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Why Do Atheists Still Claim Free Will Can’t Exist?

Sam Harris reduces everything to physics but then ignores quantum non-determinism

Michael Clunn: Do you know of a guy named Sam Harris who runs a podcast called Making Sense? His ideas are definitely in your area of studies so I was curious if you’ve come across him before.

I’m listening to a podcast of his “Cause & Effect: A Conversation with Judea Pearl” (#164):

In this episode of the podcast, Sam Harris speaks with Judea Pearl about his work on the mathematics of causality and artificial intelligence. They discuss how science has generally failed to understand causation, different levels of causal inference, counterfactuals, the foundations of knowledge, the nature of possibility, the illusion of free will, artificial intelligence, the nature of consciousness, and other topics.

Judea Pearl is a computer scientist and philosopher, known for his work in AI and the development of Bayesian networks, as well as his theory of causal and counterfactual inference. He is a professor of computer science and statistics and director of the Cognitive Systems Laboratory at UCLA. In 2011, he was awarded with the Turing Award, the highest distinction in computer science. He is the author of The Book of Why: The New Science of Cause and Effect (coauthored with Dana Mackenzie) among other titles.

Harris basically reduces everything to atomic physics and says all causality happens there, so the world is deterministic (i.e. no free will). While I vehemently disagree with that idea, I do respect that at least he can articulate himself well.

Do you have any thoughts on the matter?

Eric Holloway: A deterministic physical world does not imply that free will doesn’t exist. Look at it as an argument in four steps:

  1. Free will is not deterministic.
  2. The physical world is deterministic.
  3. ?
  4. Free will does not exist.

Harris needs to fill in missing step 3 to arrive at his conclusion. One possible premise is that the physical world is all that exists. But, Harris would need to demonstrate that point. It isn’t obviously true.

For instance, things like mathematics and consciousness seem to exist, and also seem to not be reducible to physics, i.e. I cannot physically destroy the number one, and I remain the same conscious person even if all my atoms are changed.

Also, there is quantum physics, which is not deterministic. So, even if the physical world is all that exists, it isn’t deterministic. So premise #2 is false.

Michael Clunn: Lol. My first thought was of quantum physics. If that is probability-based, rather than dependent on point particles interacting with each other, then there is no way to have a fundamentally deterministic world. That would prove specifically that free will must necessarily exist.

An interesting corollary to that (as it seems to me) is that it would also mean that an emergent level of consciousness could then actually interact with a lower level domain while still not being reducible. Your consciousness could alter the physical environment (I. E. Neurons and such).

I’m also skeptical of anyone who regards consciousness purely as a system for information processing and of no other use. But that is a topic for another day.

Further reading on free will: Younger thinkers now argue that free will is real. The laws of physics do not rule it out, they say.

Quantum randomness gives nature free will. Whether or not quantum randomness explains how our brains work, it may help us create unbreakable encryption codes. (Robert J. Marks)


Do quasars provide evidence for free will? Possibly. They certainly rule out experimenter interference.

Mind Matters News offers a selection of articles on free will by neurosurgeon Dr. Michael Egnor on free will, including

Is free will a dangerous myth? The denial of free will is a much more dangerous myth.

Can physics prove there is no free will? No, but it can make physicists incoherent when they write about free will. It’s hilarious. Sabine Hossenfelder misses the irony that she insists that people “change their minds” by accepting her assertion that they… can’t change their minds.

Does “alien hand syndrome” show that we don’t really have free will? One woman’s left hand seemed to have a mind of its own. Did it? Alien hand syndrome doesn’t mean that free will is not real. In fact, it clarifies exactly what free will is and what it isn’t.

How can mere products of nature have free will? Materialists don’t like the outcome of their philosophy but twisting logic won’t change it.


Does brain stimulation research challenge free will? If we can be forced to want something, is the will still free?

Featured image: Choosing one’s perspective/Chuttersnap, Unsplash

Eric Holloway

Senior Fellow, Walter Bradley Center for Natural & Artificial Intelligence
Eric Holloway is a Senior Fellow with the Walter Bradley Center for Natural & Artificial Intelligence, and holds a PhD in Electrical & Computer Engineering from Baylor University. A Captain in the United States Air Force, he served in the US and Afghanistan. He is the co-editor of Naturalism and Its Alternatives in Scientific Methodologies.

Why Do Atheists Still Claim Free Will Can’t Exist?