The Aristotelian Biology of Thomistic Natural Law (2)

Eric Johnston's dissertation is a valuable study of how Aristotelian biology supports Thomas Aquinas's account of the natural law of marriage. As Johnston indicates, his dissertation is primarily a historical work that tries to understand Aquinas's position, without judging whether that position is defensible as being simply true. But still, it's clear that Johnston is generally supportive of what Aquinas says, and he so he wants to defend Aquinas as making intellectually respectable arguments.

Any defense of Aquinas's biological reasoning today requires some judgment as to whether it is compatible with modern biological science, assuming that we agree that that science is generally correct. And, indeed, Johnston does suggest that Aquinas's biology is roughly compatible on many major points with modern biology, although he does this only briefly and often only in some footnotes.

I would go farther in that direction than Johnston wants to go, and that's why I disagree with him on four points.

First, Johnston assumes that biological science can study only the purely physical side of human life, and therefore it cannot account for the mental or moral reality of human experience (11, 48, 52, 240). But this is not true either for Aristotelian biology or for modern Darwinian biology. Aristotle's biological writings study not just the physical but also the mental capacities of animals, and it's this biological study of animal cognition that is so important for Aquinas. Darwin continued in this tradition in studying the evolution of the mental and moral capacities of animals. Today, the ethology and neuroscience of animal cognition belong to this Aristotelian tradition of biological psychology. It is true that human beings are unique in ways that make them uniquely capable of moral judgment and symbolic reasoning. But even these humanly unique traits can be understood as products of the emergent evolution of primate cognition.

Johnston observes: "modern biology, viewing the animal from a purely physical perspective, cannot engage the question of ensoulment because it does not engage the question of the soul" (240). But while it is certainly true that modern biologists are unlikely to use the language of "soul" and "ensoulment," they will talk about the biology of cognition and mental states. So, for example, as indicated in some recent posts, primatologists will look for evidence that chimpanzees have a "theory of mind."

My second disagreement is that, while Johnston does occasionally defend the Aristotelian biology of sex differences against the charge of sexist bias (27, 158-159, 233-234, 241), I would go farther in this direction in arguing that Aristotle's embryological explanation of male-female differences is close to what we know today from modern biology. Aristotle understood that the formation of a male embryo depended on the action of testicular secretions in the womb, and that in the absence of these secretions, the embryo develops as a female. Consequently, abnormalities of hormonal masculinatization can result in abnormalities of gender identity. I have laid out my reasoning on this in an article: "A Sociobiological Defense of Aristotle's Sexual Politics," International Political Science Review, 15 (1994): 389-415. Some of this same ground is covered by an article cited by Johnston: Michael Nolan, "The Aristotelian Background to Aquinas's Denial that 'Woman is a Defective Male,'" The Thomist, 64 (2000): 21-69.

My third disagreement is that, unlike Johnston, I think that the ecclesiastical persecution of those studying Aristotelian natural philosophy might have made it necessary for Aquinas to engage in esoteric writing to avoid persecution. Dante hints at this in the DIVINE COMEDY (PARADISO, X.82-148). Siger de Brabant was condemned as an Averroist heretic who taught Aristotelian philosophy without regard for Christian faith. Dante puts him in Heaven, and he has Thomas Aquinas praise him as one who "demonstrated truths that earned him envy." Aquinas introduces himself as "a lamb among the holy flock that Dominic leads on the path where one may fatten well if one does not stray off," thus suggesting that Aquinas hid his support for Siger so as not to stray too openly from the faith of the Dominicans.

One place where Johnston might have seen this is in Aquinas's use of embryology to answer the question (in De Potentia, q. 3, a. 9) of whether the rational soul can be transmitted through semen, or whether it must be infused by God's miraculous creation. Johnston notices that this requires an unusually complicated response by Aquinas (241-59). Aquinas indicates that this question of whether natural embryological development can produce the rational soul of a human being "has been answered in various ways by different people" with different "opinions." One of these "opinions" was that yes, indeed, natural reproduction could produce a child with a rational soul. But then the Church condemned such "opinions" and declared that the rational soul must be specially created by God and then infused into the body of the developing child. "Now to maintain that the soul is made by the generation of the body, is to say that it is not subsistent and consequently that it ceases with the body." This is a heresy, and it was one of the propositions condemned by the Bishop of Paris in 1277. Thus, Aquinas could not openly embrace this without being condemned as a heretic (cf. ST, I, q. 118, a. 2). Aquinas argues in defense of the Church's position--that the rational soul must be specially created by God and infused into the body--but he refers to this as an "opinion," which might make a careful reader wonder whether he is fully and honestly affirming its truth.  For Aquinas, "opinion"--as opposed to "science" or "faith"--is affirming something without firm confidence (ST, I-II, q. 67, a. 3).

Aquinas's argument for this "opinion" is that nature is an instrument in the hand of God, and therefore God can intervene at any time to go beyond what the instrument can do on its own. But if God is able and willing to use nature to create nutritive and sensitive souls, as Aquinas says, then why is He not able and willing to use nature to create rational souls? Although a reader might raise this question, Aquinas cannot openly raise it himself without risking persecution.

This is still an issue today with regard to how far the Catholic Church can go in accepting modern evolutionary science. In 1996, Pope John Paul II appeared to endorse the idea of human evolution by purely natural processes. But he also insisted that while evolutionary science can explain the natural evolution of the human body, the appearance of the rational soul unique to human beings requires a miraculous act of God in the embryological process.

My final point of disagreement with Johnston is in his observation: "His account of the natural law is thoroughly theonomic. Natural law is not a way of discerning the good life in abstraction from God" (296). I agree that any orthodox Christian must believe that all of nature, including natural law, is ultimately part of eternal law as created by God. But it does not follow from this that the power of natural law depends on a belief that it is divinely ordained. If that were so, then there would be no reason for Aquinas to distinguish between natural law and divine law, and thus natural law could not be comprehensible as purely natural without supernatural revelation. If natural law corresponds to the natural biological inclinations of the human animal, then why doesn't the natural power of those inclinations hold true for us regardless of our religious beliefs?

To go back to the example of marriage, all human beings should be able to grasp the natural truth that human beings as sexual animals are naturally directed to parental care and spousal love. And while belief in some theological view of marriage might reinforce those natural inclinations, the natural inclinations can stand on their own natural ground even without religious belief. By contrast, the religious view of marriage as a sacrament symbolizing the marriage of Christ and His Church depends upon faith in revelation rather than reasoning about nature.

In addition to my recent posts, some of my older posts on related topics can be found here, here, here, here., and here.

The Aristotelian Biology of Thomistic Natural Law

In some of my recent posts, I have argued that Thomas Aquinas's teaching on natural law is rooted in Aristotle's biology, that this is particularly clear in Aquinas's biological account of the natural law of sex, marriage, and parental care, and that much of this biological reasoning for natural law can be confirmed by modern Darwinian biology.

I must admit, however, that I have not done a thorough study of how Aquinas uses Aristotle's biology in all of his writing. So I was pleased to discover a dissertation that studies how Aquinas uses Aristotle's biology in his account of marriage. Eric M. Johnston wrote a dissertation in 2009 for his Ph.D. in theology at the Catholic University of America, the title of which is "The Role of Aristotelian Biology in Thomas Aquinas's Theology of Marriage." Johnston is now a professor of theology at Seton Hall University. His dissertation is a wonderfully insightful study of all the places in Aquinas's writing where he speaks about marriage, sexuality, and parenthood, and he shows how Aristotle's biological comparisons of human beings and other animals are used by Aquinas to support his understanding of sexual mating and parental care. Johnston's general conclusion is that "Thomas is able to account for all the main Catholic doctrines on marriage through parallels between human and animal procreation" (44).

I agree with Johnston on most of the points he makes. But I disagree on some points.

I agree with the core of Johnston's dissertation, which is to show how Aquinas carefully employed Aristotle's biological writings--especially, The Generation of Animals and The History of Animals--in using animal biology to explain human sexuality, marriage, and parenting. He shows that even when Aquinas does not directly cite Aristotle, Aquinas often uses examples from Aristotle's biological observations.

For example, one of the most important Biblical texts for the Christian doctrines about marriage is the seventh chapter of Paul's First Corinthians. Paul begins this chapter by writing:

Now concerning the matters about which you wrote. It is well for a man not to touch a woman. But because of the temptation to immorality, each man should has his own wife, and each woman her own husband. The husband should give to his wife her conjugal rights, and likewise the wife to her husband. For the wife does not rule over her own body, but the husband does; likewise the husband does not rule over his own body, but the wife does. Do not refuse one another except perhaps by agreement for a season, that you may devote yourselves to prayer; but then come together again, lest Satan tempt you through lack of self-control. I say this by way of concession, not command. I wish that all were as I myself am. But each has his own special gift from God, one of one kind and one of another. To the unmarried and the widows I say that it is well from them to remain single as I do. But if they cannot exercise self-control, they should marry. For it is better to marry than to be aflame with passion. (I Cor 7:1-9)

In Aquinas's Commentary on First Corinthians, one of the remarkable features of his commentary on this passage is that he introduces biological comparisons with other animals (from Aristotle's biological writings), although Paul says nothing about this. Aquinas writes:

Natural reason teaches that man use the act of generation according as it is suitable for generation and education of children. But in brute animals, it is found that in certain species the female alone is not sufficient for the training of the offspring, but the male takes care of the offspring with the female. For this, it is required that the male recognize its offspring. Therefore, in all such animals, as doves, pigeons, and the like, solicitude for the training of offspring is inspired by nature. Wherefore, in such animals, intercourse is not random and indiscriminate, but a definite male is joined to a definite female, not one to another promiscuously, as happens in dogs and such animals, in which the female alone takes care of the offspring. But above all in the human species, the male is required for the education of the offspring, which are attended to not only regarding bodily nourishment, but to a greater degree regarding the nourishment of the soul, as it says in Hebrews (12:9): "We have had earthly fathers to discipline us and we respected them." And consequently, natural reason dictates that in the human species intercourse is not random and uncertain, but is by a definite man to a definite female, who in fact made the arrangement through the law of matrimony.

Thus, therefore, matrimony has three goods. The first is that it is a function of nature in the sense that it is ordered to the production and education of offspring; and this good is the good of offspring. The second good is that it is a remedy for desire, which is restricted to a definite person; and this good is called fidelity, which a man preserves toward his wife, by not going to another woman, and similarly the wife toward the husband. The third good is called the sacrament, inasmuch as it signifies the union of Christ and the Church, as it says in Ephesians (5:32): "This mystery is a profound one, and I am saying that it refers to Christ and the Church."

That comparison of human beings with other sexually reproducing animals states the main principles of Aquinas's teaching on sex, marriage, and familial bonding. Like other animals, human beings are driven by a powerful natural desire for sexual mating. Like other animals whose offspring cannot survive or flourish without parental care, and for whom the care of both parents is often necessary, there is a natural need for long-lasting bonding between the mother and the father for the care of the young. But the parental attachment of the father depends on his confidence that he's caring for his own children rather than the children of another man. This must be so, because love of children is an extension of our self-love, so that we love our children as our own. Even adoption requires some such special attachment so that our adopted children seem to be our own. For human children, parental care includes not just bringing children into existence but also feeding them and educating them, because children need a long period of social learning before they can live as mature young adults.

As thus rooted in human biological nature, human marriage has two natural goods--the good of parental care and the good of spousal love.

For Catholic Christians, there is a third good of marriage that is supernatural--the good of marriage as a sacrament of the Church in symbolizing the supernatural mystery of Christ's marriage to the Church as His bride.

It seems, then, that while the first two goods are matters of natural law as rooted in the biological nature of human beings as sexually reproducing animals, the third good surpasses natural law because to recognize marriage as a sacrament, we need the divinely revealed law of the Bible.

But then we might wonder how far Thomas's Aristotelian biology goes in supporting the Thomistic natural law teaching as grounded in natural experience and reasoning without need for divine revelation. We might also wonder how far modern biological science could support this teaching. On both points, I go farther than Johnston wants to go. I'll explain this in my next post.

Tomasello on the Chimpanzee Theory of Mind and Social Ontology

In an email message responding to my previous post, Michael Tomasello has observed that it's not quite true that his research produces mostly negative findings--stressing what chimps can't do. For example, to the question of whether chimps have a theory of mind, Tomasello's answer is that in many respects they do, while in some respects they don't; and this shows how chimps are both similar to human beings and yet different.

Thus Tomasello's negative conclusions about the limits of chimpanzee cognition are in the service of a positive theory of how human uniqueness evolved.

Some years ago, Tomasello concluded that chimps and other non-human primates have no capacity for understanding the psychological states of other individuals. But more recently, he has decided that new experimental research shows that he was wrong, and that chimps can understand that others perceive and know things and have goals or intentions. For instance, experiments in which chimps are competing for food show that they think about what their competitor can and cannot see, hear, or know. In this sense, chimps do have a theory of mind.

And yet, in another sense, they don't, Tomasello argues, because there is no experimental evidence that chimpanzees understand false beliefs--that other individuals can be not only informed or uninformed but misinformed. By comparison, children as young as 4 years old--and perhaps even younger--do understand that individuals can have false beliefs.

Here's the abstract for one of his articles on this point ("A Nonverbal False Belief Task"):

A nonverbal task of false belief understanding was given to 4- and 5-year-old children (N=28) and to two species of great ape: chimpanzees and orangutans (N=7). The task was embedded in a series of finding games in which an adult (the hider) hid a reward in one of two identical containers, and another adult (the communicator) observed the hiding process and attempted to help the participant by placing a marker on the container that she believed to hold the reward. An initial series of control trials ensured that participants were able to use the marker to locate the reward, follow the reward in both visible and invisible displacements, and ignore the marker when they knew it to be incorrect. In the crucial false belief trials, the communicator watched the hiding process and then left the area, at which time the hider switched the locations of the containers. When the communicator returned, she marked the container at the location where she had seen the reward hidden, when was incorrect. The hider then gave the subject the opportunity to find the sticker. Successful performance required participants to reason as follows: the communicator placed the marker where she saw the reward hidden; the container that was at that location is now at the other location; so the reward is at the other location. Children were also given a verbal false belief task in the context of this same hiding game. The two main results of the study were: (1) children's performance on the verbal and nonverbal false belief tasks were highly correlated (and both fit very closely with age norms from previous studies), and (2) no ape succeeded in the nonverbal false belief task even though they succeeded in all of the control trials indicating mastery of the general task demands.

This research is part of Tomasello's larger research project for understanding the evolutionary psychology of social ontology. As indicated by John Searle and other philosophers, we live in two worlds--a physical reality that is true independently of our subjective awareness and a social reality that depends on our subjective awareness. So, for example, a piece of paper money exists physically as a piece of paper regardless of what we think about it, but its value as money depends on our subjective social agreement. All of our social practices and institutions--money, property rights, government, and so on--are like this. All social animals seem to have some cognitive capacities that allow them to create their social worlds. But human beings seem to be unique in having cognitive capacities that allow them to create social worlds that are far more complex, extensive, and flexible than is the case for other social animals. Any evolutionary science of social cooperation must explain this.

Through his experiments comparing non-human primates and children, Tomasello concludes that while chimps are capable of social coordination, which requires that individuals respond to each other's behavior--as, for example, when chimps engage in group hunting or warfare--they do not show the collaboration through joint intentions based on coordinated plans that arises among young children.

The uniqueness of human institutional ontology is evident in how human beings use language to construct social institutions. But Tomasello thinks that the primary entrance into human social reality is through games of pretend play that display their basic structure among 2-year old children. Through games of pretense, children create social activities through agreement with others on the rules of the game, which shows the crucial step towards human social ontology, a step not taken by chimps. (Of course, to pursue this further, we would have to ask how this is different from the play behavior of other primates.)

REFERENCES
Josep Call and Michael Tomasello, "A Nonverbal False Belief Task: The Performance of Children and Great Apes," Child Development, 70 (March/April 1999): 381-395.

Josep Call and Michael Tomasello, "Does the Chimpanzee Have a Theory of Mind? 30 Years Later," Trends in Cognitive Sciences 12 (2008): 187-192.

Hannes Rakoczy and Michael Tomasello, "The Ontogeny of Social Ontology: Steps to Shared Intentionality and Status Functions," in S. L. Tsohatzidis, ed., Intentional Acts and Institutional Facts: Essays on John Searle's Social Ontology (Dordrecht, The Netherlands: Springer, 2010), 113-137.

More on the de Waal/Tomasello Debate in Primate Research

In my previous post, I briefly surveyed some of the issues in the debate between Frans de Waal and Michael Tomasello in comparing the social intelligence of human beings and other primates--with de Waal stressing the similarities and Tomasello stressing the differences.

I have received a few email messages from folks who think I haven't given enough attention to the flaws in Tomasello's research, which point to at least three major problems.

The first problem is that the results of Tomasello's experiments are mostly negative in emphasizing what chimpanzees and other apes cannot do by contrast with human beings. Such negative results leave us wondering whether this comes from some failing in the methodology that prevented the apes from showing their true abilities. Once people like de Waal try out a new methodology that produces positive results for the apes, it's not clear that Tomasello's research with negative results has much interest.

The second problem is that Tomasello's experiments comparing chimpanzees and human infants are dubious because they are conducted mostly with human experimenters, which creates a disadvantage for the chimps. It is easier for human infants to demonstrate their social skills when dealing with a human experimenter than it is for chimps to do this when dealing with a member of another species. We should expect that the full complexity of chimp social intelligence will be manifested only within chimp groups.

The third problem is that Tomasello's negative results often contradict what researchers are seeing among chimps in the wild. So, for example, de Waal's latest experiments showing chimp prosocial behavior conforms to what researchers like Andrew Whiten and Christophe Boesch have already seen among chimps in the wild in Africa.

The fundamental difficulty running through all of this is that in comparing human beings and other apes, we need to explain both the similarities and the differences.

Tomasello observes:

. . . I am among those who are regularly accused of "raising the bar" on chimpanzees; that is, as soon as we discover that something we thought was a human-chimpanzee difference turns out not to be (e.g., understanding goals), we then posit something else as different and uniquely human (e.g., social imitation, normativity). But this raising of the bar results from the simple fact that there are observable differences between chimpanzee and human societies in terms of such things as complex technologies, social institutions, and symbol systems, and those most be explained. If some hypothesis about these differences is wrong, then it is rightfully consigned to the trash heap. But then we must come up with some new hypothesis to explain the difference--and there is a difference.

("Postscript: Chimpanzee Culture, 2009," in Laland and Galef, eds., The Question of Animal Culture, 220)

Despite their apparent disagreements, De Waal ultimately has to agree with Tomasello that we must explain the uniqueness of human beings as well as their continuity with other apes. One can see this in what de Waal says about the evolution of morality in Primates and Philosophers. He refers to his experiments on "inequity aversion" among monkeys as showing "a sense of social regularity" or "monkey fairness" (44-45). But then he concedes that this falls short of the full human sense of morality:

Before we speak of "fairness" in this context it is good to point out a difference between this and human fairness, though. A full-blown sense of fairness would entail that the "rich" monkey share with the "poor" one, as she should feel she is getting excessive compensation. Such behavior would betray interest in a higher principle of fairness, one that Westermarck . . . called "disinterested," hence a truly moral notion. This is not the sort of reaction our monkeys showed, though: their sense of fairness, if we call it that, was rather egocentric. They showed an expectation about how they themselves should be treated, not about how everybody around them should be treated. At the same time, it cannot be denied that the full-blown sense of fairness must have started someplace and that the self is the logical place to look for its origin. Once the egocentric form exists, it can be expanded to include others. (48-49; cf. 20, 22, 54-55, 77, 168, 172)

So even as he stresses the continuity of human beings and other primates, de Waal recognizes the uniqueness of the human sense of fairness, which is based on the human capacity for abstract social cognition that extends care for oneself to care for an expanding circle of others. He says that "this rather abstract yet still egocentric concern about he quality of life in a community is what underpins the 'impartial' and 'disinterested' perspective" (172).

To me, this sounds a lot like what Tomasello is saying when he stresses the uniqueness of the human capacity for "shared intentionality," which supports the normative rules and customs of human social institutions, and thus going beyond the behavioral traditions of animal cultures.

No doubt, some of these issues will go into the next version of my "Primate Politics" course at NIU.

The de Waal/Tomasello Debate in Primate Studies

As hard as it is to read the minds of our fellow human beings, it is even harder to read the minds of other animals.

Aristotle's biological works are full of observations about animal minds that qualify him as the first animal psychologist. His general conclusion was that there were traces of almost every human mental ability in other animals, which included emotions, parental care, social learning, communication, imagination, practical judgment, and even something close to intellect. He argued that some animals were capable of voluntary action like that of human children, although they lacked the capacity for deliberate choice that arises in human adults. Some animals are solitary and others gregarious. Of the gregarious animals, some are political. Some of the political animals have leaders. The distinguishing characteristic of the political animals is that they cooperate for some common work or function (koinon ergon). Humans, bees, ants, wasps, and cranes are all political animals in this sense (HA, 488a7-14).

So while human beings are not the only political animals, they are the most political animals, because through speech or reason (logos), they share their conceptions of the advantageous, the just, and the good (Pol, 1253a1-18). Through speech, human beings cooperate for shared ends in ways that are more complex, more flexible, and more extensive that is possible for other political animals. Through speech, human beings can deliberate about the "common advantage" (koinon sumpheron) as the criterion of justice (Rh, 1362a15-63b5). A just political community can be judged to be one that serves the common advantage of all its members, as contrasted with an unjust political community that serves only the private advantage of its ruling group (NE, 1160a13-14; Pol, 1279a17-19).

Aristotle's comparative animal psychology includes the observation that monkeys and apes belong to intermediate species close to human beings in that they "share in the nature of both a human being and the quadrupeds" (HA, 502a16). From his anatomical comparisons, which included dissections of monkeys and apes, he concluded that in their feet, legs, hands, face, teeth, and internal parts, the apes are humanlike (HA 502a17-b27; PA, 689b1-35).

And yet, in relying on direct observations of animal behavior and anatomical dissection, Aristotle, like any animal psychologist, had no direct access to the animal mind. With human beings, he had the data of speech, and thus he could study human politics through the study of political rhetoric in which human beings debate their opinions about political life. Other animals communicate in other ways, but this animal communication is often not as rich as human speech, although Aristotle observed the waggle dance of bees, which we now know to be a remarkably complex form of abstract communication.

The fundamental problem is that the social reality of animal life--including human life--is a mental construction of the animal mind that goes beyond the physical reality of the directly observable world. To understand that mental construction of social reality, we have to draw from our inward subjective experience of our minds and our intersubjective world of symbolism. From our observation of animal behavior, we can project some of our mental experience onto them, but we can never be sure how accurate this is.

We have to assume, as Aquinas said, that "the internal passions of animals can be gathered from their outward movements" (ST, I-II, q. 34, a. 4). But then, as Darwin observed in The Descent of Man, in trying to understand the evolution of human mental abilities from the mental powers of our animal ancestors, we face "the impossibility of judging what passes through the mind of an animal" (Penguin ed., 105).

Over the past hundred years, we have had more systematic study of primate behavior and cognition than was done previously. And over the last forty years, we have seen some methodologically sophisticated studies of primates both in the wild and in captivity, and the captive studies have included controlled, and often ingenious, experimentation. But with all of this primate research, we still face the same problem: primate social reality is a construction of animal minds, and judging what passes through those minds is always speculative and uncertain.

Consider, for example, the many news reports this week--in the New York Times and elsewhere--of new experiments that appear to show chimpanzee generosity. Frans de Waal and his colleagues at Emory University claim to show "spontaneous prosocial choice by chimpanzees." Experiments by other groups suggest that chimpanzees are not very helpful to one another, although observations of chimpanzees in the wild suggest the opposite. De Waal has trained his chimpanzees at the Yerkes National Primate Research Center to exchange tokens for food. In this experiment, chimpanzees were paired up and placed in adjoining cages. One chimp could choose a token from a bucket, with tokens of two different colors. One color would exchange for food for oneself but not for the other chimp. The other color would exchange for food for oneself and for the other chimp. In a majority of cases, the chimp would choose the generous option.

Notice the odd features of this experiment. The participants were seven adult female chimps. We must wonder how much we can conclude from the behavior of seven individuals. We must also wonder why only females were tested, particularly since much of the seemingly cooperative behavior among chimps in the wild is male behavior--such as group hunting and warfare. We might question how much generosity we really see here. The report is that the generous tendency for each individual chimp ranged from 52.9% to 66.7%. That suggests that for some of these individuals the choice of tokens was almost random. And even those showing the more generous tendency are not bearing any costs in their generosity.

As indicated in the New York Times article, this research report has been criticized by Michael Tomasello, Co-Director of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. Anyone who follows this kind of research knows that Tomasello and de Waal have been on opposite sides of a debate for many years. Most recently, Tomasello and his colleagues have published a study in Nature arguing that "collaboration encourages equal sharing in children but not in chimpanzees." They show that children around the age of three show equitable distribution of resources with those engaged in collaborative activities, but chimps do not exhibit such equal sharing with collaborative partners. They offer this as evidence for a general theory of human evolution: the uniquely human propensity for social norms of fairness and equity arose among human ancestors who shared resources after collaborative foraging, and the ancient evolutionary propensity arises early in the development of children as an evolutionarily natural trait.

De Waal and Tomasello agree in general that human nature can be explained as a product of evolutionary primate history, so that human beings are similar to their closest living relatives--chimpanzees and bonobos--but also quite different in humanly unique ways. And yet de Waal and Tomasello disagree in their emphasis--de Waal emphasizing the similarities, Tomasello emphasizing the differences--a disagreement that runs through much of the primate research.

This disagreement was evident a few years ago when de Waal and his colleague Sarah Brosnan gained wide publicity for a report in 2003 entitled "Monkeys Reject Unequal Pay," which seemed to show that capuchin monkeys had a "sense of fairness." Having been trained to exchange tokens for food, the monkeys seemed to be engaged in economic exchange, which is why this kind of research has gained attention from economists. In an experiment to test for "inequity aversion," monkeys who offered a token for food would receive either a slice of cucumber or a grape, and the monkeys clearly favored the grape as more desirable. If one monkey got a slice of cucumber, while seeing that another monkey nearby got a grape, the monkey apparently protested against this, either by refusing to exhange the tokens or by throwing away the cucumber. It seemed as though the monkey was protesting "unequal pay."

But again we might wonder about some of the features of this research. The report was based on the behavior of only five females. Apparently, males had not shown "inequity aversion." We have to wonder then how far we can go in drawing general conclusions from this experiment.

Moreover, as some critics noticed, it was possible that the monkeys weren't showing "inequity aversion" but only frustrated expectations. If a monkey receives a cucumber slice, while noticing that grapes are available, she might feel frustration at not getting the more desirable food, but this would have nothing to do with "unequal pay." Other critics suggested that a monkey perceiving inequity in the distribution of food would want more cucumber slices, not less, to compensate for the inequity.

We might also ask whether these monkeys were really showing a sense of fairness. Even if we are persuaded that the monkey receiving the less favored food was showing indignation in protesting the inequity from the other monkey getting the more favored food, there is no evidence that the monkey getting the unfair advantage felt any guilt. If the monkeys receiving grapes were to throw away their grapes to show sympathy for those receiving only cucumbers, that would be a far more impressive display of a sense of justice.

A few years later, de Waal and Brosnan tried to answer some of these criticisms with new experiments using chimpanzees. They reported that chimps also showed inequity aversion, although chimps in close social relationships were more tolerant of inequity. And yet, once again, Tomasello and other critics pointed out weaknesses in this report. For example, of the 20 individuals studied, 14 refused inequitable exchanges in less than 2% of the trials, which is not very impressive.

Tomasello and his colleagues did a study of their own with 7 orangutans, 6 gorillas, 4 bonobos, and 13 chimpanzees in which the behavior seemed to show that there was no inequity aversion, and thus contradicting de Waal and Brosnan's research.

Some of the details in this debate are surveyed in an article by Kenneth Krause for eSkeptic.

As compared with what de Waal does, Tomasello's research is more interesting in that he performs similar experiments with chimpanzees and young children to see how and at what age the children surpass the chimpanzees. This allows him to argue that the early development of human children replicates human evolutionary history: we see the children starting out with chimpanzee-like abilities but then quickly moving to the uniquely human capabilities that arose early in human evolution. In this way, ontogeny might recapitulate phylogeny.

Some good videos of this research with both chimpanzees and children can be found here. There is also a good PBS Nova video on this and related research by Tomasello and others.

Tomasello's work is embedded within a general social theory of cooperation, which is well summarized in his book Why We Cooperate (MIT Press, 2009). One can see the influence on Tomasello of John Searle's The Construction of Social Reality (Free Press, 1995). Searle argues that we need to understand how social reality differs from physical reality, because social reality is a construction of the mind through the "collective intentionality" of "we consciousness" as opposed to the "I intentionality" of "I consciousness." In social life, we collaborate with one another as we create institutional practices in acting intentionally for shared goals. We thus create "institutional facts" that are just as real as "brute facts" or physical facts, although these institutional realities depend on the work of our minds, and they are not directly observable the way physical reality is directly observable. Tomasello picks up this idea in arguing that human beings are unique in their capacity for "shared intentionality," which allows human beings through their symbolic capacities to engage in cultural niche construction in ways that far surpass chimpanzees and other primates.

What Tomasello is doing is that he's exploring in experimental ways the evolutionary basis for what Aristotle and Aquinas saw--that we are similar to other social and political animals, and yet we are unique in our capacity to use our conceptual and linguistic abilities to create social worlds of shared intentionality that go beyond anything seen in the rest of the animal world.

Tomasello's comparative studies of chimpanzees and children follows in the tradition of Darwin, who methodically studied one of his infant children and compared the child with monkeys and apes to see when the child showed the moral sense that Darwin thought was uniquely human.

If you really want to probe into de Waal's mind, you'll have to go to the video of his interview on "The Colbert Report."

I will be writing more posts this month on the de Waal/Tomasello debate.

Some posts on related topics can be found here, here, here, here, here, and here.

REFERENCES
Brauer, Juliane, Josep Call, and Michael Tomasello, "Are Apes Really Inequity Averse?" Proceedings of the Royal Society B 273 (2006): 3123-3128.

Brosnan, Sarah F., and Frans de Waal, "Monkeys Reject Unequal Pay," Nature 425 (18 September 2003): 297-99.

Brosnan, Sarah F., Hillary C. Schiff, and Frans de Waal, "Tolerance for Inequity May Increase with Social Closeness in Chimpanzees," Proceedings of the Royal Society B, 272 (2005): 253-58.

Hamann, Katharina, Felix Warneken, Julia Greenberg, and Michael Tomasello, "Collaboration Encourages Equal Sharing in Children But Not in Chimpanzees," Nature, early online publication, July, 2011.

Horner, Victoria, J. Devyn Carter, Malini Suchak, and Frans de Waal, "Spontaneous Prosocial Choice by Chimpanzees," Proceedings of the National Academy of Sciences, early edition, August, 2011.

Thomistic Natural Law as Darwinian Natural Right: An APSA Paper

On September 1, at 2:00 pm, I will be on a panel ("Biology and Rights") at the 2011 Meetings of the American Political Science Association in Seattle.

My paper is "Thomistic Natural Law as Darwinian Natural Right: Replies to Critics." It can be downloaded.

Some of the material in this paper has been pulled from various posts on this blog.

Under the title "What Nature Has Taught All Animals," I summarize some of the common ground between Thomistic natural law and Darwinian natural right.

I then reply to six objections that have been raised by my critics:

(1) It is said that I fail to see that natural law depends on a divine lawgiver as its source.

(2) Darwinian science denies the natural teleology that is required for natural law.

(3) Darwinian science denies the reality of species as the ground of natural law.

(4) Darwinian natural right denies human freedom by denying the freedom of reason in ruling over the human desires or emotions.

(5) Darwinian explanations of human nature ignore the importance of culture and habituation in shaping human character.

(6) Darwinian naturalism is self-defeating, because in denying that the human mind was created in God's image, and asserting that the mind arose from a mindless process of evolution, it gives us no reason to trust our mental capacity for true beliefs.

My general claim is that by rooting natural law in a scientific conception of human nature, and by avoiding the contradictions that arise from Thomas Aquinas's occasional efforts to elevate revelation over reason, Darwinian natural right is the natural fulfillment of Thomistic natural law.

Mind Is Not the Only Possible First Cause of All Things: Hume, Darwin, and Strauss

The most common objection to my arguments for Darwinian natural right is that Darwinian science fails to see that the only possible first cause of natural order--including natural moral order--is divine Mind. So, for example, Francis Beckwith criticizes me for not recognizing that "natural law and our human nature have their source in Mind." This reasoning that the apparently designed order in the world points to a cosmic Intelligent Designer has a long tradition--from Plato's Laws to Aquinas's natural theology to the proponents of "intelligent design theory" at the Discovery Institute.

I agree that this is one possible explanation for the uncaused cause of all natural order. I agree that this satisfies our natural desire for religious understanding by appealing to our evolved instinct for projecting the human mind onto the world. But affirming this possibility as true is an act of religious faith, not of rational demonstration. This religious belief in an intelligently designed cosmos can be neither proven nor refuted by natural reason.

It is possible, therefore, for the theistic believer to be a theistic evolutionist, believing that the Intelligent Designer has used the natural evolutionary process to carry out His plan. C. S. Lewis, Alvin Plantinga, and many other theists have taken this position. But, again, this is an act of faith rather than reason.

Affirming the existence of a divine Mind as the intelligent designer of cosmic order cannot be proven by reason, because this is only one possibility among many that we can draw from our natural experience of order. Since there are many different principles of order that we might use to explain the cosmic order of nature, and since there is no demonstrative proof that one principle is better than all the others, we are left in a state of skeptical doubt.

As I have indicated in some recent posts, the supposed proof for the existence of a divine Mind depends on an anthropomorphic analogy of mental agency, which assumes that the natural order of the cosmos is an artifact that points to the mental agency of a divine artisan. Leo Strauss rejected this analogy in suggesting other possibilities: "One realizes the possibility that the first things originate all other things in a manner fundamentally different from all origination by way of forethought. The assertion that all visible things have been produced by thinking beings or that there are any superhuman thinking beings requires henceforth a demonstration, a demonstration that starts from what all can see now" (NRH, 89).

In this passage, Strauss doesn't explain what this alternative possibility is. But in his 1948 lecture on "Reason and Revelation," he did identify Darwin's evolutionary science as an alternative to divine creationism, and thus he put Darwinism on the side of reason against revelation.

In Cicero's De Natura Deorum, Cotta suggests various alternatives to Platonic and Stoic intelligent-design cosmology. In Hume's Dialogues Concerning Natural Religion, Philo lays out more clearly what these alternative possibilities might be, and he suggests the possibility of evolution by natural selection.

In the Dialogues (part 7), Philo argues that any attempt to explain the order of the universe depends on reasoning by analogy, where we look for some likeness between the order of the universe and the order of those things that we know by experience. Thus we must project the order of some small part of nature onto the whole of the natural universe.

Philo suggests that there are at least four such principles--reason, vegetation, instinct, and generation. The natural theology of intelligent design rests on the principle of reason as the source of order. From our experience with human mental agency in designing things and carrying out those designs, we might infer that the whole universe is the design of a mental agent. But we might just as easily employ the principles of vegetation, instinct, or generation. Plants grow from seeds and develop into intricately complex organisms. Animals engage in complex behaviors that manifest instinct. Animals generate offspring that grow into fully formed adults. In each case, we see principles of natural order that don't require reason. In fact, reason itself seems to be produced by animal generation, so that generation is prior to reason.

Philo observes:

To say that all this order in animals and vegetables proceeds ultimately from design is begging the question; nor can that great point be ascertained other wise than by proving a priori, both that order is, from its nature, inseparably attached to thought, and that it can never, of itself, or from original unknown principles, belong to matter.

It all depends on judging likenesses:

The world, say I, resembles an animal, therefore it is an animal, therefore it arose from generation. The steps, I confess, are wide; yet there is some small appearance of analogy in each step. The world, says Cleanthes, resembles a machine, therefore it is a machine, therefore it arose from design. The steps are here equally wide, and the analogy less striking.

Or maybe the world was spun out by a cosmic spider:

The Brahmins assert that the world arose from an infinite spider, who spun this whole complicated mass from his bowels, and annihilates afterwards the whole or any part of it, by absorbing it again, and resolving it into his own essence. Here is a species of cosmology, which appears to us ridiculous; because a spider is a little contemptible animal whose operations we are never likely to take for a model of the whole universe. But still here is a new species of analogy, even in our globe. And were there a planet wholly inhabited by spiders (which is very possible), this inference would there appear as natural and irrefragable as that which in our planet ascribes the origin of all things to design and intelligence, as explained by Cleanthes. Why an orderly system may not be spun from the belly as well as from the brain, it will be difficult for him to give a satisfactory reason.

Later (in part 8), Philo comes close to formulating Darwin's theory of evolution:

It is in vain, therefore, to insist upon the uses of the parts in animals or vegetables and their curious adjustment to each other. I would fain know how an animal could subsist, unless its parts were so adjusted? Do we not find, that it immediately perishes whenever this adjustment ceases, and that its matter corrupting tries some new form. It happens, indeed, that the parts of the world are so well adjusted, that some regular form immediately lays claim to this corrupted matter: and if it were not so, could the world subsist? Must it not dissolve as well as the animal, and pass through new positions and situations; till in a great, but finite succession, it falls at last into the present or some other order?

It seems that what Darwin later developed in the theory of evolution specified what Hume considered a theoretical possibility.

And yet both Hume and Darwin (and Hume's character Philo) indicated that there was some plausibility to the design argument as based on the analogy to the human mind. In the Treatise on Human Nature, Hume declared: "The order of the universe proves an omnipotent mind." In the Natural History of Religion and the Dialogues, Hume acknowledges the power of the argument from design in supporting "true religion" or "philosophical theism," even as he exposes the weaknesses in such reasoning by anthropomorphic analogy.

Similarly, in his Autobiography, Darwin said that he often felt compelled "to look to a First Cause having an intelligent mind in some degree analogous to that of man; and I deserve to be called a Theist." But one page later, he concludes: "The mystery of the beginning of all things is insoluble by us; and I for one must be content to remain an Agnostic." Then, on the next page, he says that by the end of his life, he was governed by "scepticism or rationalism."

Does the powerful appeal of the argument from intelligent design show the power of our evolved natural instinct for religious understanding, which shows the working of what Justin Barrett and Jesse Bering identify as our "hyperactive agency detection device"?

In any case, Hume, Darwin, and Strauss show us that we can challenge that religious instinct by showing that the argument from intelligent design rests on an indemonstrable analogy. The natural desire for religious understanding is checked by the natural desire for intellectual understanding. We must choose between revelation and reason.

Some related posts can be found here here, here, here, and here.

John Locke's Biological Naturalism

Leo Strauss and many of those influenced by Strauss have assumed that John Locke's political philosophy rejected the rule of nature in favor of the rule of convention. They have concluded from this that Lockean liberal thought generally has no ground in nature and thus prepares the way for modern relativism and nihilism. This reading of Locke is mistaken because it fails to recognize that in criticizing the Platonic naturalism of eternal essences, Locke is defending a biologically empirical science of natural history that points back to Aristotle and ahead to Darwin.

In Natural Right and History, Strauss insists that Locke's political philosophy is a revolutionary break with the philosophic tradition of classic natural right.

Through the shift of emphasis from natural duties or obligations to natural rights, the individual, the ego, had become the center and origin of the moral world, since man--as distinguished from man's end--had become that center or origin. . . . The world in which human creativity seems to reign supreme is, in fact, the world which has replaced the rule of nature by the rule of convention. From now on, nature furnishes only the worthless materials as in themselves; the forms are supplied by man, by man's free creation. For there are no natural forms, no intelligible "essences": "the abstract ideas" are "the inventions and creatures of the understanding, made by it for its own use." Understanding and science stand in the same relation to "the given" in which human labor, called forth to its supreme effort by money, stands to the raw materials. There are, therefore, no natural principles of understanding: all knowledge is acquired; all knowledge depends on labor and is labor. (pp. 248-49)

Against this claim that Locke denies "the rule of nature," we might notice Locke's constant appeals to "the principles of human nature," which include the natural desires for survival, reproduction, social life, and knowledge, as expressing the natural pursuit of happiness as the ultimate end of human action (FT, 88-97; ST, 10, 67). "The highest perfection of intellectual nature lies in a careful and constant pursuit of true and solid happiness" (ECHU, 2.21.52).

In recognizing this Lockean appeal to human nature and the nature of human happiness, I agree with Tom West and with Peter Myers in his book Our Only Star and Compass: Locke and the Struggle for Political Rationality (Rowman and Littlefield, 1998).

Strauss assumes that in criticizing reasoning about "essences," Locke is rejecting the reality of "natural forms" altogether. But Strauss fails to see how this Lockean skepticism about Platonic essentialism is grounded on an empirical science of biological natural history that goes back to Aristotle, which was to be fulfilled by Darwinian evolutionary science.

In the Essay Concerning Human Understanding, Locke rejects those scholastic proponents of reasoning about eternally fixed essences, because they "suppose their words to stand also for the reality of things," and because they understand natural science to consist in "the bare contemplation of . . . abstract Ideas" (3.2.5; 4.12.9). By contrast, Locke argues, "to define names right, natural history is to be enquired into; and their properties are, with care and examination, to be found out" (3.11.24).  Rather than studying human understanding through the logical analysis of mental abstractions, Locke relies on "this historical, plain method" of reasoning from observational experience of what actually happens (Intro., 2).

Rather than deductive reasoning from supposedly eternal and fixed "essences," Locke thus appeals to natural history as the way to understand "the nature of things themselves" through experience and observation. Such knowledge does not permit demonstration and certainty, but it does provide probabilistic knowledge. We can thus know "the regular proceedings of causes and effects in the ordinary course of nature," and this we call "an argument from the nature of things themselves" (4.16.6). Nature is so highly variable and contingent that we cannot reliably discover the unchanging essences sought by the scholastics. But we can discover with some probability the regular patterns in the natural world. "I would not here be thought to forget, much less to deny, that nature in the production of things, makes several of them alike: there is nothing more obvious, especially in the races of animals and all things propagated by seed" (3.3.13).

This reference to the natural order of the living world of plants and animals is significant because it manifests Locke's biological understanding. Locke was a medical doctor and medical researcher. In his personal library, he had more medical books than books of philosophy. He was an associate of Thomas Sydenham, the most prominent medical doctor and researcher of his time, who promoted medicine as an empirical science of natural history. Similarly, Locke's philosophical science of human nature was an empirical, probabilistic science that looked for recurrent patterns in the variable phenomena of human thought and action, a science of life that could be traced back to Aristotle and that was carried forward by Darwin.

That Locke is drawing from the Aristotelian biological tradition of understanding species is evident when one notices the passages in the Essay that are almost direct quotations from Aristotle's biological writings.  For example, Locke's comments on how "we shall find everywhere that the several species are linked together, and differ but in almost insensible degrees" (3.6.12; 4.16.2) echo passages in Aristotle's Part of Animals (681a10-15).  Like Locke, Aristotle is criticizing the Platonic tradition of essentialism in defending a biological concept of species rooted in an empirical science of natural history.

Some related posts can be found here, here, here, here, here, here, and here.

Does Gay Marriage Perform the Functions of Marriage?

The "Sunday Styles" section of yesterday's New York Times has a collection of articles on how gays are responding to the legalization of gay marriage in New York State. The recurrent theme is how gay marriage might satisfy the same social needs that are satisfied by heterosexual marriage.

For example, one article by Lisa Belkin is entitled "For the Sake of the Children." Gay men and lesbians want to legalize their marriages as a way of securing their attachment to their children. One mother is quoted as saying, "We feel like we're marrying the kids."

But is this really true? Is the legalization of gay marriage warranted because it performs the same functions as heterosexual marriage?

On his blog, Empedocles denies this in two recent posts on the function of marriage and on answering the arguments for gay marriage.

He argues that the evolutionary function of marriage is to solve the problems that arise from heterosexual intercourse--particularly, the need for producing and rearing children. Since the function of marriage as a social institution is to solve this problem, and since gay marriage would not serve this function, it is just for government to legalize heterosexual marriage but not gay marriage. This does not violate the "equal protection" clause of the United States Constitution, because equal treatment allows for discrimination against those people who lack the qualifications relevant to performing a social function, and gays cannot perform the function of producing and rearing children.

For me, this argument raises three sets of questions.

(1) Do gay marriages perform the function of producing and rearing children? For some gays, the primary purpose of gay marriage is to support the bond between gay parents and their children. Are they wrong about this? If they are, does this imply that gay parenting should be illegal, because gay parenting cannot properly perform the social function of producing and rearing children?

(2) Do childless marriages perform the function of securing conjugal bonding? Many gay marriages will be childless. But, of course, many heterosexual marriages are childless. If Empedocles is right about marriage having only one function--producing and rearing children--then any childless marriage is not really a marriage. Is there any socially relevant difference between a childless heterosexual marriage and a childless gay marriage?

Is conjugal bonding a distinct function of marriage? If so, does that mean that reinforcing the exclusive sexual bond of the marriage partners allows marriage to solve the social problems associated with sexual mating? Has evolution produced conjugal bonding as a natural desire distinct from parental care?

(3) Does marriage require governmental licensing? Empedocles seems to assume that the social institution of marriage cannot function without a system of governmental licensing by which the government acts as the "describer" in specifying what counts as a marriage. But then he also speaks of how "social stigma" is often the most effective means for holding partners to their marriage vows and their parental duties. If so, does that mean that marriage as a social institution depends mostly on the social norms of civil society rather than the laws of the state? Throughout most of human history, marriage has been enforced by social practices without governmental licensing. Does this suggest the possibility of "privatizing" marriage, so that the norms of marriage would be determined by families, churches, and other social institutions without the necessity of getting a license from government?

Some posts on "Darwinian marriage" can be found here, here, and here.

Cicero, Aquinas, and Intelligent Design Anthropomorphism

Darwinian natural right is the natural fulfillment of Thomistic natural law, because it shows how natural law can be truly natural in so far as it is rooted in evolved human nature, without any necessity for appealing to theistic faith, and thus Darwinian natural right escapes the incoherence of Thomistic natural law.

Thomas Aquinas's natural law teaching suffers from a fundamental incoherence. On the one hand, Aquinas distinguishes natural law from divine law, just as he distinguishes what we can know by natural reason from what we can know only by divine revelation. Although divine law can reinforce natural law for those who are religious believers, natural law can stand on its own natural ground, because it is comprehensible to human beings by their natural experience of their natural inclinations and natural reason, regardless of whether they are religious believers. On the other hand, however, Aquinas embeds his teaching on natural law within a Christian theological teaching in a way that suggests that natural law depends on divine law. But in that case, it seems that natural law is not truly natural. Even the term natural law suggests this by suggesting that there must be a divine lawgiver. Consequently, Leo Strauss and his students have criticized Thomistic natural law as a betrayal of classic natural right.

The Darwinian account of the natural moral sense fulfills Thomistic natural law by grounding it in evolved human nature without any necessity for a theistic cosmology. In doing that, the Darwinian account follows in a tradition of Socratic/Ciceronian skepticism about the theistic cosmology of intelligent design, a tradition that stretches from Cicero's De Natura Deorum to Hume's Dialogues Concerning Natural Religion.

One can see what's at issue here by noticing the one place in the Summa Theologica where Aquinas refers to Cicero's De Natura Deorum. Aquinas is arguing that we must see the world as governed by God when he writes:

Certain ancient philosophers denied the government of the world, saying that all things happened by chance. But such an opinion can be refuted as impossible in two ways. First, by observation of things themselves. For we observe that in nature things happen always or nearly always for the best, which would not be the case unless some sort of providence directed nature towards good as an end, which is to govern. Wherefore, the unfailing order we observe in things is a sign of their being governed. For instance, if we enter a well-ordered house, we gather therefrom the intention of him that put it in order, as Tullius says (De Nat. Deorum ii), quoting Aristotle. Secondly, this is clear form a consideration of divine goodness. . . . (I, qu. 103, a. 1)

Although Aquinas refers to Cicero hundreds of times in his writings, he refers to the De Natura Deorum only three times, and this is the only reference to the book in the Summa Theologica. That's surprising. Since this book is one of the most important statements on ancient theological cosmology, one might think that Aquinas would need to consider this book as he lays out his own theological cosmology. We might explain this, however, by noting that this book contains the most explicit and rigorous attacks on theological cosmology as based on intelligent design reasoning. Aquinas never defends his own theological cosmology against these attacks.

The radical character of the skeptical attack on religion in Cicero's book is indicated by the fact that Hume followed the style and substance of Cicero's book in his own Dialogues Concerning Natural Religion, which was published after Hume's death because of his fear of persecution. Hume's skepticism about natural theology and the intelligent design argument was continued by Darwin in defending his theory of natural evolution against the theory of special creation.

In the passage above, Aquinas is referring to a defense of Stoic intelligent-design cosmology in Cicero's book coming from Balbus (2.15-17, 87, 95). Remarkably, Aquinas is silent about the vigorous refutation of Balbus's reasoning coming from Cotta, a Roman priest who is also an Academic skeptic. Moreover, Aquinas never responds to Cotta's criticisms of the sort of intelligent-design reasoning that Aquinas himself adopts.

Aquinas restates Balbus's claim that the only alternative to explaining the world as intelligently designed by God is to say that everything happens by chance. But Cotta insists that there's another possibility--that we can explain nature's order as a product of nature itself in which things emerge by the spontaneous order of natural processes without any need to assume a divinely intelligent mind at work. "But not all things, Balbus, that have fixed and regular courses are to be accredited to a god rather than to nature" (3.24).

Furthermore, Cotta indicates, Balbus's intelligent-design reasoning assumes a ridiculous anthropomorphic analogy by which we assume that the whole world is an artifact that implies the existence of a divine artist. Aquinas refers to Balbus's house analogy, which Cotta ridicules:

He says, "If we saw a beautiful house, we should infer that it was built for its masters, and not for mice; so therefore we must regard the world to be the house of the gods." Assuredly, I should so regard it, if I thought it had been built like a house, and not constructed by nature, as I shall show that it was.

Cotta challenges Balbus to prove that we must explain the world as analogous to a human artifact. Like Balbus, Aquinas assumes the plausibility of this analogy without proof. When Aquinas sets out his proofs for the existence of God, one of the objections he considers is: "For all natural things can be reduced to one principle, which is nature; and all voluntary things can be reduced to one principle, which is human reason or will. Therefore, there is no need to suppose God's existence." Aquinas replies: "Since nature works for a determinate end under the direction of a higher agent, whatever is done by nature must needs be traced back to God, as to its first cause" (I, q. 2, a. 3, ad 2). Thus, Aquinas assumes that our natural experience with human agency can be anthropomorphically projected onto the world as the work of a "higher agent." 

Aquinas makes it clear that natural theology depends on the plausibility of this anthropomorphic analogy of intentional artifice: "In all things moved by reason, the order of reason that moves them is evident, although the things themselves are without reason.  For an arrow through the movement of the archer goes straight towards the target, as though it were endowed with reason to direct its course.  The same may be seen in the movements of clocks and all engines put together by the art of man.  Now as artificial things are in comparison to human art, so are all natural things in comparison to the divine art" (ST, I-II, q. 13, a. 2, ad 3).

Cotta indicates the many problems with this anthropomorphism of intelligent-design cosmology. We know by natural experience how human minds work in executing human intelligent design. But we know nothing about how divine minds could work to create the world. Human minds are always embodied. But it's ridiculous to think that the gods have human bodies, with the mortality and other limitations that come with embodiment. We might say that the gods are disembodied minds. But then it's inconceivable how a mind could have any knowledge without bodily senses.

It's not clear that Aquinas ever responds to such criticisms. Of course, his response might be that our understanding of the Divine Mind requires faith in divine revelation, and "faith and science are not about the same thing," because "the reasons employed by holy men to prove things that are of faith are not demonstrations" (II-II, q. 1, a. 5). But if that's his response, that only confirms Cotta's complaint that intelligent-design cosmology is not based on rational proof but on religious belief.

The ancient Christian writer Lactantius observed: "Cicero was aware that the objects of men's worship were false. For after saying a number of things tending to subvert religion, he adds nevertheless that these matters ought not to be discussed in public, lest such discussion destroy the established religion of the nation" (Divine Institutions, 2.32).

Does this explain Aquinas's reticence--that it was not good to publicly discuss the flaws in intelligent design cosmology, because this might subvert religious and political order?

Cicero has Cotta indicate in De Natura Deorum that Plato and other philosophers had developed intelligent-design cosmology as a noble lie to support popular morality and political order, a noble lie that the philosophers knew to be a lie (1.30, 77). In his Academica, Cicero has Varro argue that when Socrates turned away from cosmology to the study of the human things, this suggested that cosmology has nothing to do with the human good (1.15). Similarly, Cotta suggests that natural right has nothing to do with the cosmos or the gods, because it depends on human social life and on a naturally instinctive conscience by which human beings judge what is right and wrong for human life (3.38, 85).

Darwin deepened this understanding by showing how the "conscience or moral sense" could be explained as arising from the naturally evolved spontaneous order of human instincts, human customs, and human judgments.

And yet Darwin recognized that religious belief could be important for reinforcing this natural moral sense. He also recognized that the natural human desire for ultimate explanation leaves us with a fundamental choice between nature and God as the unexplained ground of all explanation, and thus he left open the unresolved conflict between reason and revelation.

Recent research in the evolutionary psychology of morality confirms and deepens each of these points concerning the evolved instinctive basis of morality, religious understanding, and intellectual understanding.

A good article on Cicero, Aquinas, and natural law is Adam Seagrave's "Cicero, Aquinas, and Contemporary Issues in Natural Law Theory" (THE REVIEW OF METAPHYSICS, vol. 62, March, 2009, pp. 491-523). Seagrave's argues--correctly, I think--that one can see how Thomistic natural law need not depend upon Christian beliefs if one sees it as a continuation of Ciceronian natural law, which was based on an Aristotelian understanding of human nature. Seagrave does not say enough, however, about the crucial issue of Stoic theological cosmology. He points to "the Stoic cosmology which serves as the foundation for the natural law, a cosmology which had been discredited by Cicero himself in his DE NATURA DEORUM and has been widely discarded since Cicero's time." But Seagrave does not reflect on the point that Aquinas embraced a Christian version of the Stoic cosmology. Nor does Seagrave reflect on the possibility that the Darwinian rejection of an anthropomorphic moral cosmology fulfills Cicero's suggestion that natural law need not depend on such a cosmology.

Some previous posts on related topics can be found here, here, here, and here.

Are Honeybees Created in God's Image?

In commenting on my previous post on Alvin Plantinga's evolutionary argument against naturalism, "Empedocles" pointed out that the honeybee waggle dance is a dramatic example of how evolution by natural selection favors adaptive behavior that tracks the truth about the world.

This suggests that we can account for the natural evolution of reliable cognitive faculties without assuming a theistic explanation of human mental capacity as a product of divine creation in the image of God.

Plantinga implicitly concedes this point when he acknowledges that natural evolution tends to produce "accurate indicators." But then he insists that this has nothing to do with "true beliefs." He offers no evidence, however, for this assertion that the evolution of "accurate indicators" has nothing to do with the evolution of "true beliefs" in animals with complex nervous systems (like human beings).

Even without attributing any conscious beliefs to honeybees, the remarkable accuracy of their waggle dance illustrates how natural evolution--even without divine guidance--can produce animal cognition and communication that shows an accurate representation of the world as related to the needs of the animal.

Or would Plantinga argue that this can only be explained as the work of God--that the cognitive abilities of honeybees show that they have been created to some degree in the image of God?

The waggle dance of honeybees can be seen in a YouTube video.

Plantinga's Evolutionary Argument Against Naturalism

One of the primary doctrines of traditional theism is that God created human beings in His image. And if God is pure Mind, that suggests that it is primarily in the human mind that we see that divine image.

That's Thomas Aquinas's teaching. "Since human beings are said to be in the image of God in virtue of their having a nature that includes an intellect, such a nature is most in the image of God in virtue of being most able to imitate God" (ST, I, q. 93, a. 4). "Only in rational creatures is there found a likeness of God which counts as an image. . . . As far as a likeness of the divine nature is concerned, rational creatures seem somehow to attain a representation of that type in virtue of imitating God not only in this, that he is and lives, but especially in this, that he understands" (I, q. 93, a. 6).

One of the best arguments for theism is that this theistic doctrine of the human mind as created by God in His image provides the necessary support for the validity of human thought, including the validity of modern science. If we embrace Naturalism--the view that nothing exists except Nature, and so there is no God or nothing like God--we are caught in self-contradiction: if human thought originated not from a divine Mind but from the irrational causes of Nature, then we cannot trust our minds as reliable, and thus we cannot trust our belief in Naturalism. Naturalism destroys itself by destroying the rationality of believing in Naturalism, or anything else. Insofar as science--including evolutionary science--depends on the validity of human thought, and insofar as theism is the indispensable support for trusting in the validity of human thought, science is not only compatible with theism, science depends upon theism.

When I was a college freshman, I first learned this argument from reading C. S. Lewis's book Miracles, and it impressed me as one of the most powerful arguments for theism. 25 years later, as a college professor, I heard Alvin Plantinga present a more sophisticated version of the same argument when he gave a seminar presentation at my university on his paper "Naturalism Defeated."

I agree with Lewis and Plantinga that theistic religion and evolutionary science are compatible, because while science requires a methodological naturalism, it does not require the metaphysical naturalism that denies theism. I also agree with them that the theistic belief in the divine creation of the human mind can support our confidence in scientific reasoning, including evolutionary reasoning. But I disagree with their claim that evolutionary science is self-contradictory or incoherent without theism.

Plantinga has presented his argument in various writings, including the paper "Naturalism Defeated." A short summary of the argument is in the Introduction to Naturalism Defeated?: Essays on Plantinga's Evolutionary Argument against Naturalism, edited by James Beilby (Cornell University Press, 2002), which includes critiques of the argument by various authors and Plantinga's reply to the critiques. One of the best critiques in this volume is Evan Fales, "Darwin's Doubt, Calvin's Calvary." Plantinga's argument also comes up in his debate with Daniel Dennett in their recent book Science and Religion: Are They Compatible? (Oxford University Press, 2011).

Without going into all the technical details that are so dear to the hearts of analytic philosophers, here's the core of the argument in four steps.

(1) If we understand naturalism as the belief that there is no God--no supernatural Mind outside of Nature that created Nature--and if the naturalist is also a Darwinian who believes that evolutionary science explains the origins of all life, including human life, then the Darwinian naturalist must believe that the mental faculties of human beings originated through evolution by natural selection favoring those random mutations that were adaptive for survival and reproduction.

(2) Natural selection rewards adaptive behavior and punishes maladaptive behavior. But natural selection does not care about the truth or falsity of an animal's beliefs. If beliefs produce adaptive behavior, they will be rewarded by natural selection regardless of whether the beliefs are true or false. Therefore, the evolution of adaptive behavior in our prehistoric ancestors did not guarantee or make it probable that our cognitive faculties would be reliable in generating mostly true beliefs.

(3) From this it follows that the Darwinian naturalist has no good reason to trust his cognitive faculties as reliable. But then it follows that the Darwinian naturalist has no good reason to feel confident that his belief in naturalism is true. Consequently, Darwinian naturalism is self-defeating in that it contradicts itself.

(4) Darwinian science--and science generally--can escape this self-defeating position by rejecting naturalism and accepting theism, because theism believes that our human minds were created by God in His image such that we can understand the intelligible world He has created, and therefore we can be confident in the reliability of our divinely created cognitive faculties. This is compatible with evolutionary science, because we can assume that God has guided the evolutionary process, perhaps by causing those random mutations that He foresaw as facilitating the evolution of the human mind in its capacity for correctly understanding the world. This is also necessary for evolutionary science because it supports our confidence in the validity of human reason and escapes the incoherence of naturalism.

Like Lewis, Plantinga is a theistic evolutionist. He accepts the truth of Darwinian evolutionary science, because he believes that God could have used the evolutionary process to carry out his creative plan, which required miraculous acts by God to guide the evolutionary process towards human beings as having minds manifesting the intellectual image of God.

Dennett and other critics of Plantinga have objected that science requires naturalism, because in all scientific inquiry, the scientist must assume that everything can be explained by natural regularities or laws that are never broken by miraculous events. Otherwise, every regularity or law of science would have to be stated with the qualification unless God performs a miracle and suspends His laws. Such arbitrariness in the order of nature would make natural science impossible. Indeed, the very idea of nature as the stable order of the universe would be denied by the thought that everything is the momentary product of God's arbitrary will.

Plantinga's response is to argue that natural science requires methodological naturalism, but not metaphysical naturalism. Metaphysical naturalism denies that there is any divine reality beyond nature, and that's the naturalism that renders evolutionary science self-defeating. But methodological naturalism is the assumption that we can explain everything in purely natural terms without invoking anything supernatural. The theist can accept this, because the theist assumes that God has created the order of nature and that He will not interrupt that order arbitrarily. Although miracles are possible, the natural scientist does not normally have to be open to miraculous events in the practice of science. This combination of methodological naturalism and theistic belief in the miraculous power of God is what Plantinga calls "Augustinian science"--the sort of science that Augustine would endorse.

While I agree that theism and evolution can be compatible, I don't agree that theism is absolutely necessary for evolutionary science, because I don't agree that combining Darwinism with metaphysical naturalism creates an incoherent position.

The weak link in Plantinga's argument for metaphysical naturalism as self-defeating is step 2, where he assumes that adaptive behavior is completely unrelated to true belief. The evidence of evolutionary history suggests that evolution produces cognitive faculties that are reliable but fallible. The mental abilities of animals, including human beings, are fallible because evolution produces adaptations that are good enough but not perfect, and this results in the mental fallibility that is familiar to us.

But despite this fallibility, the mental faculties cannot be absolutely unreliable. Even Plantinga concedes (in his debate with Dennett) that in the evolution of animals, "adaptive behavior requires accurate indicators" (70). So, for example, a frog must have sensory equipment that allows him to accurately detect flies so that he can catch them with his tongue. Similarly, the immune system of the human body must accurately indicate the presence of foreign bodies and then accurately devise responses to destroy the invaders. But then Plantinga argues that these accurate indicators don't require true beliefs. It's not clear that the frog has any beliefs. And the human being is probably not even aware of what the immune system is doing exactly.

What this shows, of course, is that much of an animal's adaptive behavior through mental activity does not require conscious reasoning at all. But for those animals who do develop some capacity for conscious reasoning--and most preeminently human beings--the accuracy of this conscious reasoning will be important for adaptation. As Evan Fales argues in response to Plantinga, the highest mental capacities of human beings are so biologically expensive in terms of the investment of energy they consume that it is implausible that evolution would have produced them unless they improved the ability of human beings to track the truth about themselves and their environment. Again, this is going to be fallible, but it's implausible that human beings could be naturally evolved for being in a state of complete and perpetual delusion.

And yet that's exactly what Plantinga asks us to imagine--that we could have been naturally evolved for a state of complete and perpetual delusion. Having taken this step of radical Cartesian skepticism, he then tells us that the only escape from such skepticism is to assume that God would never allow this to happen. But as always is the case for the Cartesian skeptic, this all depends on imagining scenarios that are utterly implausible and unsupported by even a shred of evidence.

Only those who find Cartesian skepticism plausible will find Plantinga's argument plausible.  Indeed, Plantinga's argument originated with Descartes.

For example, consider this possibility for human evolution suggested by Plantinga:

So suppose Paul is a prehistoric hominid; a hungry tiger approaches. Fleeing is perhaps the most appropriate behavior: . . . this behavior could be produced by a large number of different belief-desire pairs. . . .

Perhaps Paul very much likes the idea of being eaten, but when he sees a tiger, always runs off looking for a better prospect, because he thinks it unlikely that the tiger he sees will eat him. This will get his body parts in the right place so far as survival is concerned, without involving much by way of true belief. . . . Or perhaps he thinks the tiger is a large, friendly, cuddly pussycat and wants to pet it, but he also believes that the best way to pet it is to run away from it. . . . or perhaps he thinks the tiger is a regularly recurring illusion, and, hoping to keep his weight down, has formed the resolution to run a mile at top speed whenever presented with such an illusion; or perhaps he thinks he is about to take part in a sixteen-hundred-meter race, wants to win, and believes the appearance of the tiger is the starting signal; or perhaps . . . . Clearly there are any number of belief-cum-desire systems that equally fit a given bit of behavior.

Well, yes, these weird stories are all logically possible, as the philosophers like to say. But they are also utterly implausible, because there is no evidence that anything like this could have happened in human evolution. Plantinga's claim that there is no clear connection between adaptive behavior and true beliefs in evolutionary history depends on fantasies of his imagination unsupported by evidence. He has to do that, because if he actually looked at the evidence of human evolutionary history bearing upon the emergence of human mental faculties, he would be faced with evidence for the evolution of human cognitive capacities for exploring the world that are generally reliable, even if fallible.

He would also see evidence that human beings can use their fallible mental capacities to correct their mistakes. After all, the very capacity to recognize our fallibility presupposes our skill for reliable reasoning about ourselves and our world. There are good reasons to believe that this can be explained as an outcome of a natural evolutionary process in which divine intervention was not necessary.

Some related posts can be found here, here, here, and here.

One might also consider here the evidence that Michelangelo's Sistine Chapel's painting of "The Creation of Adam" reflects Michelangelo's knowledge of the neuroanatomy of the brain.

Does this support Plantinga's argument? Or does it suggest that what we see as the "image of God" in the human brain is a purely natural product?

Thomistic Nihilism, Greek Naturalism, and the Problem of Natural Right

The problem of natural right is the problem of whether nature has a intelligible order that can be known by human beings and followed as a guide for their lives.

Classic natural right such as one sees in the writings of Plato and Aristotle assumes that nature has an autonomous order of its own that can be known and followed by human beings.

Biblical religion assumes, however, that there is no autonomous order of nature, because nature is continually created ex nihilo by God, and thus at any moment, nature can collapse back into nothingness. Strictly speaking, then, nature as understood by the Socratic philosophers--nature as an enduring, self-contained, necessary order of being--does not exist from the view of Biblical religion.

Biblical religion thus creates the possibility of radical nihilism--the idea that nature depends on the mysterious, arbitrary power of God, and so there is no natural standard for human knowledge and action.

I have written about this contrast between Greek naturalism and Biblical nihilism in the chapters on Augustine and Nietzsche in Political Questions: Political Philosophy from Plato to Rawls.

This is, I think, Strauss's point when he says that the Bible has no idea of nature, and it is his worry about Biblical nihilism that motivates his criticism of Thomas Aquinas for making natural law too dependent on Biblical revelation.

I agree with Tom West that Strauss's critique of Aquinas is exaggerated. But I do think Strauss is correct in so far as Aquinas never fully escapes from Biblical nihilism.

As indications of Aquinas's nihilism, consider the following statements:

"Both reason and faith bind us to say that creatures are kept in being by God. . . . All creatures need to be preserved by God. for the being of every creature depends on God, so that not for a moment could it subsist, but would fall into nothingness were it not kept in being by the operation of the Divine power" (I, q. 104, a. 1).

"Some have held that God, in giving existence to creatures, acted from natural necessity. Were this true, God could not annihilate anything, since His nature cannot change. But . . . such an opinion is entirely false, and absolutely contrary to the Catholic faith, which confesses that God created things of His own free-will, according to Psalms 134:6--'Whatsoever the Lord pleased, He hath done.' Therefore that God gives existence to a creature depends on His will; nor does He preserve things in existence otherwise than by continually pouring out existence into them, as we have said. Therefore, just as before things existed, God was free not to give them existence, and not to make them; so after they have been made, He is free not to continue their existence; and thus they would cease to exist; and this would be to annihilate them" (I, q. 104, a. 3).

West tries to get around this theological nihilism through an interpretation of Aquinas's teaching on divine providence. West distinguishes three views of providence (67-68). The first view is that there is no divine providence. The second view is that God's providential power is so great and so arbitrary that there is no natural order at all. The third view is that God's providence is manifest in the eternal and unchanging order of nature and in the sharing of providence with human beings who exercise providence through their intellect. The second view, West argues, is the view taken by the Islamic theologians like al-Ghazali who deny the possibility of a natural order of causality as a blasphemous denial of God's unconstrained power. The second view is also taken by modern political theologians like Carl Schmitt. The third view is Aquinas's, which thus escapes from the nihilism of the second view that Strauss attributes to the Bible.

I agree with West that Aquinas does try hard to adhere to the third view, especially in his account of natural law. But he can never completely escape from Biblical nihilism.

One can see this in those many places in his writing where Aquinas embraces a divine command theory of morality--that the good is whatever God happens to command at any moment. For example, Abraham was justified in faithfully obeying God's command to kill his son Isaac: "Abraham did not sin in being willing to slay his innocent son, because he obeyed God, although considered in itself it was contrary to right human reason" (II-II, q. 154, a. 2, ad 2). Normally, killing innocent people is murder and contrary to natural law. But at any moment God can rightly command murder, because there is no natural law independent of God's arbitrary power.

After examining examples like this of Aquinas's divine command teaching, West explains: "Aquinas thereby draws attention to the unavoidable potential or actual conflict between the commandments of God who acts or seems to act outside the natural order (assuming that God is such a being) and the dictates of human reason. . . . Aquinas enables us to see that there is a choice to be made, theologically, between a willful, mysterious, and ultimately irrational God and a God who always acts in accord with the eternal law of reason" (77).

West leaves us wondering why Aquinas does not always make a clear choice in favor of "a God who always acts in accord with the eternal law of reason." The answer, I think, is that Aquinas cannot make this choice without openly denying Biblical religion.

For me, this is a big issue, because one of the most common objections to my argument for Darwinian natural right is that it fails to recognize that evolved human nature by itself cannot be the ground of moral judgment, because the ultimate ground is God's moral law as the command of his will.

Unfortunately, the proponents of divine-command reasoning fail to see the necessary implication of this teaching, which is nihilism.

Darwinian natural right is the alternative to such nihilism.

Some related posts can be found here, here, and here.