The existence of free will in a potentially deterministic universe is one of philosophy's most enduring puzzles. Positions fall into categories like Hard Determinism (no free will, as everything is determined), Libertarianism (genuine free will exists and is incompatible with determinism), and Compatibilism (free will and determinism can coexist). This article presents one perspective within this rich debate, exploring how the powerful and subjective experience of free will can arise and persist for agents operating within a deterministic universe, without necessarily resolving deeper metaphysical questions for everyone. We will argue that, for complex, deliberative agents like humans, this experience is effectively unavoidable from their embedded viewpoint.
Determinism posits that every event, including human thought and action, is the inevitable consequence of prior causes and natural laws. If we knew the universe's precise state at one moment – a hypothetical capability sometimes called Laplace's demon – we could, in principle, predict the entire future. This objective view seems to leave no room for genuine free will as intuitively understood by many – the sense of making choices not fully predetermined.
However, our focus is on the perspective of an embedded agent – an agent, like a human or AI, that exists inside the system it tries to understand and interact with. An embedded agent cannot step outside the universe to gain a complete, God's-eye view of all variables influencing its state and environment. This limitation means an embedded agent cannot perfectly know all factors determining its future actions, even in a deterministic universe.
Consider two agents created to be absolutely identical, placed in identical initial conditions. In a perfectly deterministic system, if truly isolated, they would theoretically follow identical paths forever. This highlights the deterministic premise: same cause, same effect.
However, imagine these agents embedded within a complex, shared environment – like our universe. Even starting identically, they will inevitably encounter minute environmental differences over time. Slight variations in light, air pressure, or even random quantum fluctuations (with downstream effects) – processed by their complex, deterministic internal states – will lead to diverging experiences, memories, and states.
Does this mean the agents are making genuinely undetermined choices? From a deterministic perspective like the one presented here, no. Their actions are still the determined result of their (now slightly different) internal states interacting with their (now slightly different) environments.
The crucial point from this perspective is that divergence arises not from overriding deterministic laws, but from accumulating unique inputs processed by deterministic mechanisms. Each agent's subsequent state and actions are determined by its prior state and the specific environmental inputs it received. Since those inputs diverged, their determined paths also diverge.
From the perspective of each embedded agent, the situation feels very different. Lacking complete information about every factor influencing their decisions – from neural firing patterns to external stimuli – they cannot perfectly predict their own future actions. Faced with a decision, they experience deliberation, weighing options, and making a choice.
This inability to deterministically predict one's own actions from an internal, embedded viewpoint creates the subjective experience of free will. This is a powerful feeling of autonomy arising from our position as limited agents within a complex system, rather than necessarily reflecting metaphysical freedom from causal laws. For complex, deliberative agents, this feeling is effectively unavoidable. While believers in genuine, undetermined free will may disagree, this perspective explains the feeling itself.
This phenomenon is analogous to limitations in mathematics and computer science, such as Gödel's incompleteness theorems (truths within a system unprovable by that system) or the Halting Problem (impossibility of a general algorithm to predict if any program will finish). Similarly, an embedded agent cannot fully model or predict its own future from within its system.
From the embedded perspective, the feeling of "I could have chosen otherwise" stems from our limited viewpoint. Reflecting on a past decision, we easily imagine a different choice if a slight input (internal thought, external information) had differed. This capacity for counterfactual thinking, combined with our inability to perfectly predict our own determined actions, fuels the powerful intuition of alternative possibilities.
Furthermore, understanding free will as a subjective experience within a deterministic framework doesn't necessarily dismantle the basis for moral responsibility from this perspective. Responsibility can be understood via an agent's capacity for rational deliberation, understanding consequences, and responsiveness to reasons and social norms. These capacities function and are meaningful within a deterministic system because they allow agents to effectively navigate their environment and respond to social feedback. We hold agents responsible because their actions result from their (determined) beliefs, desires, and deliberative processes, which can be influenced by praise, blame, and consequences – these social responses act as part of the deterministic system shaping future determined behavior. This view grounds responsibility in the agent's actual functioning within the system, not requiring a break in the causal chain.
Even if the universe is deterministic, the experience of free will is not diminished for embedded agents like ourselves. Our complexity and inability to gain complete self-knowledge ensure we genuinely experience making choices. This subjective reality of deliberation and decision-making is unavoidable for agents like us and profoundly shapes our lives, interactions, and self-understanding.
The interplay between determinism and embedded agency offers a compelling way to reconcile the objective possibility of a determined universe with the undeniable subjective reality of feeling like we are free agents. It highlights that our experience of free will is not a mere error, but an emergent and essential property of being a conscious, limited agent navigating a complex world. Exploring the complex relationship between determinism, consciousness, and agency is a rich field, and this article offers one lens through which to view it.