NIDA and Naturalism

This is a friendly critique of a recent statement on addiction by Alan Leshner, director of the National Institute on Drug Abuse (NIDA).  Leshner is 90 percent of the way to understanding addiction naturalistically, but the remaining 10 percent is crucial.  Clarifying our concepts about agency is as important as assessing scientific evidence about the causes of addiction.  Without a clear notion of our place in nature, we will likely ignore or downplay evidence of precisely how our behavior arises from our environmental and genetic situation.

In a recent column in the National Institute on Drug Abuse’s (NIDA) monthly newsletter (V 16, #2), NIDA director Alan Leshner gets close to an entirely naturalistic view of drug abuse. That is, with minor but telling exceptions (which I will discuss), he sees drug abuse as a function of various causes, not a matter of willful misconduct. I’ll quote several paragraphs, emphasizing one sentence. He says that

… [A]ddiction encompasses both voluntary and compulsive behaviors. A person makes a voluntary decision to use a drug, and continues to use it until the repeated drug exposures change the brain's structure and functioning. As a result of these changes, the individual's scope for voluntary acts becomes severely restricted, particularly with respect to drug use. He or she now exhibits the essential features of addiction - compulsive, nearly irresistible drug craving, seeking, and use.

In fact, it even oversimplifies the facts to say that drug abuse is voluntary at first and subsequently becomes involuntary. There are voluntary and involuntary components to every stage of the process that leads from the initial decision to take a drug through addiction and treatment to abstinence. We know, for example, that many factors that people cannot control can either increase or decrease their likelihood of making the initial voluntary decision to use drugs. They include the quality of parenting one receives and whether or not one has undiagnosed or untreated mental illness or is exposed to a good prevention program.

The point that voluntary decisions, external influences, and brain changes all contribute to drug addiction is not just interesting theory. It has vitally practical implications.

Leshner sees that the voluntary component of drug taking is influenced by "factors that people cannot control." He quite properly places voluntary acts within a larger explanatory context, so that it becomes less of a mystery why the initial choice to use alcohol, nicotine and other addictive drugs gets made in some circumstances but not in others.

The question arises, however, as to whether there is any aspect of the voluntary choice to use drugs that isn’t ultimately traceable to factors outside a person’s control. Some factors influencing my choice to use drugs may seem at first glance well within my control, such as who I hang around with, where I go after school, and how seriously I take getting ahead in life. For example, no one is forcing me to consort with the neighborhood drug dealer; it’s just that he’s a cool guy and seems to have a lot of money and girlfriends. If I didn’t want to hang out with him, I wouldn’t have to, but since I do, I do. Being "within my control," then, means that I could refrain from the behavior in question if I wanted to refrain from it. Those with obsessive-compulsive disorder don’t have control over their repetitive hand-washing: as much as they’d like to stop, they pretty much can’t.

But what about my desire to hang out with the drug dealer? Is that within my control? That is, could I refrain from having this desire if I wanted to? Suppose I have some nagging thought in the back of my head that says "Mom said not to hang around with those guys. You’ll be a fool if you do." This bit of nagging surely acts as a motive not to have the desire to hang out with the dealer, or at least a motive to ignore its prompting.

But is it motive enough? Does Mom’s forecast of a bad outcome deter me? The answer to this question lies, clearly, in the relative strength of my attraction to the dealer compared to my inclination to listen to Mom. My behavior is the outcome of this contest of motives, and in the case we’re imagining it turns out that Mom’s injunction loses: I find that I’m hanging out with the dealer, the nagging quieted to an occasional whisper of regret. In other circumstances, or for someone else, it might have gone the other way.

But couldn’t I have exerted an act of will to quell the bad impulse, or amplify the good? Isn’t the outcome of these contests ultimately within my control? Here we reach the heart of the issue, for on a naturalistic understanding of the self, there is no internal, supervisory agent that exists apart from the confluence of motives. I have, perhaps, the rational capacity to anticipate what the outcomes will be if I act one way or the other, and such considerations might end up damping or amplifying one or both motives. But again, there is no agent that independently decides to conduct such deliberations – it either happens or it doesn’t, depending on what sort of person I am or the mood I’m in at the time (or, importantly, the state of my frontal cortex; see the NIDA research on how drug use can affect decision-making capacities at Further, there is no guarantee that rationality will make the good side win out, since nefarious behavior might lead to some pretty attractive outcomes. But this is somewhat tangential to my main point, which is that any agent that existed independently of desire would have no motive to act on either side of the issue, and so would be useless as a controller. Therefore, contests between motives have to work themselves out on their own, in their social and psychological context.

The upshot, from a naturalistic perspective, is that I don’t ultimately choose or control my desires, rather they partially constitute me as a person. This means that even though whether or not I hang out with the drug dealer is within my control (I could refrain from hanging out with him if I wanted to refrain) the desire is not: if a desire is powerful enough, I can’t simply refrain from having it, even if a countervailing motive makes me not want to have it. And I can’t simply choose my desires or their strength ex nihilo, since after all, such choices depend on motives I already have.

What this shows is that voluntary behavior is a function of motives of individuals that they don’t control. But then what does control these motives? What ultimately accounts for voluntary behavior, and more specifically, for the voluntary behavior leading to drug abuse?

The answer lies in the multiple factors, both remote and immediate, which shape a person’s character and desires (and therefore their motives), including the factors Leshner mentions: "the quality of parenting one receives and whether or not one has undiagnosed or untreated mental illness or is exposed to a good prevention program." There are of course dozens or hundreds of other such factors, depending on how you count them, and they include all the environmental influences a person is exposed to growing up, the endogenous, genetic influences which interact with the environment to create an individual, and the current situation in which the addict finds herself.

The crucial fact to keep in mind is that under naturalism there is no third thing, nothing that shapes a person’s character and motives that isn’t found either in the environment (physical, social, familial, peer) or in her genetic endowment. So the voluntary component of drug abuse, just as much as the involuntary, derives entirely from influences that created and currently affect the person. It isn’t a matter of free will.

At one point, Leshner writes as if there were such a thing as a person’s autonomous will, something that they could rally to the cause of beating addiction (if only they wanted to!): "The patient, for his or her part, must focus all the resolve and determination he or she can muster to stick with the treatment regimen and maintain abstinence." Let us imagine a patient, skilled in introspection, who is trying to muster resolve while under observation by a cagey therapist:

Therapist: How’s it going?

Patient: Well, I’m mustering my resolve the best that I can, but it seems like my desire to maintain abstinence is about the same as it was 10 minutes ago.

Therapist: Are you really focusing and mustering as hard as you can?

Patient: Yes, really, I’m trying, but my determination and resolve don’t seem to be increasing. I must be doing something wrong. Maybe I’m just defective in the willing department, sorry.

Therapist: Actually, it’s OK. Despite what some people think, this isn’t something you can really do on your own. What if I told you that if you stay clean for a week, then you’ll get grounds privileges? Feel any change in your resolve now?

Patient: Mmmm…wait, wait….yes, as a matter of fact, it seems like there’s more resolve than there was a minute ago. You mean, I’d actually get to see what’s off my floor?

Therapist: Right, but remember, you’ve got to stay clean. And by the way, there’s nothing wrong with your will. It’s just not something you can will, if you see what I mean.

Patient: Yeah, I think maybe I see what you mean. Doc, you’re a little weird, but you’re OK.

Therapist: No problem. See you in a week – clean!

On a non-naturalistic or what might be called a supernaturalistic understanding of the self, the patient could have bootstrapped himself into greater resolve without help from the therapist or any outside intervention. According to this view, (what is sometimes called the libertarian view of free will) there exists a freely willing agent within the person that could have chosen desires and motives in some crucial respect independently of any influence. Such an agent is above, or outside nature by virtue of being causally privileged: it causes without being entirely caused in turn. In explaining addiction, this means that the voluntary choice to start using drugs (or to stop using them) is ultimately attributable to the person alone. So drug use, at least to some extent, is beyond social or environmental control, with the user finally to blame for the choice.

The policy implications of the naturalistic and supernaturalistic views of addiction could not be more different. Under naturalism, even the first voluntary steps toward drug abuse are understood scientifically, that is, as a matter of contextual cause and effect. Such understanding points the way toward various interventions to prevent and treat addiction, and the drug user’s motives are seen to lie within potential control of policy. As much as we might find the addict’s conduct reprehensible, knowing that it arises entirely from a wider context keeps punitive attitudes in check and encourages compassion, since there but for the vagaries of life go we. Interventions will therefore emphasize attention to the economic, social, and physical factors that cause drug abuse instead of after-the-fact sanctions, while encouraging responsible behavior from addicts via incentives, not punishment.

Under supernaturalism, the person is thought to be self-originating in some respect, and therefore drug use is chalked up to free will, not anything we can control. This encourages a laissez-faire, devil-take-the-hindmost stance, since if it’s the individual’s ultimately free choice whether or not to try drugs, why bother to intervene? And of course punitive attitudes are given free rein, since the addict could have done otherwise in the environmental and genetic situation she found herself when drug use became an option. That is, she could have chosen not to have the desires she had; she could have willed herself, somehow, to be other than she actually was. For the failure not to have done so she deserves our scorn, and social sanctions, not prevention, are indicated.

Given these policy differences, the choice between a naturalistic understanding of addiction - the true view from a scientific perspective - and a supernaturalist understanding is hardly an academic matter. The conceptual analysis conducted above may seem academic, but it isn’t; rather it’s essential in order to clarify our thinking on fundamental topics which underlie attitudes and values. Failure to think through and make explicit our assumptions about self and agency is just as much an omission as to ignore empirical evidence.

As for evidence, research into the determinants of voluntary behavior strongly challenges the supernaturalist consensus on the existence of the freely willing self. See, for instance Gene Heyman’s 1996 paper, "Resolving the contradictions of addiction," in Behavioral and Brain Sciences 19 (4): 561-610, at, and his chapter "Is addiction a chronic relapsing disease? Relapse rates, duration estimates, and a theory of addiction," in Drug Addiction and Drug Policy: The Struggle to Control Dependence, Philip Heymann and William Brownsberger, eds., Harvard University Press, 2001. Heyman shows that the voluntary behavior involved in drug use is just as determined, albeit in different ways, as involuntary behavior. Furthermore, it seems as if the neural basis for cognitive functions involved in decision-making may be susceptible to change via exposure to drugs (again, see the NIDA research described at

In his column, Leshner is 90 percent of the way to a entirely naturalistic understanding of drug abuse and addiction. The above analysis is meant to fill in the remaining 10 percent so that no residual superstitions about the self remain to distort social policy on drug abuse. Since free will is widely thought too precious an assumption to challenge, it’s unlikely that explicit naturalism will find a home at NIDA (or anywhere else, for that matter) for decades to come. Nevertheless, the seeds of a new view of ourselves are being sown in the scientific study of addiction.

TWC, July 2001

P.S. Those who think libertarian free will either exists or is a necessary fiction in running a culture are invited to visit the Free Will section.