In an intellectually rich discussion on Mind Matters News, neurosurgeon Dr. Michael Egnor and host Dr. Robert J. Marks explore the scientific, philosophical, and theological dimensions of free will, determinism, and the immaterial nature of the soul. The conversation centers around contents of the new book The Immortal Mind by Egnor and Denyse O’Leary. What emerges is a compelling case not only for the reality of free will, but also for the immortality of the human soul, grounded in reason and neuroscience.

The self-refuting nature of free will denial

The conversation begins with an analogy: If a spilled bottle of ink coincidentally formed the words “It’s going to snow,” no one would believe that message had real meaning. Similarly, Egnor argues, if human thoughts are just the result of chemical reactions or dopamine levels in a “meat robot,” then there is no reason to believe they convey truth. To claim, “There is no free will,” is to make a rational argument while denying the very capacity—free rational agency—that makes rational argument possible. This is, he says, self-refuting.

Physics: Bell’s inequality and the death of determinism

Egnor continues by addressing determinism from a physics standpoint. Many who deny free will appeal to determinism, claiming all actions are governed by physical laws. However, quantum mechanics challenges this view. French physicist Alain Aspect, building on John Bell’s theoretical work, performed initial experiments that disproved local determinism. This finding—recognized with a Nobel Prize—shows that at the quantum level, events are not strictly determined. As Egnor puts it, if determinism is false at the foundational level of reality, then it cannot serve as a basis to deny free will.

Neuroscience and “free won’t”

Egnor next turns to neuroscience, citing two influential figures: Wilder Penfield (1891–1976)  and Benjamin Libet (1916–2007). Penfield, a pioneer in awake brain surgery, discovered that while he could stimulate a patient’s motor cortex to cause physical actions, patients always knew whether they had freely chosen the action or had been manipulated. In decades of work, not a single patient was fooled into thinking an involuntary movement was willed.

Libet, in turn, explored the timing of decisions and discovered a brain signal preceding conscious intent to act — seemingly undermining free will. But his follow-up studies introduced the idea of a “veto,” where subjects could suppress the action. Crucially, this veto showed no corresponding brain signal, implying that the act of not doing something — the exercise of “free won’t” —originates beyond physical brain activity.

God, time, and free will

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Marks then introduces a theological tension: If God knows all our future choices, how can free will exist? Egnor acknowledges this age-old dilemma but offers a helpful analogy from engineering: time and frequency domains. Just as reality can be represented in different ways mathematically, perhaps God’s view of time is like the frequency domain — timeless and comprehensive. God sees all events but does not force them. Thus, divine foreknowledge does not negate free will.

They agree that free will is integral to being made in the image of God. Reason and moral choice reflect the divine.

Abstract thought and the immortality of the soul

Egnor shifts the discussion to a Thomistic argument: our ability to comprehend abstract concepts — such as infinity, logic, or mathematics — demonstrates the immaterial nature of the intellect. Physical matter, including the brain, cannot account for this ability.

He illustrates this with the example of the number eight. As a written figure, it can be destroyed; as an abstract concept, it cannot. Similarly, while the body may decay, the immaterial powers of the soul — intellect and will — do not disintegrate, suggesting the soul’s immortality. Death is a physical disintegration, but the soul, being immaterial, does not decompose.  

Young minds and the need for meaning

Marks shares anecdotes from students who were deeply moved by this line of reasoning. Though initially concerned the ideas might be too abstract for younger audiences, he found that students readily grasped and were energized by them. Egnor concurs, noting that today’s youth are overwhelmed by materialism and crave meaning. Abstract reasoning about the soul gives them hope that they are more than biological machines.

Christianity as a response to modern malaise

The episode concludes on a hopeful note. Marks reflects on the modern psychological malaise fueled by social media and materialistic culture. Christianity, he suggests, offers a powerful counter-narrative: that individuals are loved, valuable, and eternal. Egnor agrees, observing that since becoming a Christian, he no longer experiences the existential malaise that often burdens secular thinkers.

Take aways

The conversation between Egnor and Marks weaves together neuroscience, quantum physics, philosophy, and theology to make a robust case for free will and the immaterial human soul. In an age increasingly dominated by reductionism and materialism, they offer a vision of the human person as rational, free, and made for eternity — a view that resonates deeply with both ancient wisdom and modern science.