Spencer Caron ’20s
Unfortunately, my academic skill set does not naturally lie in the empirical sciences. No matter how much I enjoy reading about physics, and no matter how up-to-date I attempt to remain in regard to biological advances, it simply doesn’t transfer to mathematical and laboratory aptitude. So, though I can’t by and large explore the question, “Is all science just physics?” empirically, there exists no shortage of philosophers who are interested in this question from the theoretical angle. Basically, two major of schools of thought answer this question differently. On one hand, physicialists (sometimes called materialists) claim that psychology can be reduced to biological principles, biological principles to chemistry principles, and finally, chemistry to physics. For the physicialist, if we just knew enough about particle behavior, and our inchoate knowledge of quantum theory matured, we would be able to explain why Freud felt like he did when he listened to his favorite song, for instance. (It should be noted, not all empirical scientists are physicalists, though the general rule is that physicists are more likely than are psychologists to adopt such a physicalist view.)
On the other hand, there are numerous schools of thought that eschew such physicalist thinking. These schools are varied and debate amongst each other, but what they all hold in common is that not everything can be reductively explained by the laws of physics. A specific take on this issue by which I have recently found myself interested is the Emergent Theory within the field of philosophy of mind. Roughly, the theory holds that there are such things as “emergent properties” that cannot be accounted for through a mere examination of the physical components themselves. An example should help illuminate this view. Let’s assume that I am a recruiter for Holy Cross athletics. In this role, I would travel the country watching different players at their respective high schools. I would take careful notes of their height and weight, their specific skill set, etc. Upon arriving back at campus, I would present my notes to the coaching staff and make predictions about how these recruits would fit in within the players we currently had. However, I would not be able to tell for certain how the team would play with the new recruits until the first time they actually played together. That is, the team performance (often referred to as team chemistry) is an emergent property; even detailed knowledge of the parts, i.e., players, does not confer knowledge of the system, i.e., team.
Clearly, this hypothetical sports-team example is not necessarily the object of study of philosophers of science, but it gets the point of emergence across easily. Philosopher C.D Broad demonstrates the theory of emergence vis a vis chemical compounds. Specifically, in his essay, “Mechanism and Its Alternatives,” Broad points out that no amount of physical knowledge of the elements of nitrogen and hydrogen (their bond-structures, their reactivity, relation to other elements, etc.) would be sufficient for predicting the distinctive smell of ammonium; the smell of ammonium is the emergent property.
With the basics of emergence—just one antithetical view to physicalism—in mind, I’d like to apply emergence to the brain. I need not comment on all the incredible things that the brain can do, but I would like to focus on consciousness, specifically. That is, can we classify consciousness as an emergent property, thereby pushing back against the increasingly popular neuroscientific view that what we deem “free will” is subject to the same laws of physics to which, say, reflexes, are subject? If the physicalists are right, free will is nothing more than the linguistic label humans have applied to events that seem to have been “chosen” by the agent. In their view, there truly was not a choice; the neuronal firings reacted to a physical stimuli over which the human agent had no true control, and as such, the outcome could have been predicted had all of the neuronal information been made priorly available. Emergent philosophers of mind hold that, on the one hand, conscious decision making relies on physical processes, but, on the other hand, consciousness is an emergent property that simply could not have been predicted on the basis of physical laws. In other words, knowing about neuronal action potentials, the layered organization of the brain, etc. still would not confer knowledge of human decision making.
In plain terms, emergence states that the whole is greater—perhaps more accurately, different—than the sum of its parts. When the 80-odd billion neurons and glial cells arrange themselves inside of the human skull, the resulting “output” is something not reducible to physical laws. Thought for the overwhelming majority of history “common sense,” religiosity, or some combination of the two have held that what it is to be human goes beyond the physical. Though I am sympathetic with those who conclude that something like consciousness is not reducible to the firing of billions of neurons because this sounds as incomprehensible as the notion that “space extends infinitely,” this amazement doesn’t double time as an antithesis to physicalist. But, after reading Broad’s essay and other works speaking to the possibility that perhaps a wholesale acceptance of physicalism is premature, I am intrigued by the philosophically rigorous challenge of what is widely accepted in certain fields; that it is only a matter of time that physics claims to be able to explain everything.