Free will as a process of generative self-construction, by which an iterative search process samples from experience in an adaptively exploratory fashion, allowing the agent to explore itself in the construction of alternative futures

Neurocognitive free will. Thomas T. Hills. Proceedings of the Royal Society B, Volume 286, Issue 1908. July 31 2019. https://doi.org/10.1098/rspb.2019.0510

Abstract: Free will is an apparent paradox because it requires a historical identity to escape its history in a self-guided fashion. Philosophers have itemized design features necessary for this escape, scaling from action to agency and vice versa. These can be organized into a coherent framework that neurocognitive capacities provide and that form a basis for neurocognitive free will. These capacities include (1) adaptive access to unpredictability, (2) tuning of this unpredictability in the service of hierarchical goal structures, (3) goal-directed deliberation via search over internal cognitive representations, and (4) a role for conscious construction of the self in the generation and choice of alternatives. This frames free will as a process of generative self-construction, by which an iterative search process samples from experience in an adaptively exploratory fashion, allowing the agent to explore itself in the construction of alternative futures. This provides an explanation of how effortful conscious control modulates adaptive access to unpredictability and resolves one of free will's key conceptual problems: how randomness is used in the service of the will. The implications provide a contemporary neurocognitive grounding to compatibilist and libertarian positions on free will, and demonstrate how neurocognitive understanding can contribute to this debate by presenting free will as an interaction between our freedom and our will.

1. Introduction

Free will can be defined as the ability to be free from one's past and yet to simultaneously act in accordance with one's will. This is an apparent paradox because it requires that free will be an ahistorical process governed by a historical identity. The goal of this article is to show that by grounding the design features of free will called for by philosophers in a contemporary understanding of neurocognitive capacities we can resolve this paradox and understand how free will could work in a neurocognitive system.

The design features of free will have been proposed by two primary philosophical camps: the compatibilists—who hold that free will is compatible with a deterministic universe—and the libertarians—who hold that free will is compatible with an indeterministic universe. The classical compatibilists (such as Hobbes, Locke, Leibniz, Mill and Hume) claim that an agent has free will if it could have done otherwise. The neo-compatibilists (such as Frankfurt, Watson and Bratman) claim that an agent has free will when lower-order desires are aligned with higher-order desires, sometimes called ‘wanting what you want’, which invokes a hierarchy of wants and volitions that some argue presupposes a wanting ‘self’. The libertarians (such as Descartes and Kant) claim that an agent has free will if this conscious self can rationally escape the causal certainties of determinism [1,2].

Discussions of free will have thus far failed to describe how these requirements could be met by a neurocognitive system. This has hampered progress on understanding how free will could work and enfeebled our understanding of ourselves at the same time. As a result, many have provocatively claimed that free will is an illusion because unconscious neural activity at least sometimes precedes or influences conscious activity [3–5]. If consciousness is bypassed in the decision-making process then the worry is ‘that the causal chain leading up to our actions bypasses the self’ [6], eliminating the kind of free will that many people want [7,8]. Indeed, many of these provocative claims point to unconscious ‘bottom-up’ control and use it to argue that a system has no conscious ‘top-down’ control (for a variety of arguments on both sides see [4,9–13]).

However, without an explanation of how a biological system could satisfy the design features of free will, we risk logical fallacies based on mistaking parts of the system for the whole. To overcome this, we first need to understand how free will could work as a set of neurocognitive processes. We can then assess free will in relation to an operationalized architecture that is grounded in biological reality—treating free will as a quantitative trait [14,15].

Before getting to the design features, it is useful to first define what I mean by conscious control as we will revisit this idea throughout. Conscious control processes are effortful, they focus attention in the face of interference, they experience information in a serial format (one thing at a time), they can generate solutions that are not hard-wired, and they operate over a constrained cognitive workspace—working memory—to which ‘we’ have access and can later report on as a component of conscious awareness [16–20]. When additional tasks are added to consciously effortful tasks performance suffers. Effortful processes sit in contrast to automatic processes, which are fast and parallel, and do not require conscious awareness. Effortful tasks can be made automatic through repetition (like reading and driving [21]) and when they become automatic they suffer less from the addition of a secondary task. Effortful and automatic processes are typically thought to sit at opposite ends of a continuum and the evidence provided below shows that they can influence one another.

The relationship between effortful processing (sometimes called executive processing) and conscious control is well documented (e.g. [16,18,22]). If we identify effortful consciousness with the self and this effortful self plays a role in satisfying the design features of free will discussed in further detail below, then what people mean by and want from free will are satisfied by our neurocognitive capacities.