Throughout history Philosophers have argued that human beings are different from other animals and therefore that they have a distinctive human nature. They have differed over what is distinctive about human nature of course, but few have argued that there is nothing distinctive.  Theologians also agree that there is a distinctive human nature, given by God and referred to in terms of the soul, which humans have, and animals do not.  Nevertheless, as Darwin’s theory of evolution through natural selection was widely accepted, some philosophers started to question the old assumption that human beings are ontologically different from animals.  For example, while philosophers from Plato to Kant had focused on reason as the distinctive characteristic of human nature, biological research started to show that some animals have a higher degree of intelligence than some human beings.  Further, awareness of the diversity within the human species and the role that nurture has on forming our natures also cast doubt on the existence of a single human nature that all people share.  As a result, by the 20^th Century, both Sigmund Freud and existentialist Jean Paul Sartre argued that there is no essential, shared and distinctive human nature. Despite this, there is a distinctive human nature, although it is fair to say that not everyone fully exemplifies this.

Firstly, even though not all people are rational, it is difficult to suggest that any other animal has even a tiny part of the rational capabilities of even the average human being.  Our brains are structurally different from even the highest of the primates, with far larger areas devoted to language and communication as well as abstract thought. As Plato first observed, human beings have a distinctive tripartite soul, being rational as well as spirited and appetitive. Aristotle agreed, pointing out that humans may share the nutritive and sensitive aspects of their soul with animals, but not their rational soul, which is distinctive to humans. Much later, Descartes and Kant agreed that it is rational thought that distinguishes human beings from animals.  As Kant pointed out, reason is what facilitates freedom and moral status, neither of which animals have either. These arguments are convincing because they account for the essential difference between human and animal existence.  Although it is fair to say that not everybody with human DNA is fully rational, free or morally capable, most people are.  In the same way as it is fair to say that there is such a thing as an oak tree, distinct from being a beech tree or a sunflower even though some oak trees die as saplings or are genetically different from others, so it is fair to say that there is a distinctive human nature despite the fact that some people don’t fully exemplify this.

Secondly, from a theological point of view, human beings have a distinctive human nature because God created human beings and not animals “In His own image.” Genesis 1:26. Further, in Genesis 2 god breathed a soul into the human form he had made from the dust of the ground “making the man [Adam] a living being.” The Bible is clear that animals did not so receive a soul from God, and although the Bible is also silent about God breathing a soul into women in Genesis 2 – women being taken out of man instead – Genesis 1 confirms that both men and women were created in God’s image, suggesting that both sexes share in a single distinctive human nature and are equally connected to God. St Augustine drew on Genesis to develop his theory of human nature, arguing that humans are all capable of living in a state of caritas with God, as God originally and distinctively created us before the Fall, but that because of the Fall we are sinful by nature and afflicted by lust, trapped by Original Sin for which we cannot ourselves atone, so that we do what we know that we ought not to do and cannot do what we know that we ought to do [Romans 7].  This means that human beings share the distinctive condition of knowing what is right and good, but being unable to do what we know that we ought, except by God’s grace. Kant broadly agreed with St Augustine’s analysis of human nature, pointing out how even disregarding the story of the Fall, individually we inevitably fall prey to Radical Evil which makes it impossible to do what we know we ought without being morally regenerated, which there is no rational basis for hoping is possible. This suggests that another element of our distinctive human nature is to have faith and to keep hoping and trying when there is no good reason to do so. Today the vision of what makes us human developed by St Augustine and later refined by Kant remains highly influential, even amongst people who are not religious. Despite being pessimistic, many psychologists find that human nature is distinctive because it is contradictory and flawed. This shows that there is a distinctive, if flawed, human nature that rings true for both believers and non-believers, speaking to their experiences of being human.

Nevertheless, it is clear that rationality as well as freedom and moral capacity are not qualities shared by everybody who has human DNA. DNA is varied, but the degrees to which people are capable of autonomous rational thought and moral agency is even more so. Few children in particular seem to share in what philosophers claim is our distinctive human nature, and clearly children are human!  Perhaps rationality and moral agency are markers not of what makes us human, but of what some humans are capable of. This point is not convincing though, because the fact that acorns don’t have leaves is not evidence that there is no distinctive oak-nature!  Just because some humans don’t fully exemplify our distinctive human nature does not mean that such a nature does not exist. Indeed, Kant saw the inevitability of making irrational decisions during childhood as the root-cause of the Radical Evil that is such a part of what makes human nature distinctive. As children we can’t act autonomously, doing our rational duty for its own sake, meaning that we develop bad habits of acting out of fear or habit or deference to authority.  These habits, along with the knowledge that because of them we don’t deserve any heavenly reward which would provide the reward we need to keep doing what is right, make it impossible to act as a “Good Will” even though we still feel the demand of the moral law as a categorical imperative.  This shows that the fact that human beings are diverse and that many people don’t fully exemplify our distinctive human nature does not mean one does not exist.

In addition, atheists might criticise the idea that there is a distinctive human nature because human beings are born as “blank slates”, so that what some people claim is nature is actually nurture.  Locke, Hobbes and more recently Freud and BF Skinner all explain the diversity between people by denying the existence of anything significant in terms of “human nature”.  Nevertheless, even if people do learn a lot of what is assumed to be natural, there are fundamental human characteristics which are natural and distinctive to humans. There are qualities and capabilities associated with having Human DNA; no person can learn to fly, however they are brought up!  Also, as Chomsky has argued, there are capabilities hard-wired into the brain, such as language-acquisition, so why not other capabilities also.  This would explain why most people have a similar sense of morality, as CS Lewis pointed out. Other atheists might argue that there is no distinctive human nature because human beings evolved from common ancestors with apes… meaning that there is no static or fixed human nature and that in the past there would have been less and eventually no distinction between humans and apes at all.  Richard Dawkins accepts this view, criticising the traditional philosophical and the religious view of human nature and arguing that we are “lumbering robot vehicles for our genes” and that we are “survival machines” just as all animals are. Existentialist philosopher Jean Paul Sartre developed this line of argument, suggesting that “there is no human nature because there is no God to conceive it.” The idea of the human as distinct from the ape, or the oak as distinct from the beech is a product of the human mind and its desire to conceptualise and understand the world and not descriptive of objective reality. However, this argument is no more convincing as even if our distinctive human nature has evolved and will evolve more in the future, there is no doubt that there is something that makes a person a person today, even if that is an idea or ideal within our conceptual framework.  Nobody could really expect that the “distinctive human nature” could be an object that could be studied independently of the humans who exemplify it in any case. As Aristotle pointed out, there is still a soul even though it is not separable from the body, just as there is still a seal-shape even though it can’t be separated from wax. Even Dawkins admits that the word “soul” has a Soul 1 meaning as a way of referring to personality, creativity etc. This suggests that there is still a distinctive human nature even if it is an idea that can’t be separated from the people who exemplify it and even if not every person exemplifies it fully.

In conclusion, there is a distinctive human nature even though not everybody fully exemplifies it, even if we don’t clearly know what it is and even though it has probably evolved and will continue to evolve. Human nature may not be fixed or a thing we can study independently of the people who exemplify it, but it is as real as any other part of our conceptual framework.