Joshua Greene Battles Dualism

Among the more vigorous advocates of progressive naturalism, although he doesn’t call it that, is Harvard neurophilosopher Joshua Greene. His experimental work using MRI scans of subjects engaged in moral decision-making strongly suggests that even the very highest human cognitive and moral functions are carried out solely by the brain; there’s nothing else there to do it, and the brain is up to the job. The conclusion that we are not of two natures, body and soul, is the gateway, he argues, to a more enlightened, humane view of ourselves.

Linked at his website are many articles worth reading, including his wonderfully titled doctoral dissertation, destined for publication as a book by Penguin Press. His paper with Jonathan Cohen, “For the law, neuroscience changes nothing, and everything,” has been widely cited in the growing literature on how neuroscience might impact the criminal justice system. It sets the progressive standard for what criminal law might look like should we someday accept a fully science-based, naturalistic understanding of ourselves. Conservatives content with the retributive and highly punitive status quo must now contend with his arguments, and his data.

Among recent additions at Greene’s homepage is a forthcoming book chapter, “Social Neuroscience and the Soul’s Last Stand,” in which he briefly describes a good deal of his research. He writes

…the soul will officially expire when the mechanics of the moral mind become transparent. I believe that the death of the soul may prove to be one of psychology and neuroscience’s most lasting contributions.

It’s seeing the “clockwork” of the brain in vivid detail that might eventually cement the death of the soul, although committed dualists can always insist there’s something more science can’t see. But that aside, why is it so important to really know, in our gut, that we don’t have such a thing? Isn’t that the most dispiriting conclusion we could possibly reach, figuratively and literally?

There’s no question that for many the death of the soul is unthinkable, or if thought, rejected immediately. There’s simply too much at stake: life after death, the special dignity of not being “merely” material, the soul’s contra-causal, determinism-defying freedom, among other invaluables. As one concerned dualist said recently (personal correspondence) “No matter how you parse it, determinism requires that we regard ourselves as things rather than as subjects.” Without the soul, perhaps, we become mere things. Responding to such concerns is one responsibility of those advocating naturalism, for instance see here and Appendix A of Encountering Naturalism.

But as Greene points out, whatever our discomforts might be, belief in the soul does a lot of damage, so if it’s false we should give it up. It helps to motivate religious conflict, regressive anti-choice abortion policies, opposition to stem cell research, complacency about environmental problems (since the life to come is what really matters), moralistic attitudes about mental illness, and a needlessly punitive and inefficient criminal justice system. On this last point he says

In the United States, at least, our prison system is very good at making people suffer, but its merits as a system for preventing future crime are highly questionable (Tonry, 2004). If we were more interested in reducing crime, and less interested in making guilty minds [that is, souls] suffer, we might all be better off.

All told, giving up the soul, if we can reconcile ourselves to it, would be an important contribution in achieving a more humane, sustainable culture. And this is why the intellectual and scientific battle against dualism is so worth fighting. In his conclusion, Greene says

Officially, we scientists already know that the operations of the mind are the operations of the brain, and not those of an immaterial soul. This is, at the very least, our working assumption. In making this assumption, however, we part ways with the rest of humanity, the vast majority of whom explicitly believe that we are souls housed in bodies. Such dualist tendencies are, in my opinion, a major social problem, and may become increasingly destructive. If that is correct, then dispelling dualism is serious business, at least as serious as curing cancer, and probably more so. If anything can cure us of our dualist tendencies, it is social neuroscience, the physical science of human experience. By decomposing the social brain into its mechanical components we can do good science in the conventional sense, but that is, I think, the least of what we’re doing. Social neuroscience is, above all else, the construction of a metaphysical mirror that will allow us to see ourselves for what we are and, perhaps, change our ways for the better.

Progressive naturalists and humanists can only agree, and wish Greene all luck and power in his challenge to dualism.

Unfounded Worries about "Neuro-Determinism"

Raymond Tallis, speaking for the Manifesto Club in London, presented a spirited sally against the threat of “neuro-determinism.” To his way of thinking, determinism robs us of the “Enlightenment faith that… a human being is ‘an independent point of departure’. Each person is a new beginning, able to contribute to shaping the future for good or ill. We are not fated to act out a pre-ordained script.” Tallis expresses a common worry that's surfacing more often as neuroscience reveals the material workings of even our highest capacities.

His arguments against neuro-determinism aren’t particularly compelling, but it’s interesting that he thinks that only by denying determinism can we remain optimistic and effective agents, genuinely committed to the improvement of mankind. He says “there has been a counter-Enlightenment denial of the centrality of individual consciousness in human affairs” coming out of recent humanities and sciences. It seems he confuses the likely true claim that human conscious processes are fully caused with the idea that such processes don’t really have effects of the sort which make us effective agents. That is, he conflates determinism with fatalism, a common error.

This is unfortunate since he must deny the findings of the sciences or downplay their significance in order to secure what he thinks is essential to have real power: having contra-causal free will. The irony is that the Center for Naturalism takes the position that we're far better served by seeing that we don’t and couldn’t have such power. After all, its attribution is often used to assign ultimate credit and blame in ways that justify punitive attitudes and practices, demonize enemies, and marginalize the unlucky in life. Further, positing the existence of contra-causal freedom necessarily leads to ineffective policies, since we ignore the actual causes of human behavior. So we don’t need to suppose we're free in this quasi-supernatural sense to have power and use it humanely, quite the opposite.

Curiously, as he goes along Tallis seems to accept the fact we are not causal exceptions to what he calls Laplacean, that is, deterministic nature. He says our freedom comes from having higher order capacities, personal and social, that distinguish us from simple mechanisms, plus the fact that we are proximately self-creating once we get past childhood. But all of this is consistent with the fact that higher-order capacities and proximate self-causation involve complex, recursive mechanisms, which don’t need to transcend Laplacean determinism to be causally effective. In any case, this just goes to show that the presumption that we have and must have contra-causal free will exists even among smart, critical thinkers, who only want the best for humankind. Another instance of smart (and very progressive) folks running off the cognitive rails is described in The Specter of Scientism.