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Friday, July 12, 2013

A Critical Review of Ian A. McFarland's In Adam's Fall: A Meditation on the Christian Doctrine of Original Sin, Part 4. A better account of human desire.

For the fourth post in this series we will begin an examination in some detail Dr. McFarland's concept of "desire" and how it relates to the "will." The previous posts can be found here, here, and here. At several points in the book McFarland advocates for the proposition that "the will follows desire." In the last post I pointed out that "will" is an analytically useless concept; while the same cannot be said of "desire," I will argue that McFarland fails to make important distinctions between types of desires and how they interact with conscious processes. As a result, he draws incorrect conclusions about how the human personality works. Furthermore, McFarland worded the proposition to avoid two alternatives he regards as errors. First, he rejects the "Pelagian" concept of the "will" as a control center in human consciousness. The "will" simply acts according to a given desire. Second, he rejects the position of many non-Christian compatibilists and hard determinists that human decisions can be fully explained by any combination of "non-personal" causes, such as the state of brain chemistry, sensory input, and other environmental conditions. The will "follows" desire, but it is not "caused" to move in a particular direction in the sense that would entail that God created human beings such that they would be caused to sin. I will argue that he is at least partly wrong about a "control center" function of consciousness and completely wrong about human choices being uncaused by non-personal forces. This is an ambitious counter-program and will take at least a couple of posts to complete. Fasten your seat belts!

In the end, McFarland and I agree on a couple of fundamental points: All human action is motivated and for the most part we do not have a say in what motivates us. Our basic disagreement lies in the implications of these points for human responsibility, which I will address in a future post. In order to build my case against McFarland's account of responsibility, it will be necessary to lay out a better account of the role of "desire" in human decision-making. Some of what I will argue here summarizes points made by William Irvine in On Desire: Why We Want What We Want. For much of the rest I am relying on arguments and evidence presented by Robert Wright in The Moral Animal: Why We Are, the Way We Are: The New Science of Evolutionary Psychology, Steven Pinker in How the Mind Works, and E. O. Wilson in Consilience: The Unity of Knowledge. Don't expect page references. I'm too lazy and pressed for time right now to provide chapter and verse. Besides, every one of these books is worth a complete read. Alright, enough excuses for myself.

My first objection to McFarland's presentation of "desire" is that, while he wants to deal with desire "broadly-conceived" he nevertheless excludes a specific class of desires. As an example, consider what he says here:

For a sweating person to say he does not want to sweat is in this sense analogous to an alcoholic who falls off the wagon saying he does not want to drink: neither event would take place unless there was an underlying desire, and the expression "not wanting" is simply a wish that the desire were not present. Certainly any talk of a nervous person "desiring" to sweat must include the recognition that such "desire" is very different even from the desire for a drink on the part of an alcoholic whose drinking is ruining his life (not to mention from a parent's desire for the well-being of her child); but to completely depersonalize such functions is to risk falling into an anthropological dualism, in which it is somehow more correct to say, This body is sweating," than "I am sweating." (p. 85)
He never explains why the "wish" not to sweat is not a desire, which leaves me to provide an explanation. If he admits that such "wishes" are real desires it threatens his thesis that "will" simply follows desire." It is odd, to say the least, that the automatic sweating response expresses a desire but the very conscious embarassment that may accompany sweating somehow doesn't express a desire! There is nothing wrong with McFarland's claim that the autonomic nervous system's reaction to indications that the body is overheating expresses a desire, broadly-conceived. He errs in refusing to use that language for desires that go unfulfilled either because someone can't counteract opposing, unconscious desires or because she chooses to let the desire go unfulfilled. McFarland's problem is made even more obvious by the way he describes the opposite situation, in which a person's conscious decision processes determine to frustrate a specific desire:
The idea of the impotence of the will to free itself from sin should not be read in terms of a psychological description of the dynamics of temptation, as though the affirmation of original sin were an empirical statement about the ability of the will to engage in or refrain from a particular behavior [emphasis mine] (e.g., an alcoholic's ability to stay on the wagon). To confess the reality of original sin is not to claim that people cannot resist giving in to particular impulses [emphasis mine] (which they quite evidently can), but rather to reject the conceptual reduction of sin to the choice of evil over good.
McFarland's claim that the affirmation of original sin is not an empirical statement raises some problems that I hope to address in a later post. Notice how the alcoholic's desire to drink in the first quote has been suddenly transformed into a "behavior" or an "impulse" in the second quote. Why the different language? Because when a person successfully resists an impulse she is following a desire. Since McFarland's position is that the will follows desire and if there are conflicting desires it appears to make the will an independent arbiter between desires (and hence cut free from an intelligible account of human actions), one must deny that humans really ever have conflicting desires. McFarland never explicitly denies that humans have conflicting desires, but he does render a rather odd diagnosis of the "divided will" that underscores my point:
The problem -- the point of existential crisis that undergirds Augustine's analysis -- is that human beings can't want what they want. It is this incapacity that is the source of the experience of the divided will: we do what we desire, invariably -- but what we desire remains beyond our control. (p 75)
Yet it is a common human perception that "you can't always get what you want" and one of the reasons you can't is that you often have to choose between conflicting desires. It's not that you "wish" your desires were different; you don't have that wish at all. It's that you want to satisfy both desires and can't pull it off. One or the other will have to go unfulfilled. McFarland's theory leaves no room for this common human dilemma, and for that reason alone it is cruelly inhumane.

Underlying this misdiagnosis of the "divided will" is an oversimplified understanding of how human desiring works. According to most theorists, the brain acts like a fractious committee. The committee members represent various mental modules responsible for some facet of organismic function. Some of these modules are "stupid whiners" that, given the right sensory inputs, bombard some other set of brain circuits with requests to satisfy a given desire. In the committee analogy, these whiners harass their neighboring committee members or the chairperson with demands for more food, more drink, more sex, etc. The mental modules are constantly at work on sensory input from inside and outside the body, exchanging information with each other and with brain circuits that contribute to conscious thought and sending to other parts of the nervous system, including -- sometimes -- consciousness the results of their processing. Some of the results produced by "whiner" modules end up in control centers that process the results through a decision tree and send instructions to other parts of the body about an action to take in order to satisfy the "whiners." The activity stimulated by these control centers produces new input for the "whiner" modules that either dampens or inflames their demands. Some of these control centers are not in consciousness; others are. The unconscious control centers are like an independently-minded subcommittee that decides to take action without the knowledge or consent of the committee as a whole, and if they bother to report their decision to the committee at all, they do so after the decision has been taken. In many cases the committee as a whole only finds out about it after the consequences of the decision come in. At the conscious level, where our experiences are relatively integrated, surprising, unexpected, and unwelcome interruptions from these "whiners" can break into awareness, interrupting the flow of our thoughts, rearranging our sensory perceptions, and raising or lowering our emotions. It is currently a matter of controversy as to whether our conscious minds ever really "make" a reasoned decision about the demands of the "whiners." Many theorists believe that our decisions are delivered to consciousness whole by unconscious control centers and our conscious thought processes simply come up with rationalizations for a decision already made for reasons unknown. Personally, I doubt this is always true and submit the development of modern science as a counter-example. There is no reason to suppose that any unconscious control center shaped by natural selection would prefer humans to study quarks and the history of life over the study of how to produce more offspring. Nevertheless, it has been demonstrated experimentally that sometimes people who have no idea why they are motivated to take a particular action will, in the absence of an identifiable reason, invent totally false explanations. I hope to expand on this point in the upcoming post on responsibility.

For our present purposes it is sufficient to notice that several mental modules may be stimulating other parts of the brain to satisfy desires at the same time. Consider all the functions performed simultaneously by the autonomic nervous system, such as regulating breathing, heartbeat, and body temperature. Since each of these feedback systems operates at least partly independently of the others, that makes for three separate "desires" the human person is satisfying at one time. McFarland does not discuss the idea of simultaneous, harmonious desires, but I see no reason why he could not have incorporated them into his theory as it stands. Where his theory runs into trouble is in the case of conflicting simultaneous desires. Consider, for example, the case of an antelope approaching a drinking hole on the African savannah. The desire for water drives the antelope to the drinking hole, but before drinking the antelope carefully studies the surroundings for signs of a predator. A scent, the sound of movement in the grass, or the sight of a sudden movement will cause a panicked flight response and the antelope's desire for water will go unsatisfied for the time being. The flight response is instinctive in many species, human beings included. In other words, via natural selection many species' brains include prioritization functions which reorder desires based on predetermined criteria so that satisfaction of the desire most likely to promote the reproductive success of the animal gets the highest priority.

Irvine develops this idea in more detail in his book On Desire: Why We Want What We Want with the concept of a "biological incentive system." This incentive system is a result of natural selection's fine-tuning of the nervous system in many species to produce in the brains of individuals emotions that reward them when they act in ways that promote reproduction and punish them when they are in situations that threaten their ability to reproduce. This incentive system predates human beings by tens of millions of years at least. In mammals the flight response, for example, is accompanied by the fear emotion, in response to which the reflexive flight response is amplified by "intentional" movement to escape from danger or mount a defense. The incentive system also provides us with a ready-made framework for prioritizing desires. As a result, when we encounter situations in which multiple desires are clamoring for satisfaction but we are not able to satisfy them all at the same time, one or more control centers in the brain have prebuilt decision trees that help us prioritize the desires and attempt to satisfy the highest-priority desire first. Since this incentive system was built to promote reproductive success, not human happiness, in an environment far different from that in which most modern humans find themselves, it sometimes works against our long-term personal interests. Classic examples include disastrous male philandering and persistent overeating.

Clearly, then, our actions and decisions are all motivated. They are all aimed to fulfill a "desire." In that regard, admitting that we have conflicting desires and sometimes intentionally leave desires unfulfilled is no real threat to McFarland's claim that "will follows desire." Leaving aside for a moment our criticism of McFarland's use of the word "will," we must yet ask, "Which desire?" The process of natural selection, which shaped the biological incentive system, has as a final goal the maximized reproductive success of the individual possessing a given set of genes. In the end, it is the spread of the genes which measures success. Humans, however, are usually not consciously motivated by their success at spreading their genes. What moves them to action are emotions. In the end, what measures success is satisfaction, happiness, joy. Irvine calls these feelings "final desires." They are intrinsically motivating. In contrast, instrumental desires are desires for things that will satisfy final desires. Although our brains have been adapted to reward us with satisfying emotions when we perform acts that promote our ability to reproduce, that doesn't always work to our benefit. Sometimes we are driven to pursue counterproductive instrumental desires because in our ancestral environment getting these things yielded reproductive success and mutations that increased a sense of pleasure when obtaining those things yielded even more reproductive success. Maybe getting those things no longer increases reproductive success and so our sense of pleasure is dashed by bad consequences or maybe getting those things produces reproductive success at the cost of making us miserable because the environment has changed in some fundamental way.

"Virtuous" features of human nature, such as altruism, empathy, conscience, and even the sensus divinitatus have also been shaped by natural selection. Each of these characteristics has been calibrated in our long pre-history to reward our genes with increased reproductive success. There is debate about whether and/or which current cultural expressions of these characteristics are adaptations or by-products, especially in the case of the sensus divinitatus. At root, however, human "virtuous" desires arose by essentially the same processes as human "vicious" desires in the course of evolutionary history.

This brief account of the evolutionary origins of desire leads to a couple of observations about McFarland's arguments. First is the matter of control. McFarland asserts that we cannot help but "sin" even after conceding that humans can exercise some control over behaviors motivated by sinful desires, such as alcoholics abstaining from drinks. His thesis is that although human beings can exercise some control over their behaviors they have no way of controlling their desires. This is partially false. A classic case is addictions. Changes in the body's biochemistry brought about by the introduction of an addictive foreign substance can be reversed. Among these changes is the reduction or elimination of the craving response that occurs when the level of the foreign substance in the blood drops. These cravings certainly count as "desires" by McFarland's definition and in fact are final desires by Irvine's definition, since satisfying this type of desire is intrinsically motivating. On the other hand, changing final desires that are genetically-programmed is much more difficult. By the use of drugs and/or surgery it is possible to temporarily or even permanently suppress sexual desire. Other final desires, such as hunger or thirst, are at least as difficult to modify even temporarily. Instrumental desires springing from these, such as the desire to have sex with one particular individual tonight or a desire to drink a second cup of water after a morning jog are usually much easier to modify by various physical and/or mental operations. In our ongoing battle with our own maladjusted desires humans have been slowly but surely gaining more control over not only how our desires are expressed but the desires themselves. Nevertheless, these techniques do not change the fundamental structure of human desiring. In that sense, McFarland is correct that we are not in control of our desires. On the other hand, the discovery of the human genome is a potential game-changer. It is conceivable that at some point in the not too distant future humans will have learned enough about the human genome to introduce mutations that could stimulate the development of entirely new desires or the entire elimination of existing desires. Whether either of these outcomes is desirable or beneficial is beside the point.

Gaining increased control over human desires by itself does not necessarily threaten McFarland's conception of original sin. For one thing, all of these methods of controlling desire can be ascribed to the operation of God's grace. Human discoveries about the biological basis of human desiring and techniques that can be used to inflame or suppress desire would be consequences of God's common grace, according to traditional Reformed doctrine. Even the modification of the structure of human desiring via manipulations of the human genome and/or drug therapy in early development, for example, could be described as operations of God's common grace. In fact, everything good done by human beings who are not (yet) born again into the community of God's people is a consequence of God's common grace. This classical understanding of the relationship between God's grace and human "goodness" lies behind the assertion of Henri Blocher, whom McFarland mistakenly targets for criticism on this score, that humans sin when they can and as much as they can. Blocher's assessment assumes the operations of God's common grace in the lives of non-Christian sinners. Left completely to themselves, human beings would quickly devolve into utter wickedness. At every point it is God's gracious operations that restrain, resist, and channel human sinfulness and stimulate human virtue in the non-elect. It is by this means alone that we are not "as bad as we can be." McFarland's implied universalism could rule out the existence of a separate, "common" grace and classify all grace as "saving" grace. Regardless, McFarland would no doubt also ascribe any true human goodness exhibited by any human being whatsoever as a consequence of God's gracious operations, rather than some innate human power to pursue the good. On the other hand, I doubt very strongly that McFarland would be happy to classify genome manipulation or drug therapy as operations of God's grace.

The evolutionary shaping of human desires also leads me to ask some pointed questions about desiring God above all else. What kind of desire is this? What stimulates it? What brain structures are involved in its expression? What role does evolution play in producing it? McFarland attempts answers to none of these questions. It seems to me that he needs to.

I reserve discussion of desire and causation for the next post.

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