Leslie Allan
5 min
Leslie Allan argues that the long-standing philosophical debate over free will is largely based on a misunderstanding of how the term is used in everyday life. While libertarians and hard determinists often assume that 'free will' requires a contra-causal will—one that operates outside the laws of physics—Allan contends that this is a technical, specialized definition. In common parlance, as well as in legal and medical contexts, a 'free act' is simply one that is not restricted by specific external or internal encumbrances.
To formalize this, Allan introduces the '4C theory,' which identifies four necessary conditions for an act to be considered free. An act is free only if it is not: (1) Compelled by external pressure, (2) Controlled by a third party, (3) Inconsistent with the agent's established character, or (4) Impaired by a lack of cognitive ability to reason. By focusing on these four factors, Allan demonstrates that we can maintain a robust, practical notion of moral responsibility that is entirely consistent with a deterministic, scientific view of the human brain.
Central to the debate is the phrase 'could have done otherwise.' Incompatibilists argue that in a deterministic world, we could never have done otherwise, thus rendering us unfree. Allan counters this by distinguishing between two senses of the phrase. The 'PLIC' sense (Physical Laws + Initial Conditions) is what scientists use to predict physical systems, while the 'PLUC' sense (Physical Laws + Unchanged Character) is what we use in daily life. When we say someone 'could have done otherwise,' we are not claiming they could have broken the laws of physics; we are saying that, given their character, they would have acted differently if the external circumstances had been different. This analysis allows us to preserve our moral intuitions without needing to invent unscientific, 'magical' causes for human behavior.
This paper provides a framework for reconciling our scientific understanding of the brain with our social and legal practices of praise, blame, and responsibility. By showing that our moral systems do not require contra-causal freedom, Allan suggests that we can move toward a more humane and evidence-based approach to justice, focusing on rehabilitation and deterrence rather than retributive punishment.
Sam: Which raises an interesting implication. If folk practice is already doing the compatibilist work, then the incompatibilist worry about determinism is a solution to a problem that our actual practices never had.
Alex: Allan pushes this further with a point about counterfactual reasoning. Asking what an agent would have done under different circumstances—the basis of praise and blame—requires a stable, law-like relationship between character and action. If actions were genuinely uncaused, that reasoning collapses entirely. Determinism isn't the threat to moral responsibility; it's what makes moral reasoning tractable in the first place.
Sam: That's a genuinely counterintuitive move. The thing incompatibilists treat as the problem turns out to be load-bearing for the solution.
Alex: And it has downstream implications for punishment. If the 4C framework is right, the logical direction for criminal justice isn't retribution—it's rehabilitation and risk management. You're not sanctioning someone for a metaphysical failure to be uncaused. You're responding to a profile of character and cognition that produced harmful behavior, with an eye toward changing it.
Sam: That's a compelling argument. But a careful referee would push back on using ordinary language as the foundation. Folk intuitions can be systematically mistaken—they're not always a reliable guide to what's actually happening in cognition or decision-making.
Alex: That's the primary constraint on the paper's reach. Allan's approach is descriptive and semantic, not neurobiological. He's mapping how we use the term "free will," not explaining the mechanisms that underlie deliberation and choice. It's a coherent semantic solution, but it leaves the mechanistic question largely untouched. Whether our folk categories carve cognition at its joints is a separate question the paper doesn't resolve—and a referee working from cognitive science would want that gap addressed.
Sam: So the paper's contribution is clarifying what the debate is actually about—and showing that much of the incompatibilist argument rests on a mismatch between metaphysical ambition and ordinary usage.
Alex: That's the core of it. Allan's argument is that "free will" is a category for identifying agency, not a hypothesis about the fundamental structure of causation. Once you accept that framing, the apparent conflict between determinism and moral responsibility largely dissolves—not because the metaphysics is settled, but because it was never the right place to look.
Sam: That reframing alone seems worth the read. Thanks for walking through it, Alex.
Alex: Thanks for listening to ResearchPod.