Free will
There was an interesting interaction that occurred recently on a podcast called Faith and Freethought (FF). The host, Richard Spencer was discussing the book The God Part of the Brain with author Matthew Alper, when around 40 minutes into the show I found myself very suddenly challenged intellectually by an exchange they had. FF is an atheistic philosophy show and many of the discussions deal with semi-formal philosophy and theology (reflecting the background of the host). Some of the shows have theologians and skeptics battling it out, and others feature recently published authors on various topics of interest to atheists. Richard Spencer is quite an amazing host. He has a keen sense for asking the right questions and directing the discussion, yet somehow letting the guests say their peace with minimal interruption. He also has the perfect voice for radio, direct and clear.
Most of the time I find myself being the “choir†to which the show is “preaching.†I occasionally disagree with some topic or line of questioning, but can generally say I agree with the thrust of the show’s overall premise. Sometimes, there is a topic I don’t really understand having to do with very detailed theological nuance or Biblical scholarship. However, what I mainly like about the show is that it tries to ask hard questions and get solid, intellectually sound answers on topics of general interest to me.
However, in listening to the particular show above, there came a section where Richard Spencer (an atheist) stated glibly, in a fashion a little out of character, that he was surprised that any atheist could actually believe in free will. He and the guest, Matthew Alper, had a bonding moment where they both agreed on this point. In a semi-patronizing tone, Spencer cited a recent show where an atheist caller tried to — can you believe it — actually defend free will! How could any rational person possible defend such a position?! Matthew Alper then described in his own words why some atheists might believe in free will, but that it was misguided, explaining the “correct†position (his and Spencer’s presumably) in some detail. An explanation I found totally unsatisfactory and essentially too simplistic.
I couldn’t believe my ears and had to stop the show to collect my thoughts. Until that moment, I had assumed, probably for 20 years, that it was “obvious†free will existed and that all intelligent, educated, thinking people would clearly agree with this. People might disagree on the process or the neuroscience, but not in the general existence of free will. Only very misinformed people didn’t believe categorically in free will. In some sense, this was probably a healthy moment for me. Listening to shows of this sort can become a form of groupthink, and you become accustomed to agreeing with basically everything (frequently because you actually do), going against the very notions of freethought and atheism. But here was a person whose views I respected (Spencer) challenging a long held position of mine.
The basic foundation of Spencer and Alper’s position, which I completely agree with, is that atheism is rooted in naturalism (with a little “n”), a form of realism. That is, existence is rooted in real physical processes governed by nature. There is no supernatural element operating in the brain. In this same vein, the human mind, and thus consciousness, is generated by brain function which is in turn governed by the constraints of biology, chemistry, and physics etc. There is no “self†or “consciousness†or “soul†beyond the physical processes in the brain; it might be complicated, but you don’t need to add anything fundamentally new. Perfectly reasonable. No disagreement here.
But how they applied to free will diverges from my view. Spencer seemed to indicate that the existence of free will implies a god and a soul. Therefore, the notion must be discarded by atheists. In fact, he painted the idea of free will as a fundamentally religious idea and determinism as an atheistic, natural one! I honestly don’t understand why he has that position. I do find it ironic, however, that the name of the show is “Faith and Freethought,†yet Spencer does not apparently believe in free will, which in my mind is a close cousin to free thought. It made me feel like he was using some obscure “formal†definition of “Soul†and “Free Will,†which cast the argument along unfamiliar lines using familiar, colloquial language. This has happened from time to time on the show where formal philosophical or theological terms are used — and this kind of discussion quickly goes over my head, since I don’t know the jargon. Alper reinforced this view by saying how clear it was that we were governed by our circumstances. He seemed to be arguing that since we didn’t have control over EVERY aspect of our existence (where we were born, who we were born as, and many other constraints in our lives), then we “clearly†can’t have free will. That’s why I think we must be using some formal definition of free will and talking past each other. I would simply say that we have free will within the constraints of our circumstances. Some things we can control, and some we can’t. But the very existence of ANY choice embedded in our life is evidence for free will. Having infinite choice is not a necessary condition for free will. But I think perhaps in formal philosophy, the discussion of free will may be an either-or sort of question, not a practical or physiological one, and that free will (the ability to make choices, create opportunity, and demonstrate personal volition) either occurs in a state of absolute freedom or not at all. I would call this a straw man or naive logical definition of free will because it is trivial, if that is indeed what they mean. In this sense, it IS obvious we don’t have free will. I can’t change the day of my birth, my skin color, or my height at will. There are lots of things in the universe out of my direct control. But within the constraints of my circumstances, there are many things I can control. Choices made by internal volition in daily life is obviously, to me, anyway, a very real thing.
The next issue is determinism. Their implicit reasoning here seemed so odd, but was unspoken, so I wasn’t sure I was understanding them correctly. Here, they were acting like greek philosophers pondering natural law through pure logic alone. Something, as a physicist, I know you cannot easily do responsibly. Sure, its cute, but it really gets you nowhere in determining how the world really works unless you can make statements that support and predict experiments. For example, without a real microscopic understanding of consciousness, you can’t say anything definitive about free will. Their argument, was something like:
1) Determinism removes free will;
2) Natural law is, by definition, deterministic;
3) Since the brain is made of materials (molecules, atoms, electrons, etc.) that obey interactions governed by natural law, the brain must also be deterministic in function;
4) Since brain function determines consciousness, mind, thought, choice, experience, memory, etc., are all deterministic;
5) Free will does not exists; QED
The logic flow is fine, but let’s examine the argument line by line.
I would argue that the first premise is a fair assertion, but not necessarily a given. It presents a worthwhile question to explore empirically: does determinism remove free will? From a physical point of view, is it scale dependent? For example, I would agree that macroscopic determinism would pretty much imply a lack of free will because all macro systems would be simply following an algorithm. But for me, in terms of the questions posed here, I think the question is: does microscopic determinism (where physical law makes its claims in this biological context) imply macroscopic (behavioral) determinism? One might invoke the old “classical hidden variables†ideas. If we have a microscopic theory that is totally deterministic, then macro determinism follows “in principle,†even if we can’t necessarily see or use it realistically. It might look random or free, but the randomness and freedom is fake in an absolute sense. That is, if you could track the microscopic classical behavior of every particle in the universe, and know all the interactions exactly, then the unshakable determinism of the macro world would would fall out as a byproduct. First, I have to say that that kind of thinking is “so 19th century†even if there is some validity to the reasoning (e.g. statistical mechanics or microscopic computer models leads to ideal gas law behavior). However, modern studies into determinism in classical non-linear systems has given some surprising results. Systems that are, in principle, totally deterministic can display what are called “emergent phenomena.†Chaos theory and complexity theory contain such examples, but even in more everyday processes like phase transitions are also in this category. It isn’t clear to me that these processes are “deterministic†in the usual way one usually uses the term. I have a hunch that consciousness is basically going to fall into this category of emergent phenomena. You hit a certain neuron density combined with a certain class of brain operations and stimuli, and the thing we call consciousness emerges from this system like ice from liquid water. Saying the brain is deterministic and thus lacks free will is like naively calling the internet “a series of tubes.†Calling it that misses the essential elements of highly non-linear interacting sets of complex information systems that can provide states of activity you would never observe if you just blindly connected some tubes together. Another example might be a detailed deterministic prediction of a lightning strike. We understand the microscopic physics of lightning exactly (static discharge in air) and can make general statements about where and when it will strike. We can even control where it strikes to some degree by providing elevated ground points and so on. But it isn’t clear to me that the exact shape, time, duration, energy, charge, discharge, and touchtown points could be predicted for a given strike even in principle in a hypothetical universe where we had information about everything. My guess is that it is a kind of emergent phenomenon that represents the “classical randomness†I was discussing.
Another interesting point is that even when working on the solutions to the very simplest apparently deterministic, classical systems, the complete determinism frequently needs to be imposed from without. An example is sliding a ball off a cliff of a certain height at a certain speed in the absence of air resistance or friction. Treated as a point object, this is the perhaps the simplest sort of mechanics problem to solve in high school physics. Once launched, you know all the external forces acting on the ball and a simple application of Newton’s second law will give you a complete solution to any question you would want to know about the ball such as where it lands, how long it takes to hit the ground (no bouncing), etc. But if you solve for the time, you discover that you actually get TWO answers, only one for the relevant system of interest. That is, the physics is really solving two problems at the same time and you, as the user, must actively select the right one based on the setup of the problem. Obviously nature does not really take square roots and get two solutions. That’s just a byproduct of our modeling. Nature just does what it does and the algorithm we project it onto (Newton’s laws and the corresponding mathematics, developed from observation of patterns of consistency in nature) is just a representation of nature. But it goes to show that you can’t make the category error and confuse the representation of nature with nature itself. A law of physics is not nature. Nature does not follow laws of physics, laws of physics provide consistent algorithmic mathematical frameworks and representations which model nature. Just because our theory is deterministic and, given the initial conditions, we can calculate the location of the ball at every instant for all time, does not mean that’s how nature does it or that nature is deterministic. It just means that our law or model is deterministic and is a good representation of nature given the assumptions we used. We are, in some sense, projecting nature onto an algorithmic, deterministic basis because that’s what we can actually calculate. In the context of free will, it forces us to ask if determinism in a physical theory of nature necessarily implies nature itself is deterministic and thus destroys free will.
The second assertion is just incorrect, so (3), (4), and (5) fall. Perhaps I’m misrepresenting the issue their application of natural law, but, as an empirical fact, natural law is not deterministic at its core. To the very best of our knowledge, quantum mechanics is a complete physical theory and is intrinsically probabilistic and non-local without hidden variables. It is the most accurate and fundamental representation of nature we have. All natural law at all scales, should, in principle, have a quantum origin. The universe only appears classical and deterministic on meso- and macro-scales because of decoherence (into pointer states) and entropy (but this is an active area of research). Now let me make it clear that I’m NOT claiming quantum theory necessarily plays a direct role in brain function any more than it does in the trajectory of the ball thrown off a cliff. So what is the role quantum mechanics plays in the brain? It is a legitimate question to ask, and should be explored, but I suspect that the warm wet environment of the brain is not going to support any quantum coherence at any useful biological scale (however, at Berkeley Lab, quantum mechanics was recently shown to play an important role in photosynthesis in plants! This is also a warm, wet environment, yet quantum mechanics seems to have a function there). My point is that if physics is an accurate representation of nature (an empirically supported statement), all physical processes, including both the brain, the ball, and indeed all macroscopic systems, MUST be able to be described in quantum terms at their fundamental levels. If you are a true adherent to naturalism and realism, given what we know about how the universe works, your basic premise of nature must START with quantum mechanics and thus the assertion that nature is inherently probabilistic (although, oddly, the *probabilities* are themselves deterministic — that is, evolve in a well defined, calculable fashion). The question then becomes not “how do we get randomness from a deterministic natural law†but rather “how does an apparently deterministic classical natural law at the meso- and macroscopic scale emerge from a fundamentally random microscopic theory.†If you don’t accept this and don’t believe in quantum mechanics, and only rely on the very limited classical physical law you are exposed to on human macroscopic scales, I clam you are probably not a realist nor an adherent of naturalism. Or, if you are, it is a toy form of naturalism that has not updated itself beyond 19th century tinker-toy and ping-pong ball models of matter and energy. Don’t get me wrong, these simple mechanical models of the universe can get you quite far in understanding the world at practical, everyday scales, but it isn’t a compete description of nature by a long shot.
The last point I would like to make rolls back the discussion a bit to a cruder scale. Forget about quantum mechanics, forget about emergent phenomenon, forget about category errors in mistaking the representation of nature for nature itself. Imagine that the natural world really is a set of unfolding algorithmic equations and is deterministic on all scales. From this reasoning, free will can’t exist. We live in a pre-arranged algorithm that is unfolding in such a way that we have no control over any scale of our existence. However, there still remains the unshakable perception of free will. That is, the sense every human has that free will exists and that our choices and actions can be made (within constraints of our circumstances) by our own internal volition. That is we live in a world where individual humans have behavior indistinguishable from what any reasonable person would call “free will within constraints.” In this model, we have “effective†free will. But how is this possible? Is this just an issue of hidden variables? We are simply not privy to all the gazillions of variables that are unrolling for every particle in the universe that affects every particle in our bodies at every instant, so something approximating free will appears? So even under this toy model of deterministic physics, one is still left having to explain why we have some property indistinguishable from free will in spite of a totally deterministic world.
So, the way I would respond to the issue of free will can be summarized as the following:
- By experience, we know that individuals possess something that appears to be free will within the constrains of their circumstances;
- Exactly how this occurs physically is unclear:
- some vastly complex, but ultimately totally pre-determined set of understood physical process give the “illusion†of free will because of hidden variables;
- some non-deterministic, probably complex, physical process still within known physics and chemistry, but not yet not understood in a neurological context;
- For example, a classical but chaotic non-linear or emergent process;
- Perhaps quantum mechanics plays a role, allowing for fundamental randomness:
- directly: some quantum process is at work like tunneling
- indirectly: smearing initial conditions in a chaotic one
- Even if quantum mechanics does not play a direct or indirect role in brain activity, QM is still the underlying physics for all physical processes.
- the question must be rephrased: why do we seem to see the illusion of classical determinism at any scale?
In short, we need a real microscopic physical understanding of the brain and how consciousness is created before we can address the issue of “real” free will, even if we perceive we have it. It is not something that can be resolved through pure reasoning alone, but through scientific investigation of brain function.