Ghosts, Zombies, & Substance Dualism



(The FreeThinking Theist)


April 20, 2017


Tim, have you seen that CERN has provided scientific proof that the soul (or the “ghost in the machine”) does not exist! Too bad for your Freethinking Argument! This scientific data does fatal damage to the Interactionist Substance Dualism you argue for because the only way for an immaterial substance to move a material object is to create energy ex nihilo (as energy transfer is necessary to move a material object).

The problem is that if there is this external energy moving material objects this way then it would be scientifically detectable with relative ease. Since this energy has not been detected, but would be if the energy existed and Interactionist Substance Dualism is true, then, Interactionist Substance Dualism is false.


 Tim’s Response

The experiments done at CERN with the Large Hadron Collider (LHC) are amazing and I always find their discoveries fascinating. With that said, however, you seem to be a little too eager with your conclusions. In fact, your objections are logically fallacious. This is the case because you attack a straw man!

First, the Freethinking Argument does not conclude that substance dualism is true; rather, it deductively concludes libertarian free will exists, the soul exists and that naturalism is false. So, my argument leaves ontological idealism on the table as a possibility. Second, the view you attack is not the view of the soul that I hold nor the view of the soul that I argue for. The soul is not a “source of energy,” but rather, the soul freely chooses to think and freely chooses to use the available energy that is already there. That is to say, the energy would be used one way or the other apart from the soul, but with the soul, now you have a choice regarding how you are going to use the energy available.

Trucks & Gasoline

Think of it this way: if my truck is full of gasoline then I can freely choose to drive it to McDonalds or Burger King — or I can freely choose not to drive it anywhere and make a healthy meal at home. However, if my truck is completely out of gas, then I cannot drive it anywhere — even if I wanted to and even if I tried!

Similarly, if my body has available energy, then I (the soul) can freely choose to use this energy in a variety of ways. If I choose to take in too many calories (energy units), then my body will store this energy as fat. It is available to me to use if I so choose. If I choose to not eat and do not take in any calories, then my body will eventually run out of energy and it will starve to death.

You are not the only one who has this incorrect view of the soul, Jason. In fact, some fairly intelligent individuals attack the same straw man. Brian Cox, a physicist, argued against “ghosts” (or souls) and made the same mistake. He asserted:

“I would say if there’s some kind of substance that’s driving our bodies, making my arms move and legs move, then it must interact with the particles out of which our bodies are made. And seeing as we’ve made high precision measurements of the ways that particles interact, then my assertion is there can be no such thing as an energy source that’s driving our bodies.”

If this is the best the naturalist has to offer then substance dualists are in good shape. Cox is attacking a view of the soul that no one is defending in the first place. As my friend Tim Reed said:

//The entire argument rests upon a premise that even substance dualists reject.//

Some might assert that it “takes energy to use energy” and point to my truck analogy above where I had to have my own energy to use the truck’s available energy. However, I believe a thought experiment can be offered demonstrating how an immaterial soul can indirectly move a material body without adding any energy to the mix. Since we are already discussing “ghosts,” invite some zombies to the party to help clarify!

Ghosts & Zombies

The arms of zombies move with energy available to them based on no beliefs OR beliefs that are not “up to” the zombie. With this in mind, if naturalism is true, then human beings are nothing more than glorified zombies because our thoughts are not up to us but physics, chemistry, and past events (humans are not responsible for these things). With that said, if naturalism is true, then human arms and legs move apart from a soul.

For the next step of the zombie thought experiment, suppose a freethinking immaterial soul was added to the zombie. The soul does not use or add energy (it is not composed of atoms nor does it burn calories); rather, it simply thinks freely and is free to choose some thoughts and beliefs — which are not composed of matter and do not weigh anything. With this in mind, the same energy that was already available to the zombie — and used apart from beliefs or apart from free thinking — can now be used for rational and intentional purposes based on the now “former zombie’s” free thinking.

That is to say, our bodies either move based upon our thoughts and beliefs OR our bodies move un-rationally! So, the soul does not directly move arms (or physical bodies), but it simply freely thinks and our bodies “use” the available energy by reacting and moving according to our free thoughts which form our beliefs. 

To make sure I understood my science correctly I discussed this topic with several scientists in different fields (biology, chemistry, and physics). The following was one of their responses:

Brain function requires energy and on naturalism, any process using the brain would seem to require energy (including decision making processes).  I would not think adding free will into that equation should change anything (i.e., it should take no more energy to think freely than to only follow instinct.)

To clarify: if naturalism is true, our thoughts are not up to us and as Sam Harris says, “we are not responsible for them.” Thus, if our actions follow from our thoughts (which are not up to us), then our actions are not “up to us” either. However, if a non-physical soul is free from the laws of physics, then it seems it would be free to think. This free thinking would be “up to us,” but that is the only thing that changes. The soul is not an “energy source” on this view. The body simply reacts to thoughts and beliefs just as it does on naturalism. If thoughts and beliefs are not up to us, then the actions of our bodies are not up to us. If thoughts and beliefs are (at least some of the time) up to us, then at least some of the movements of our bodies are up to us (at least indirectly).

Bottom line: If naturalism is true, we have beliefs (determined by nature) and our bodies use energy to act according to those beliefs. On substance dualism nothing changes physically. The only difference is that not all of our beliefs are causally determined by nature (some of them are up to us). Thus, our bodies would still act according to those beliefs that were up to us and not up to physics and chemistry.


Substance dualism makes great sense of all the data (scientific, philosophical, historical, testimonial). With that said, however, I am willing to consider other options. I am open to the idea of  ontological idealism — the view that matter does not really exist. After all, some scientific experiments suggest that space and matter might be illusory. It follows from this that it is possible matter does not exist (if matter does not exist, then brains do not exist). However, it is impossible to deny that you are thinking about idealism right now! Thus, it is impossible for thoughts not to exist, but it is possible that your brain does not exist. Theistic idealism would follow and so would human souls.

Moreover, even if the immaterial soul were somehow proven not to exist it would be no deal breaker for Christianity. There are some Christian philosophers who hold a purely physicalist view of humanity like Peter van Inwagen and Nancey Murphy. I respect these Christian philosophers, but disagree with them on this issue. I think there is great reason to think immaterial free-thinking things (souls) exist.

Stay reasonable (Philippians 4:5),

Tim Stratton


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About the Author



(The FreeThinking Theist)

Tim pursued his undergraduate studies at the University of Nebraska-Kearney (B.A. 1997) and after working in full-time ministry for several years went on to attain his graduate degree from Biola University (M.A. 2014). Tim was recently accepted at North West University to pursue his Ph.D. in systematic theology with a focus on metaphysics.

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