Written by Kevin J Mitchell

EVOLUTION MAKES US FREE!

Review by Steve Minett

This book considers the question of free will. Much of its philosophical heavy-lifting (of which there is a lot), consists of reformulating the traditional question, e.g. denying that the answer is limited to either simplistic physical determinism, at the level of atoms or quantum fields, or to some kind of magical dualism. (pxi) The author, Kevin Mitchell, argues that the way to escape these traditional, intellectual cul-de-sacs is to ‘ground’ the concepts of purpose, meaning, and value in a scientific conceptual framework which naturalises the concept of agency. He insists that these concepts, far from being unscientific; “… are crucial to understanding what life is, how true agency can exist, and what sorts of freedoms or limitations we actually have a human beings.” (pxi) And the trust of this book asserts that we really are free agents: “We make decisions, we choose, we act – we are casual forces in the universe. These are the fundamental truths of our existence.” (p18) However, Mitchell adds that the question of free will does not have a yes-or-no, all-or-none answer. Rather, we have degrees of freedom: we have the ability to make choices, which means that our;  “actions are not simply determined by outside forces because we’re causally set apart from the rest of the universe to at least some degree. And, just as importantly, we are not driven by our own parts. Rather, we, holistically—our selves—are in charge.” (p279)

Michell deconstructs the question; “Do we have free will?” – by asking ‘who is we?’ ‘What does “free” mean (in this context)?’ As he says, ignoring these questions fails to met the challenge of physical determinism by merely sidestepping it with appeals to complexity and unpredictability. (p17) By thus shifting the perspective, the reductive view of linear pathways, with dedicated components is revealed as an illusion, which; “… encourages the view of cells or organisms as stimulus–response machines when really they are holistic, proactive, dynamic systems acting in a goal-directed manner; that is, they are agents. They’re not pushed around by things in the world, and they’re not pushed around by their own parts.” (p292)

Much of this convenient and conventional intellectual fudge is encapsulated in the philosophical concept of ‘compatibilism’. This s the belief that free will and determinism are mutually compatible and that it is possible to believe in both without being logically inconsistent. Mitchell suggests that compatibilism is the mainstream view of most scientists and philosophers. But, as Mitchell explains, it’s unconvincing: “… to argue that we can treat humans and other organisms as if they have some causal power, even though we know that they are not really making choices. … only because they are so complicated that, for all practical purposes, we can and should treat them as reasoning agents with the capacity to act, and not just as complex arenas in which the laws of physics play out.” (p152)

Mitchell asks: “How can an agent be the real causal source of an action when everything that happens in the universe is fully determined by what happens at the lowest levels?” (p153) Indeed, he even suggests that the very concept of causation may be meaningless in a universe characterised by hard determinism: if everything is generated by endless causal chains, why arbitrarily label one link ‘cause’ and the next ‘effect’? Mitchell says that; “… compatibilist arguments build an ‘as-if’ picture of human free will … justifying moral responsibility while side-stepping the more fundamental problem that agency – the power of an organism to choose an action at all – is ruled out by physical pre-determinism.” (p154) Fortunately, however, these arguments fail, because this kind of determinism is refuted by quantum physics.

Mitchell points out that indeterminacy at the lowest levels can indeed introduce indeterminacy at higher levels. (p159) But, he concedes that just adding randomness doesn’t solve the problem: “If my actions are controlled by random physical events at the level of subatomic particles in my brain, then I am no more in charge of them than if they were fully physically predetermined.” (p163) However, what the introduction of chance crucially contributes to free will is to undercut; “… necessity’s monopoly on causation. The low-level physical details and forces are not causally comprehensive: they are not sufficient to determine how a system will evolve from state to state. This opens the door for higher-level features to have some causal influence in determining which way the physical system will evolve.” (p163) This means that the organisation of the system can also do causal work: “In the brain, that organisation embodies knowledge, beliefs, goals, and motivations – our reasons for doing things. This means some things are driven neither by necessity nor by chance; instead, they are up to us.” (p164) Thus, physical indeterminacy creates ‘causal slack’, which opens the door for ‘top-down causation’.”  

So, if changes at the low-level have unpredictable impacts, then simple reductionism is not deterministic: something else is generating the space for agency. Mitchell claims that this ‘something else’ is the way the system is organised: this organisation evolves through time, driven by the patterns meaning in neural circuits, and this meaning arises from the history of interactions of the organism with its environment and is embodied in the patterns of synaptic connectivity between individual neurones. “In this way, abstract entities like thoughts and beliefs and desires can have causal influence in a physical system. … Patterns of neural activity only have causal efficacy in the brain by virtue of what they mean. Of course these higher-order abstract entities must be instantiated in a physical medium, but they are not reducible to the underlying physical mechanisms. Nor do they magically just emerge from those mechanisms. The meaning of the various (often arbitrary) neural patterns arises through the grounded interaction of the organism with its environment over time.” (p212)

This means that the causal freedom of a system depends on the way it is configured: “In living organisms, that configuration itself is the outcome of selection over millennia and over the lifetime of the organism itself, on a timescale of seconds to hours to years.” (p164) In addition, causation is not wholly instantaneous. All this leads Mitchell to the conclusion that; “… if higher-order features and principles can exert causal power in a system – then causal determinism poses no threat to concepts of agency and free will. The agent itself can be the cause of something happening.” (p165) Having this ability requires selfhood, which is defined by continuity through time, i.e. maintaining a certain dynamic pattern of processes in the face of thermodynamic pressure toward randomness: “In humans, this activity includes maintaining the continuity of our psychological, biographical selves: all the memories and experiences and relationships; all the learnings, the habits and heuristics and policies; the commitments and projects and long-term goals; and all the dispositions that go with them. It means using the hard-won knowledge accumulated by your past self to guide action in the present moment in the service of your future self.” (p279)

As Mitchell points out, these are consistent with process philosophy (as promoted by Alfred North Whitehead and Henri Bergson), which he defines as; “the view that processes, rather than static isolated objects or substances, are the fundamental elements of reality.” The idea is that everything we see is really something in flux, changing through time, with some things changing much more rapidly than others. This view recognises that time is not made up of static instants, in which the state of reality can be frozen and defined in precise detail. Rather, it is made of durations during which everything is in some degree of flux.” (p291) (Michel notes that process philosophy fell out of favour for almost a century but seems to be gathering support again, especially in the philosophy of biology.)

The book ends with a revealing discussion of AI in relation to free will. Mitchell observes that AI has been singularly unsuccessful at tasks which humans and many animals find easy, such as moving around in the world, understanding causal relations, or knowing what to do in novel situations. (p296) By way of explanation, Mitchell says that AI systems; “… may ‘know’ that when they see X, it is often followed by Y, but they may not know why that is: whether it reflects a true causal pattern or merely a statistical regularity, like night following day. They can thus make predictions for familiar types of data but often cannot translate that ability to other types or to novel situations.” (p296) He points out how this differs from ‘biological intelligence’, which has; “… the ability to act appropriately in novel and uncertain environments by applying knowledge and understanding gained from past experience to predict the future, including the outcomes of their own possible actions.” (p297) In addition, ‘biological intelligence’ has; “… the ability not just to arrive at an appropriate solution to a problem but to do so efficiently and quickly. Living organisms do not have the luxury of training on millions of data points, or running a system taking megawatts of power, or spending long periods of time exhaustively computing what to do.” (p297)

Mitchell himself identifies the claim that the functional organisation of a system can have causal power as one of the book’s major themes. This, in turn, requires the view that; “…the currency of the nervous system is meaning: that’s what causally drives the mechanism. This is not just information in an abstract mathematical sense but information about things, interpreted in the context of stored knowledge, with potential consequences for behaviour. The organism is not mechanically driven by stimuli from outside; it is interpreting these signals in its capacity as a self. The organism is meeting the world halfway, as an active partner in a dance that lasts a lifetime.” (p217) As per process philosophy, Mitchell concludes that: “These views are essentially holistic, even ecological: they consider the dynamics of a system in the context of all its relations, both internal and external. For a process as richly complex as life, this feels to me like the right approach.” (p291)

Published by Princeton University Press, 2023, 352 PP, ISBN 978-0691226231

About the author; Kevin Mitchell is a neurogeneticist interested in the relationships between genes, brains, and minds. He is a faculty member at Trinity College Dublin, Ireland, in the departments of Genetics and Neuroscience. He writes the Wiring the Brain blog (www.wiringthebrain.com) and is on Twitter @WiringtheBrain.

About Dr Steve Minett; Author of Consciousness as feeling: a theory of the nature and function of consciousness and How Consciousness Probably Works (available from amazon or https://consciousvm.wordpress.com/)