Can There Be Evidence for Free Will?

In an essay, science writer John Horgan talks about why, despite being essentially a materialist, he believes in free will. He doesn’t seem to think there is much evidence for it and he struggles with superdeterminism as evidence against it:

And to be honest, “proofs” of free will seem as dubious to me as denials. Proofs tend to equate free will with randomness and unpredictability. My choices, at least important ones, are neither random nor unpredictable, at least for those who know me.

For example, here I am arguing for free will once again. I do so not because physical processes in my brain compel me to do so. I defend free will because the idea of free will matters to me, and I want it to matter to others. I fear deterministic views of human nature undermine efforts to combat sexism, racism and militarism.

If pressed, I’ll concede that ‘t Hooft could be right. I might be a mortal, 3-D, analog version of the “Speed Demonoid,” plodding from square to square, my thoughts and actions determined by rules beyond my ken.

But I hate to accept that grim worldview. Life without free will lacks meaning, and hope. Especially in dark times, my faith in free will consoles me, and makes me feel less bullied by the deadly, all-too-real game of life. 

“Quantum Mechanics, Free Will and ‘The Game of Life,’” Cross-Check, February 4, 2024

Superdeterminism?

Nobel laureate Gerardus ‘t Hooft rules out free will based on the concept known as superdeterminism. Here’s a quick explanation:

Superdeterminism is a technical term for a specific application of determinism, postulating that there is no statistical independence between a measurer, with his detector interacting with the particle to measure it, and the particle itself. In other words, the universe is so thoroughly deterministic that it will force any seemingly random, freely made measurement to produce some value correlated to other measurements. 

Tom Hartsfield, “Superdeterminism: To better understand our Universe, ditch the idea of free will,” Big Think, August 29, 2022

However, as Horgan notes, there is no consensus on that. Stephen Wolfram proposes that, on the contrary, free will is still possible. And so do others.

Quantum mechanics is actually a minefield of counterintuitive findings all around so it’s a good question sometimes whether thinkers will see in it a reflection of their own prior beliefs.

Horgan’s view seems based in part on an emotional refusal to accept a lack of free will. But that is not nearly as bad a place to begin as it might at first seem. If something sounds unnatural and unreasonable, we should not think that we must have hard evidence before we delay accepting it and choose to look further instead. Chances are, we will be proven right.

What Do We Consider as Evidence for Free Will?

Interestingly, Horgan thinks that “proofs” of free will seem as dubious as denials. “Proofs tend to equate free will with randomness and unpredictability.” But that depends on what we consider “proofs.” And it certainly does not represent what is happening in neuroscience.

As Cristi L. M. Cooper notes in an excerpt from Minding the Brain (Discovery Institute Press, 2023), there is an entire field of experimental investigation that has found robust evidence for free will in humans, in practice. Commenting on her survey of the findings, she notes,

Indeed, although the vast majority of neuroscientists believe in a deterministic view of free will, many of them do not believe that Libet’s experiment can be shown to do away with free will. In a useful review in the journal Neuroethics, Andrea Lavazza and Mario De Caro provide examples of conceptual confusion surrounding neuroscientific studies on human agency. Their conclusion is spot-on: “Our aim here has only been to suggest that, when one comes to the issue of human agency, great caution should be used before drawing bold philosophical, political and social conclusions from neurological findings, whose correct interpretation and value are still extremely controversial.” This is the aim of this chapter, too.

They add that there are “plenty of excellent reasons for believing that neurobiology will continue to enrich our understanding of many features of the human mind, but there are no good reasons for thinking that it is going to fully explain them all.” Neuroscience has told and will continue to tell us much about the brain as the organ that carries out the actions of the mind, and we have to continue to have conversations about what the science means. The scientists would do well to remain open to philosophical considerations that span the spectrum of thought on free will and, likewise, the philosophers would be wise to ground their ideas in what has been demonstrated regarding the human brain and body. 

“How neuroscience disproved free will and then proved it again,” Mind Matters News, February 13, 2024

As we’ve noted earlier, neuroscience has never disproven free will, much as some neuroscientists may have wanted it to.

As for quantum mechanics and other physics, Dartmouth College theoretical physicist Marcelo Gleiser warns,

Fortunately, the mind is not a solar system with strict deterministic laws. We have no clue what kinds of laws it follows, apart from very simplistic empirical laws about nerve impulses and their propagation, which already reveal complex nonlinear dynamics. 

“Do the laws of physics and neuroscience disprove free will?”, Big Think, November 10, 2021

So Horgan may have more going for his instincts than he thinks. And, as neurosurgeon Michael Egnor, author with me of The Immortal Mind (Worthy June 3, 2025), points out, “denial of free will is a quick route to totalitarianism. If you can’t be guilty because you can’t choose, you can’t be innocent either. In fact, you must be controlled by the powers that be for your own good. So you can’t really have the rights or dignity that a free society accords to human beings.”

But if we can even see that problem, we are not automatons.