Undetermined - a response to Robert Sapolsky. Part 4 - Loosening the treaties of fate

In Part 3 of this series, I argued that organisms really do think about what to do, really do come to their reasons by reasoning, and really do make decisions, in ways that cannot be pre-determined.


If the neural computations are causally sensitive to semantic content, rather than detailed syntax, and those semantics relate to organism-level concepts, and all that information is integrated in a hugely contextually interdependent way, and is used to direct behavior over nested timescales, in ways that cannot be either algorithmically or physically pre-specified, based on criteria configured into the circuits derived from learning, which embody reasons of the organism and not any of its parts, then I would say that just is the organism – as an integrated self with continuity through time – deciding what to do.


I also argued that more fundamental principles of indeterminacy and emergence and organisation are the things that enable organisms themselves to come to be in charge of what happens



But what if the universe as a whole is deterministic?


How could mental states – or any states of the whole organism – have causal power over how the system evolves, when all the causes are supposedly located at the lowest levels? How can we escape from the confines of reductionism?


Sapolsky considers the question of physical pre-determinism at the lowest levels of reality and comes to a similar initial conclusion as I do, which is that the general consensus from physics is that the low-level laws of quantum mechanics are not deterministic:


For our purposes, the main points are that in the view of most of the savants, the subatomic universe works on a level that is fundamentally indeterministic on both an ontic and epistemic level. (page 213)


However, he argues that the law of large numbers means that any such random events at the level of individual molecules will be averaged out across the system and will thus not manifest at levels we care about. Oddly, one of his arguments for this is that the system in question is not deterministic at those higher levels:


People in this business view the brain not only as “noisy” in this sense but also as “warm” and “wet,” the messy sort of living environment that biases against quantum effects persisting. (page 221)


The argument thus seems to be that individual random events at low levels get washed out by higher-level randomness:


…quantum effects are washed away amid the decohering warm, wet noise of the brain as one scales up. (page 238)


It’s not clear where, in this picture, the higher-level randomness is supposed to come from, but actually, for the purposes of the discussion of free will, it’s sufficient that it exists. The important point is that physical pre-determinism does not hold, at any level. This means the evolution of the system through time should not be completely pre-determined, but open.


Sapolsky still maintains a hard reductionist stance, however, and while he engages with the concepts of non-linearity in complex systems, he fails to make a crucial connection. He writes that the reductionist tradition of only studying linear relationships in isolation:


…guaranteed the incorrect conclusion that the world is mostly about linear, additive predictability and nonlinear chaoticism was a weird anomaly that could mostly be ignored. Until it couldn’t be anymore, as it became clear that chaoticism lurked behind the most interesting complicated things. A cell, a brain, a person, a society, was more like the chaoticism of a cloud than the reductionism of a watch. (page 145)


However, based on the literature on chaotic systems, he concludes:


Even if chaoticism is unpredictable, it is still deterministic. (page 148)


Now, it is true that many of the classic examples of chaotic systems – or, more precisely, computer simulations of such systems – are deterministic. The evolution of such simulations can be extremely sensitive to slight changes in the values of different parameters at far decimal points, which can have unexpected, but consistent, influences over future states.


However, that does not mean that chaotic systems in the real world – outside of computer simulations – must also be deterministic. If there is some real indeterminacy in the physical parameters of a system (which we’ve established there must be), and it has the kind of complex, non-linear dynamics that make it chaotic, well then it will be genuinely unpredictable, not just in practice, but in principle. The parameters describing its future states just won’t have truth values in the present, beyond some decimal point. I argue in Free Agents that the universe as a whole is like that. It operates a kind of just-in-time reality, where the future is radically open.



How could indeterminacy help?


A common argument goes like this: if my behavior is caused by deterministic physical events, then I don’t have free will. But if it’s caused by random physical events, then I also don’t have free will. Sapolsky rightly raises this challenge:


Even if quantum effects bubbled up enough to make our macro world as indeterministic as our micro one is, this would not be a mechanism for free will worth wanting. That is, unless you figure out a way where we can supposedly harness the randomness of quantum indeterminacy to direct the consistencies of who we are. (page 230)


This almost gets us where we need to go, but misses what for me is possibly the most crucial point in this whole debate. For agency to emerge and be exercised, living organisms don’t have to harness the indeterminacy – they just have to take advantage of the causal opportunities it presents.


As my student, Henry Potter, puts it: “Indeterminacy is little more than a pre-condition for agency. It is the background on which a story of agency can be built, not a leading character in that story itself.”


However, Sapolsky continues:


I see two broad ways of thinking about how we might harness, co‑opt, and join forces with randomness for moral consistency. In a “filtering” model, randomness is generated indeterministically, the usual, but the agentic “you” installs a filter up top that allows only some of the randomness that has bubbled up to pass through and drive behavior. In contrast, in a “messing with” model, your agentic self reaches all the way down and messes with the quantum indeterminacy itself in a way that produces the behavior supposedly chosen. (page 231)


This is a nice distinction, but I don’t think either of these models is apt, and a third possibility is not considered. We do indeed use “filtering” mechanisms all the time – that’s how we evaluate possible actions and select one, for example. But this is not, except under certain circumstances where it’s useful, allowing some of the randomness “to drive behavior”. And I agree with Sapolsky that the “messing with” model makes no sense. We don’t need top-down causation to reach a ghostly tendril down and control what would otherwise be a random quantum event. 


The important point is much more fundamental. I’m going to take the odd step of quoting him quoting me:


In the words of Irish neuroscientist Kevin Mitchell, “indeterminacy creates some elbow room. . . . What randomness does, it is posited, is to introduce some room, some causal slack in the system, for higher-order factors to exert a causal influence” (my emphasis). (page 235).


He seems to take me to be arguing here for a “messing with” sort of mechanism, but I’m doing quite the opposite. The causal influence that is exerted is on how the whole system evolves at macro levels. The organism doesn’t care how the system evolves on the micro level. Those details are not relevant. 


As physicist and philosopher George Ellis puts it: "Much randomness occurs at the molecular level, which enables higher functions to select lower level outcomes according to higher level needs."


We don’t need (and generally don’t want) specific random events to determine the outcome. We just need some pervasive indeterminacy to exist such that the low-level forces under-determine the outcome, leaving some room for higher-order organisation to emerge, with causal efficacy over how the system evolves (because the system has been configured in functional ways by natural selection). This is not “messing with”, this is taking advantage of.


Sapolsky disagrees with philosophers Robert Kane and Christian List:


Robert Kane states the same: “We think we have to become originators at the micro- level [to explain free will] . . . and we realize, of course, that we cannot do that. But we do not have to. It is the wrong place to look. We do not have to micro-manage our individual neurons one by one.”


So these free- will believers accept that a neuron cannot defy the physi­cal universe and have free will. But a bunch of them can; to quote List, “free will and its prerequisites are emergent, higher-level phenomena.” (page 192)


While I also disagree with the compatibilist version of these arguments (where fundamental indeterminacy is deemed to be unnecessary for high-level freedom), the general point is sound (especially if we can just help ourselves to fundamental indeterminacy, because that’s our best understanding of the relevant physics).


We really don’t have to micro-manage our individual neurons – that’s the whole point. We don’t have to care what every neuron is doing because the system is configured to be sensitive to the meaning of high-level patterns, not the precise details of every action potential or every synaptic vesicle fusing or ion channel opening.



Emergence and downward causation


The idea that an organism can have causal power, as a whole entity, as a self, depends on concepts of emergence and downward causality. It’s just not possible to grasp the main argument without engaging with these concepts. It is thus disappointing that Sapolsky mostly simply chooses not to:


Thus, a lot of people have linked emergence and free will; I will not consider most of them because, to be frank, I can’t understand what they’re suggesting, and to be franker, I don’t think the lack of comprehen­sion is entirely my fault. (Pages 192-3)


Instead, he argues that:


Emergent systems can’t make the bricks that built them stop being brick-ish (page 202).


That latter point is true, but misses the larger idea, which is simply that the way a system is organised can (non-magically) constrain the behavior of its components, without changing their individual nature.


He states:


…the core belief among this style of emergent free-willers is that emergent states can in fact change how neurons work, and that free will depends on it. It is the assumption that emergent systems “have base elements that behave in novel ways when they operate as part of the higher-order system.” (Page 201).


But if “emergent states” means, for example, what you’re thinking about, then of course that alters how neurons work. That is precisely how nervous systems as a whole work – by one neuron altering how another one is working. And by population dynamics affecting how each individual neuron is working. And by patterns at one level – patterns that mean something – setting the context and criteria for how neurons at another level work. This isn’t magic.


In the same way, the electrons in your computer are constrained by the particular software that’s running. This doesn’t change the properties of the individual electrons, but it absolutely does mean that electrons are behaving differently when they’re in a microprocessor than when they’re not.


It’s thus a shame that Sapolsky does not engage with the kind of literature – by people like Alicia Juarrero and George Ellis, for example – that provides exactly the resources we need to understand how complex systems can be organised in functional ways, where constraints and history are just as crucial to understanding causation as local, instantaneous physical forces.



Mental causation


Perhaps the key stumbling block in understanding how things can be up to us, in a meaningful sense, is the idea of mental causation. Descartes’s dualism left us with the problem of how mental goings-on could possibly influence physical goings-on (discussed in Part 1). The whole point of positing the mental realm was to free our immaterial thoughts from physical determinism, but this does not explain how those immaterial thoughts can then push material stuff around. 


The solution is to realise that thoughts are not immaterial. They are entailed by meaningful patterns of neural activity. Now, you might say that that proves Sapolsky’s point – that what happens in the brain is just determined by these physical patterns. But in fact the workings of the brain are not sensitive to the details of those patterns – they are sensitive to what the patterns mean.


The elements of cognition are not neural firings. They’re higher-order patterns of neural activation that represent beliefs and desires and goals and possible actions. Those patterns are “multiply realisable” – they are macrostates that can be realised by many different microstates. The brain is configured to be causally sensitive to these high-level macrostates – the details of the microstates, in contrast, are arbitrary and incidental.


So, we really do think. Cognition is not an epiphenomenon. Mental states are instantiated by some neural states but cannot be identified with or reduced to them. Neural states have causal influence on the system by virtue of what they mean. Conversely, having a thought, with some particular “content” has causal efficacy in the system because of this physical instantiation. No magic required. Just meaning.


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