What Makes Us Human?

Given the discussion last week about Adam, Noah, and the early hominids, I’d like to rerun this previous post from the book: Minds, Brains, Souls, and Gods: A Conversation of Faith, Psychology and Neuroscience by Malcolm Jeeves.   It covered Chapters 9-12 in the book, the chapters being: Chapter 9: What Makes Us Human? The Development of Evolutionary Psychology, Chapter 10: Are Humans Different? What About Morality in Animals, Chapter 11: What is the Difference Between Altruism, Altruistic Love, and Agape?, and Chapter 12: Does Language Uniquely Define Us as Humans?

I’ve lumped chapters 9-12 together because, in them, Jeeves is exploring the question; what makes us unique from other animals?  I think that is a worthwhile question to discuss.

Jeeves begins by noting that the question has a long history of being raised.  He quotes from a review of Frans de Waal’s book “Good Natured: The Origins of Right and Wrong in Humans and Other Animals” (and notes he is a leader in the field):

From the beginning philosophers have agonized over the question of what makes us humans.  Is the difference in kind or merely a difference in degree between ourselves and other animals?”

I think that puts the question in its basic essence: difference in kind or merely in degree?  Blaise Pascal wrote in 1659:

It is dangerous to show a man too clearly how much he resembles the beast, without at the same time showing him his greatness.  It is also dangerous to allow him too clear a vision of his greatness without his baseness.  It is even more dangerous to leave him in ignorance of both.

The discussion among Imonk commenters last time pretty well concluded that the difference between humans and other animals isn’t the presence of some immaterial soul magically implanted by God.  In fact the demonstration from the Bible itself (as exegeted by professor of Old Testament at Asbury seminary, Lawson Stone) shows we are “souls” that is “living beings” as are at least the higher, more sentient animals.

The main issue in this chapter, for Malcolm’s student, is the evolutionary basis of evolutionary psychology.  If you believe that God’s mechanism of bringing humans into existence was a special, instantaneous, creation event, then you are going to view evolutionary psychology as presuppositional atheistic materialism.  If you believe that evolution was God’s mechanism for creation then “out of the dust of the ground” becomes the metaphor for God forming us through a process of development from non-living matter to living simple organisms to living complex organisms to living complex organisms that recognize and relate to him.

So what characteristics of the mind are uniquely human?  Jeeves cites research on “mind reading” or the ability of an animal to understand the mind of another animal.  Jeeves cites the work of Michael Tomasello who published a study in 2010 where he gave a comprehensive battery of cognitive tests to three groups: a large number of chimpanzees, a group of orangutans and a large group of two and half year old children.  The test battery apparently consisted of a whole lot of different nonverbal tasks designed to assess cognitive skills, involving physical and social problems.  Tomasello and his colleagues found that, as reported in the past, the children and the apes show similar skills when dealing with the physical world, but already by age 2 1/2 the children had more sophisticated cognitive skills than either of the ape species studied when it came to dealing with the social world.  “Distinct species-unique skills” of what the researchers called social cognition had emerged in the children by age two and a half.

The next chapter deals with the question of morality in animals.  Jeeves first discusses recent research that show the existence of “cultures” in animals.  He notes a study by Frans de Waal that showed tool use in a subset of chimpanzees that seemed to be passed on by culture and tradition, and another study from McMaster University in 2010 that showed similar social learning in mongooses, animals not normally regarded as close to us from an evolutionary point of view.

Jeeves then quotes Francisco Ayala, leading American evolutionary biologist, who believes the clue to understanding how humans differ from non-human primates is to be found in the difference between what Ayala and fellow evolutionary biologists call adaptations and exaptations.  Ayala (“The Difference of Being Human: Morality”, Proceeding of the National Academy of Sciences 107, May 11, 2010: 9015-22) says:

Evolutionary biologists define exaptations as features of organisms that evolved because they served some function but are later co-opted to serve an additional or different function, which was not originally the target of natural selection.  The new function may replace the older function or co-exist together with it.  Feathers seem to have evolved first for conserving temperature, but were later co-opted in birds for flying… The issue at hand is whether moral behavior was directly promoted by natural selection or rather it is simply a consequence of our exalted intelligence, which was the target of natural selection (because it made possible the construction of better tools).  Art, literature, religion, and many human cultural activities might also be seen as exaptations that came about as consequences of the evolution of high intelligence…

The capacity for ethics is an outcome of gradual evolution, but it is an attribute that only exists when the underlying attributes (i.e. the intellectual capacities) reach an advance degree.  The necessary conditions for ethical behavior only come about after the crossing of an evolutionary threshold.  The approach is gradual, but the conditions only appear when the degree of intelligence is reached such that the formation of abstract concepts and the anticipation of the future are possible, even though we may not be able to determine when the threshold was crossed.

What Ayala is saying is what I was trying to get across with my analogy of water flow going from subcritical to supercritical.  Not everything in nature is a gradual continuum or spectrum.  Sometimes there are “nick points” when a certain threshold is reached and a jump is made to a wholly different level from what existed before.  After all, whoever went to Africa to study a group of nonhuman primates and found they had hospitals, libraries, technology parks, art galleries, churches, symphony orchestras and so on and so on?  It seems to me that it has become too easy to gloss over these enormous and fundamental differences, but the question is why, with such similar brains, are we so comprehensively different?

In Chapter 11, Jeeves discusses altruistic behavior in humans and animals.  Evolutionary theory attempts to answer the question of self-sacrificial behavior by arguing that genes favoring altruism can spread in future generations if their costs to the altruist’s personal reproductive success is outweighed by the benefits in reproductive success of altruists’ relative carrying copies of the same genes – what is called “kin selection”.  Second, it proposes that genes favoring altruism could spread if the altruism is sufficiently reciprocated, what is called “reciprocal altruism”.  One of the most graphic examples of the first is honey-pot worker ants, who do nothing but hang from the ceiling of their ant colony, acting as receptacles or storage jars for honey, which some workers fill them with and which the colony draws on when needed.  At an individual level, that is self-sacrifice.  Examples of reciprocal altruism appear to be much rarer.  The classic example is vampire bats, who are in real danger of starving if they do not get their blood meal on a particular evening.  If this happens they are fed back in their colony by an unrelated nest mate, to whom they are likely to repay the favor on another night.

These two examples necessitate a warning: we must not assume that because two behaviors are similar, the mechanisms underlying them are necessary similar or identical.  Jeeves notes that leading evolutionary psychologist Frans de Waal has written helpfully about how to understand altruistic behaviors, as well as other kinds of behaviors, that traditionally have been regarded as showing evidence of some sort of moral sense in an individual or group.  In his book, Good Natured, de Waal warns against unthinking reductionism.  He cautions:

Even if animals other than ourselves act in ways tantamount to moral behavior, their behavior does not necessarily rest on deliberations of the kind we engage in.  It is hard to believe that animals weigh their own interests against the rights of others, that they develop a vision of the greater good of society, or that they feel lifelong guilt about something they should not have done.”  And he goes on, “To communicate intentions and feelings is one thing; to clarify what is right, and why, and what is wrong, and why, is quite something else.  Animals are no moral philosophers.”  Of the moral sense he later writes, “The fact that the human moral sense goes so far back in evolutionary history that other species show signs of it plants morality firmly near the center of our much-maligned nature.”

De Waal gives a good summary of the issue, I think, and it points again to the “nick point” nature of the evolutionary transition from non-human to human.

In the next Chapter 12: Does Language Uniquely Define Us As Humans, Jeeves take a similar tact in the discussion.  He notes the abundant research that shows all types of rudimentary language use in animals from the bee waggle dance to the learning of sign language in the great apes. But then he quotes from a 2006 report of a working group of the Academy of Medical Sciences in Britain, “The Use of Nonhuman Primates in research.”

The outstanding intelligence of humans appears to result from a combination and enhancement of properties found in non-human primates, such as theory of the mind, imitation, and language, rather than from unique properties.

So what about love, and in particular, agape love?  Jeeves notes:  Altruism is what we might call having regard for the actions or motivations of others.  Altruistic love normally adds an additional feature, a deep affirmative affect, to altruism.  And agape is altruistic love extended to all humanity.  But in addition to that, it has a very special use in the hands of the New Testament writers.  There agape is the Greek word used to describe a form of unlimited altruistic love seen supremely in the self-giving love of Christ on the cross (and in rough equivalents in Judaism, Buddhism and other great religious traditions).  Jeeves concludes:

My own view is that from a Christian perspective there are no grounds for believing that we are all created identical in terms of things like personality.  Indeed, the apostle Paul makes it clear that we are in fact all very different and we have many different gifts.  I was reminded recently when reading some of the things that the apostle Paul had to say to Christians at Corinth about the way that some of them were boasting about themselves and their behavior.  Paul said that by the standards of the world, the Corinthians may have had something of which to boast, but that Christians do not accept the standards of the world.  Christians acknowledge that in themselves they are nothing.  They owe everything to the grace of God and there is no place for boasting about one’s achievements.  As Christians we acknowledge that we are all different, and it is the grace of God that enable us, in the context of the individual differences, to show agape love as much as we are able.