Perhaps only scientists read essays published in the Proceedings of the National Academy of Sciences, but at times it contains commentary on topics of broad general interest. In a special "Inaugural Article" by a member of the National Academy, appearing on March 9th, 2010, we find a biologist discussing free will and the criminal justice system. What is discomfiting is not that a biologist should venture into such discourse, but rather his failure to examine the assumptions underlying his analysis and the category mistakes which follow from such failure.
In that “Inaugural Article,” Anthony Cashmore makes the astonishing claim that not only do human beings "have no more free will than a fly or a bacterium, in actuality we have no more free will than a bowl of sugar." As he remarks, "the laws of nature are uniform throughout, and these laws do not accommodate the concept of free will." Cashmore concludes that we ought not to base our criminal justice system on the illusion that human beings have free will and are, as result, in control of their behavior "in a manner that is something other than a reflection of their genetic makeup and their environmental history."
Cashmore recognizes the difficulties in moving from our present system of justice to one that recognizes that biology shows us that our behavior is exhaustively attributable to genes, environment, and chance. The latter refers to stochastic (i.e., random) processes that have their source in the "inherent uncertainty of the physical properties of matter."
The implications he draws for the law are clear: "I cannot be held responsible for my genes and my environment; similarly, I can hardly be held responsible for any stochastic processes that may influence my behavior!" He thinks we certainly should minimize the retributive features of criminal law, that is, features which are grounded in the "illusion" that we freely choose what we do. After all, as he says, we are only "mechanical forces of nature" that "by some mechanism" have "evolved the phenomenon of consciousness, which . . . has conferred upon us the illusion of responsibility." Despite his claims, it is not exactly clear how the law should treat "mechanical forces of nature."
Cashmore has little patience with Cartesian dualism and what he calls the "magic of the soul." Even though contemporary scientists have dispensed with the soul, he says, they have not taken the logical step of rejecting free will: this despite that fact that there are no "molecular details" concerning the "mechanism" of free will. Here we see Cashmore's commitment to the philosophical position of materialism (which he simply assumes to be identical with good science). Appeals to what are called "emergent properties" associated with neural networks, fail as accounts of free will, he thinks, because there is no mechanism (again identified with "free will") that affects the activities of atoms that is not explicable in terms of genes, environment, and chance. For Cashmore, there simply is no "causal component" which would account for free will. Of course, he limits his notion of cause to some material factor. All of this is the result of his a priori embrace of materialism.
Cashmore ignores recent developments in what has been called systems biology, which rejects reductionism (especially genetic reductionism) in accounts of living organisms and recognizes the influence of the whole (in this case the whole conceived as a complex system) on its component parts. To acknowledge the importance of what is called top-down causality does not deny the role of bottom-up causality. Such a holistic scientific account of living things is increasingly attractive to biologists, but it is ignored by Cashmore, who observes that "as living systems we are nothing more than a bag of chemicals." Organizing principles, what Aristotle would identify as forms, play little role in any exclusively materialist description of who we are. A "bag of chemicals" is nothing more than what Aristotle would call a heap, and thus would lack the unity essential for something to be alive and to perform activities characteristic of the living as living wholes. It is simply wrong, scientifically and philosophically, to consider a living being as only a bag of chemicals.
Cashmore sets the stage for his discussion by contrasting Cartesian dualism, which he identifies with vitalism, and modern scientific materialism. Since there is no evidence for the existence of a separate entity, a soul, the only rational option, so he claims, is to accept an exclusively materialist account of the nature of things. Belief in free will, he concludes, "is nothing less than a continuing belief in vitalism—a concept that we like to think we discarded well over 100 years ago!"
Religion does not escape his analysis. He claims that free will only makes "logical sense" as long as one has "the luxury of the 'causal magic' of religion. Neither religious beliefs, nor a belief in free will, comply with the laws of the physical world." Obviously, once one starts with the premise that there is nothing more than material stuff, claims that deny such a premise are rendered illogical.
Cashmore cites approvingly analyses of David Hume, Daniel Dennett, Susan Blackmore, and others to support his rejection of free will, but he assumes that there is no other choice than that between dualism/vitalism and materialism. The existence of a soul, of the immateriality of the human intellect, as well as the reality of free will, do not, however, require thinkers in the tradition of Aristotle and Thomas Aquinas to embrace the dualism which Cashmore finds unscientific and illusory. Based on philosophical distinctions between form and matter as the co-principles of all physical reality, it is surely possible to affirm that human freedom does not require a separate entity which thinks or chooses. Human beings as substantial unities—as wholes—think, choose, and act precisely as single entities. The distinct abilities they possess are manifested in thought and action. To understand human beings—or any natural thing (living or non-living)—in exclusively material terms is to ignore fundamental features of reality. On this very point contemporary systems biology offers ample support for the importance of considering whole entities precisely as wholes.
Among other things, materialism fails to account for the unity of the whole; for this we need some concept of form. Form (which in living things is the soul) is the principle of actuality of a thing; it makes the thing what it is. To dispense with either form or matter is to misunderstand what is real. Both form and matter are real causes; to ignore either is to fail to account for what we observe in nature. The form is a principle; it is real and is essential to make things be what they are, but it is not a separate entity. Form is not the effect of material causes; it is a cause in its own right.
Such an analysis takes nothing away from affirming that we are animals that think and choose, or that biology has much to tell us about who we are. Biology, however, needs richer notions of cause than that supplied by a materialist philosophy. In support of his argument, Cashmore cites, for example, developments in imaging techniques which allow "changes in neuronal activity to be correlated with thought processes." He thinks that such correlation will also enable us to see what we call free will as nothing other than a biochemical process. Ultimately, he seems to identify "to be correlated" with "to be caused." Surely, a more adequate reflection on "cause" in its many senses is called for.
Rather than provide here an extensive defense of what is called a hylomorphic (matter and form) approach to reality, I simply want to note that such a view is not a kind of vitalism or dualism. Whether it is true, of course, requires careful analysis; neither its truth, nor the purported truth of the materialism Cashmore affirms, should be accepted uncritically. What Cashmore sees as an uncontroversial scientific claim is in reality a philosophical judgment which needs to be examined in the proper discipline: the philosophy of nature.
Free will lacks any "causal component," therefore it is an illusion; so Cashmore boldly proclaims. As we have seen if we limit the notion of cause to material stuff we are not going to discover a "cause" of free will, even though we might find correlations between physical phenomena and conscious choice. But correlations are not causes.
That human beings are free agents in the world is a starting point for ethics and moral philosophy. As a starting point, such an affirmation is not a conclusion reached but, rather, a truth recognized as such. Disputes about free will may very well employ evidence from the natural sciences, but these disputes are dialectical, not demonstrative. Dialectical discourse helps to clear away, so to speak, obfuscations and other barriers to recognizing first principles. Geometry, for example, does not prove that there are points and lines; it argues to them dialectically. There is a kind of intellectual intuition at work here and all rational inquiry depends upon the priority of such intellectual seeing. Free will can neither be confirmed nor denied by appeals to some "molecular mechanism." Its existence is argued to (and defended, if necessary) in a wholly different order. To enter that realm of discourse, however, we would need to clear away any brambles of materialism, since a prior commitment to an exclusively material account of the real limits and obscures our vision. Even materialists can only defend their position by dialectical argumentation.
Cashmore is correct to see that ethics (in this instance, questions of law) needs to find support in our understanding of nature. If in fact free will is an illusion, we ought not to construct legal systems on the basis that there is free will. We need the best science has to offer in order to navigate effectively in this world. As Cashmore's essay reveals, despite his claims to the contrary, natural scientists need a robust philosophy of nature if they wish to make judgments beyond the realm of reporting empirical data. Such a philosophy of nature must address topics such as what it means to be a whole natural entity, what it means to be alive, as well as even broader questions about the nature of cause. The philosophy of nature is a more general science of nature than any one of the specific natural sciences, and it depends on these sciences for the evidence it uses in its own analysis. Reason needs to be our guide in the enterprise of examining the nature of things, but reason embraces far more than what the natural sciences alone tell us about the world. Notions of human responsibility and freedom are central to much of philosophy, and they are not successfully challenged by appeals to science. More often than not such putative challenges, as found in Cashmore's essay, find support in a materialism which is little more than a disguised scientism: the view, that is, that the nature of things is exhaustively (and exclusively) found in the empirical sciences. Such a belief is the real illusion.
William E. Carroll is Thomas Aquinas Fellow in Science and Religion at Blackfriars Hall and a member of the Faculty of Theology of the University of Oxford. He is author of Galileo: Science and Faith; La Creación y las Ciencias Naturales: Actualidad de Santo Tomás de Aquino, and co-author with Steven E. Baldner of Aquinas on Creation.