Free Will vs. Determinism: What Are We Really Free to Choose?

Welcome, dear readers, to FreeAstroScience. Here’s a question that never leaves us in peace: are our choices truly our own, or are we riding a train whose tracks were laid long before we were born? In this article, written by FreeAstroScience, we explore the classic enigma of free will and determinism—with physics on one side and modern neuroscience on the other. Stay with us until the end: you’ll leave with a clearer understanding of the debate and a practical approach to thinking about responsibility, morality, and what it means to act freely.

What Exactly Do We Mean by Determinism?

According to determinism, everything in the universe is subject to immutable laws governing nature. Each event—including human actions—follows from previous causes and fits into a continuous chain of occurrences. From this causal relationship arises the idea of inevitability: everything that happens is predictable and could not have been otherwise. Consequently, free will and freedom of choice are viewed as illusions, as human behavior would merely result from prior factors, leaving no room for autonomous decision-making.

The principle of universality extends this logic to all domains—physical, biological, and social—asserting that nothing escapes the web of cause and effect. A specific branch, biological determinism, attributes a central role to genetic and physiological characteristics in shaping personality and guiding behavior.

Throughout history, determinism has been interpreted in various ways. Democritus and Leucippus formulated a mechanistic view in which everything results from the motion of atoms. Aristotle developed the notion of causality, the basis of deterministic thought. In the 17th and 18th centuries, Hobbes and Spinoza argued that both nature and human beings are governed by necessary laws. In contrast, Kant reinterpreted determinism as a condition of reason for comprehending the world, rather than as an absolute truth.

In the 19th and 20th centuries, essential critiques emerged: Nietzsche exalted creative and autonomous will; Sartre claimed determinism is an illusion and that humans are free to choose their destiny; Wittgenstein relativized the issue, suggesting that determinism depends on the limits of language and concepts. Outside philosophy, Einstein brought the debate into physics, asserting that fixed, predictable laws govern the universe.

How Does Determinism Affect Our Understanding of Free Will?

Free will, in essence, is the idea that individuals can choose among real alternatives and that their actions are not fully determined by prior causes. This capacity for decision-making is often seen as a prerequisite for moral responsibility. Yet the question remains: how truly free are we? In a universe governed by causal laws, is freedom genuine—or just a sophisticated illusion?

The debate generally divides into two main schools:

• Incompatibilism: If determinism is true, free will is impossible—our actions are merely the inevitable result of previous causes.
• Compatibilism: Even in a determined world, there remains a meaningful sense of freedom, tied to the ability to act according to one’s values, reasons, and character, without external coercion.

The core of the controversy lies in the interpretation of the term “free.” Does being free mean that one could have acted otherwise, keeping everything else equal—or does it mean acting in accordance with what one recognizes as an authentic expression of oneself?

Neuroscience adds new layers to this discussion. Research indicates that many decisions are initiated in the brain before they reach conscious awareness. Experiments suggest that the brain processes information and “decides” at unconscious levels, and that the feeling of control appears only when the decision has already been made and recognized by conscious awareness.
These findings complicate the issue of freedom and moral responsibility. If our actions are partly determined by automatic neural processes, where does conscious choice begin? And if some of what we do stems from mechanisms beyond our control, to what extent can we be considered fully responsible for our actions?

Was Einstein a Strict Determinist About Human Freedom?

Einstein believed the universe is governed by fixed, intelligible natural laws. For him, nothing happens by chance: every event is the inevitable outcome of prior causes, even if not all of them are known. This conviction is summarized in his famous phrase: “God does not play dice with the universe.”

He thus rejected the randomness introduced by the quantum mechanics of Heisenberg and Bohr. For Einstein, apparent quantum chance merely revealed the limits of our knowledge, not a true indeterminacy of nature.

His Theory of Relativity (especially the General Theory, 1915) shows that space and time are not separate entities but parts of a single structure. In this framework, past, present, and future are different aspects of one whole, coexisting as parts of a four-dimensional landscape—the so-called block universe or eternalism.

Everything that has happened, is happening, or will happen exists equally within spacetime. The “now” is merely a limited perspective of an observer within that block.

From a physical standpoint, this eliminates the idea of a flowing time—there is no universal “now” moving forward; time is a dimension, like space. And if the past, present, and future are all “fixed” within the block, the universe appears deterministic by nature: everything is “written” into the geometry of spacetime.

How Do Indeterminacy and Probability Work in Quantum Physics and What’s the Link to Free Will?

Quantum mechanics has brought about a profound shift in our understanding of reality. Unlike classical physics, it shows that subatomic events are not entirely determined but governed by probabilities. Heisenberg’s Uncertainty Principle reveals that we cannot know both the position and momentum of a particle simultaneously and with absolute precision. The wave function, described by Schrödinger’s equation, represents a set of possibilities, only one of which becomes real at the moment of measurement—when the function “collapses.” Thus, nature does not follow strict determinism; there is a genuine element of indeterminacy in particle behavior.

This uncertainty opened space for new reflections on free will. If the universe is not entirely predictable, perhaps the human brain isn’t either—and our decisions could emerge from processes that aren’t fully determined. This idea, known as quantum free will or quantum libertarianism, suggests that physical indeterminacy might sustain a genuine form of mental freedom.

Among the leading defenders of this view are Henry Stapp, a student of Heisenberg, who proposed that consciousness can influence the collapse of the wave function; Roger Penrose, along with Stuart Hameroff, who developed the Orch-OR theory, suggesting that quantum processes in neuronal microtubules are linked to consciousness; and John Eccles, who saw conscious choice as a quantum intervention in the brain. Together with Karl Popper, Eccles argued in The Self and Its Brain (1977) that quantum indeterminacy opens a gap for truly free choices—a possible bridge between physics and human freedom.

What Does Neuroscience Say Today and What Does Sapolsky Argue?

In Determined: A Science of Life Without Free Will (2023), neurobiologist Robert Sapolsky argues that our decisions arise from genes, hormones, neuroanatomy, development, culture, stress, and luck—factors we do not choose. Therefore, he concludes that free will doesn’t exist, or at least not as much as we think. This view challenges traditional notions of guilt, punishment, praise, and merit.

Neuroscience often points to preconscious neural activity that precedes reported decisions—consider Libet’s readiness potentials (1980s) and subsequent studies. This is unsettling if we imagine a conscious “self” making the final decision in the last moment. However, the case is far from closed:

• Methodological concerns: Many experiments study trivial choices (like pressing a button), not complex moral decisions.
• Interpretive debate: Research such as Brass, Furstenberg & Mele (2019) argues that preconscious preparation doesn’t prove conscious reasoning is irrelevant.
• Need for more substantial evidence: Many warn against extrapolating lab results to broad conclusions about freedom and responsibility.

Neuroscience challenges the notion of “original free will”—the idea of a conscious self as a prime cause—but still leaves room for deliberative and integrative roles of consciousness in meaningful actions.

Who Still Defends Free Will and How?

Several perspectives persist:

• Compatibilism: You are free when you act according to your values, reasons, and character, without coercion—even if your psychology has causes. This preserves moral responsibility.
• Neuroscientific defenses: Peter Ulric Tse argues that brain mechanisms can sustain genuine choice and flexible behavior.
• Data reinterpretations: Critics note that laboratory evidence against free will focuses on micro-movements, not life-changing decisions. A Johns Hopkins article, “Science Supports the Existence of Free Will,” highlights this difference.
• Agency-centered theories: Tononi et al. (2022), within the Integrated Information Theory (IIT), propose that the structure of consciousness itself may ground intrinsically authored decisions rather than mere automatic impulses.

Does Neuroscience Really Destroy the Notion of Agency?

Short answer: No—but it reshapes it.

• Yes, many processes begin before consciousness.
• But complex agency involves integration, inhibition, planning, and responsiveness to reasons over time.
• Therefore, free will may not be a momentary spark but a regulatory architecture that develops, reflects, and transforms.

This new view explains why education, therapy, institutions, and culture can change behavior. If agency were just an instant trick, none of this would matter—and yet it does.

What About Justice, Guilt, and Praise?

Sapolsky’s challenge is provocative: if people could not have acted otherwise, why blame them? He suggests focusing on prevention, rehabilitation, and harm reduction.

Many compatibilists respond:

• Responsibility accompanies capacity—to understand rules, respond to reasons, and control impulses over time.
• Accountability can be prospective—it shapes behavior, protects communities, and reinforces norms.
• Guilt and praise can remain proportional and humane, informed by biological and social determinants.

A practical middle path: maintain responsibility but redesign systems to focus on prevention, treatment, and rehabilitation.

What Is the Most Sensible Way to Think About Freedom Today?

A synthesis that respects physics, neuroscience, and daily life:

• Causality is everywhere. Einstein’s view still stands: events unfold under laws.
• The brain is complex. Much happens before consciousness, but conscious deliberation still organizes and redirects behavior.
• Freedom as authorship. Think of free will as the act of owning your actions through reasons, reflection, and self-transformation over time.
• Compassionate policies. If determinants matter, we must design systems that reduce harm and expand opportunity—not merely punish.

Conclusion: Where Does This Leave Our Everyday Lives?

We began with a simple yet unsettling question: are we truly free? We’ve encountered Einstein’s causal cosmos, Sapolsky’s determined brain, and the chorus of compatibilists and agency defenders who refuse to give up responsibility.

The best path, we believe, is to keep causality in view while fighting for authorship—for ourselves and for one another.

When we design homes, schools, courts, and workplaces that foster reflection, responsiveness, and human limits, freedom grows. Perhaps not the mystical kind—but the kind that lets us write better chapters of our lives.

This article was written for you by FreeAstroScience.com, which explains complex science in simple ways.

 

References:

• Albantakis, L. et al. (2022). Integrated Information Theory (IIT) 4.0: Formulating the Properties of Phenomenal Existence in Physical Terms. https://arxiv.org/abs/2212.14787
• Brass, M., Furstenberg, A., & Mele, A. R. (2019). Why neuroscience does not disprove free will. Neuroscience and biobehavioral reviews, 102, 251–263. https://doi.org/10.1016/j.neubiorev.2019.04.024
• Eccles, J.C., & Popper, K. (1977). The Self and Its Brain: An Argument for Interactionism (1st ed.). Routledge. https://doi.org/10.4324/9780203537480
• Hameroff, S., & Penrose, R. (2014). Consciousness in the universe: A review of the 'Orch OR' theory. Physics of Life Reviews, 11(1), 39-78. https://doi.org/10.1016/j.plrev.2013.08.002
• Libet, B., Wright, E., & Gleason, C.A. (1982). Readiness-potentials preceding unrestricted 'spontaneous' vs. pre-planned voluntary acts. Electroencephalography and clinical neurophysiology, 54 3, 322-35 .
• Mahto, N. (2024). Science supports the existence of free will. The Johns Hopkins News-Letter. Available at: https://www.jhunewsletter.com/article/2024/04/science-supports-the-existence-of-free-will
• Sapolsky, R. M. (2023). Determined: A Science of Life Without Free Will. New York: Penguin Press.
• Stapp, H. P. (2007). Mindful Universe: Quantum Mechanics and the Participating Observer. Berlin: Springer.
• Tononi, G., Albantakis, L., Boly, M., Cirelli, C., & Koch, C. (2022). Only What Exists Can Cause: An Intrinsic View of Free Will.  https://arxiv.org/abs/2206.02069
• Tse, P. U. (2013). The Neural Basis of Free Will: Criterial Causation. Cambridge, MA: MIT Press.