. Looked at one way, the denial of human nature is correct. The members of the human species do not have a specific or common nature in the same sense that the members of other animal species do. This, by the way, is one of the most remarkable differences between man and other animals, one that tends to corroborate the conclusion that man differs from other animals in kind, not in degree. But to concede that the members of the human species do not have a specific or common nature in the same sense that the members of other animal species do is not to admit that they have no specific nature whatsoever.

Weismann: How then would you state what alternative is left open for a resolution of this issue?

Adler: The answer can be simply stated: The members of the human species all have the same nature in a quite different sense.

Weismann: In what sense then is there a human nature, a specific nature that is common to all human beings?

Adler: It can be given in a single word: “potentialities.” Human nature is constituted by all the potentialities that are species-specific properties common to all members of the human species. It is the essence of a potentiality to be capable of a wide variety of different actualizations.

Weismann: Would you give us an example of a common human potentiality that is not shared by other animals?

Adler: Consider for a moment, the human potentiality for syntactical speech that is actualized in thousands of different human languages. Having that potentiality, a human infant placed at birth in one or another human subgroup, each with its own language, would learn to speak that language. The differences among all human languages are superficial as compared with the potential for learning and speaking any language that is present in all human infants at birth.

Weismann: Does what you just said about one human potentiality apply to all the other common potentialities of human beings?

Adler: Yes, each underlies all the differences that arise among human subgroups as a result of the many different ways in which the same potentiality can be actualized. To recognize this is tantamount to acknowledging the superficiality of the differences that separate one human subgroup from another, as compared with the samenesses that unite all human beings as members of the same species and as having the same specific nature. In other species of animals, the samenesses that constitute their common nature are not potentialities but rather quite determinate characteristics, behavioral as well as anatomical and physiological. This accounts for the impression from studying these other species–the impression of a dominant similitude among its members.

Weismann: How do you account for the opposite impression of dominant differences among human subgroups?

Adler: The explanation of it lies in the fact that, as far as behavioral characteristics are concerned, the common nature that all the subgroups share consists entirely of species-specific potentialities. These are actualized by these subgroups in all the different ways that we find when we make a global study of mankind.

Weismann: What, then, is the precise mistake made by the cultural anthropologists, the sociologists, and the other behavioral scientists when they deny the existence of human nature?

Adler: It is in their failure to understand that the specific nature in the case of the human species is radically different from the specific nature in the case of other animal species.

Weismann: Having established the sameness of the human species which consists in its common human potentialities, psychological and behavioral, in addition to its common anatomical and physiological traits, what are some of the main differences in kind between the human species and other animal species?

Adler: I have dealt with this subject in great detail in a book I wrote in 1967, “The Difference of Man and the Difference It Makes,” and in another book in 1990, “Intellect: Mind Over Matter.” So, here I will only state the most important and obvious ones: Intellect is a unique human possession. Only human beings have intellects. Other animals may have sensitive minds and perceptual intelligence, but they do not have intellects.

No one is given to saying that dogs and cats, horses, pigs, dolphins, and chimpanzees lead intellectual lives; nor do we say of nonhuman animals that they are anti-intellectual, as some human beings certainly are. Other animals have intelligence in varying degrees, but they do not have intellectual powers in the least degree.

Free will or free choice, which consists in always being able to choose otherwise, no matter how one chooses, is an intellectual property, lacked by nonintellectual animals. Some of their behavior may be learned and thus acquired rather than innate and instinctive, however it is determined by instinct or by learning, it is determined rather than voluntary and freely willed.

A person is a living being with intellect and free will. That is both the jurisprudential and the theological definition of a person. Everything else, animate or inanimate, totally lacking intellect and free will, is not a person but a thing. Only persons have natural and unalienable rights. These we call human rights. There is no comparable animal rights.

Weismann: What are some of the ordinary behavioral differences exclusive to human beings?

Adler: Other animals live entirely in the present. Only human individuals are time-binders, connecting the present with the remembered past and with the imaginable future. Only man is a historical animal with a historical tradition and a historical development. Human life changes from one generation to another with the transmission of cultural novelties and with accretion of accumulated cultural changes and institutional innovations. Nothing like these innovations and changes can be found in any other species.

Only man makes machines, for the purpose of making products that cannot be produced in any other way. The kind of thought that is involved in designing and building a machine betokens the presence of an intellect in a way that the use of hand tools does not.

Only man makes works of art that we regard as fine rather than useful because they are made for the pleasure or enjoyment they afford. The songs made by a given species of bird remain the same for all members of that species generation after generation. In contrast, in the making of drawings or paintings, from the sketches drawn on the walls of Cro-Magnon caves down to the present day, the extraordinary variety in human works of art shows that human artistry is not instinctive, and therefore not the same for all members of the species from one generation to the other.

Weismann: It seems to me that all the differences in kind so far mentioned cannot be explained except by reference to man’s exclusive possession of an intellect with its power of conceptual thought and its power of free choice. But suppose I am not yet persuaded, what other distinctive, unique human performances can you elucidate?

Adler: Only human beings use their minds to become artists, scientists, historians, philosophers, priests, teachers, lawyers, physicians, engineers, accountants, inventors, bankers, statesmen. Only among human beings is there a distinction between those who behave ethically and those who are knaves, scoundrels, villains, criminals. Only among human beings is there any distinction between those who have mental health and those who suffer mental disease or have mental disabilities of one sort or another.

Only in the sphere of human life are their such institutions as schools, libraries, hospitals, churches, temples, factories, theaters, museums, prisons, cemeteries, and so on. I hope you are now persuaded that human and nonhumans differ in kind, not merely in degree.

Weismann: One still may ask, what of it? What does it all really mean? How is this crucial to our understanding of our lives and our world?

Adler: I have already answered your questions in part by calling your attention to the meaning of human personality–that only humans are persons, not things, and have the dignity and worth that belongs only to persons, the rights that belong only to persons, and the moral obligations that belong only to persons. There is, in addition, one further consequence that I have not yet mentioned.

The Declaration of Independence asserts that all human beings are, by nature, equal, and they are equally endowed with the same natural or unalienable rights. All of us know, as a matter of fact, that any two individuals that we may compare with one another will be unequal in a large variety of respects. This leads to how we understand the equality that all humans possess all, with no exception whatsoever and to how we understand their myriad individual inequalities?

Weismann: Before you go on, tell me the basic definition or meaning of the terms equality and inequality?

Adler: Most persons, I have found, do not know the answer to this question, yet it is both short and simple. Two things are equal in a given respect, if in that respect, one is neither more nor less than the other. Two things are unequal in a given respect if in that respect, one is more and the other less than the other.

Weismann: Am I correct in understanding that you are saying there is only one respect in which all human beings, all without any exception, are equal?

Adler: Precisely, one human being is neither more nor less human than another. They all have the same species-specific common properties–the innate potentialities that constitute their human nature.

Weismann: But individual human beings do differ from one another in the degree to which they possess these common human properties, and with respect to such differences, can they be both equal and unequal?

Adler: Yes. These individual differences in degree may be due either to their different innate endowments or to their different individual attainments. Thus understood, there is no incompatibility between the statement that all human beings are equal in only one respect and the statement that they are also unequal in many other respects.

Weismann: Before we go on to the next topic, I have two further questions that relate to humans beings as social animals, how do they differ from some other animal species that have natural associations, and to what consequence?

Adler: You are quite correct in pointing out that humans and some other nonhuman animals are gregarious and are naturally impelled to associate with one another. But while man is not the only social animal, humans are the only political animals. Because they have intellects and free will, they voluntarily constitute the societies in which they live–their domestic, tribal, and political associations. All animal societies or groupings are instinctively determined, and thus they are all purely natural societies, differing from species to species but everywhere the same in the same species. Only human societies are both natural and conventional, natural by natural need, not by instinctive determination. Motivated by natural need, they are conventionally instituted by reason and free will; and so, within the same species, they differ at different times and places.

As to the consequence, let me say that, quite apart from the doctrines that prevail among mankind, the ultimate resolution of the question about how man differs from other things will make a difference–to the future course of human affairs; for the image we hold of man cannot fail to affect the attitudes that influence our behavior in the world of action, and the beliefs that determine our commitments in the world of thought.

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