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Criticisms of Cartesian Dualism


Four Key Criticisms

  1. Incoherence of interactionism

  2. Violation of the law of the conservation of energy

  3. Neural dependence

  4. Free will

About Dualism

Dualism is a belief that has existed since the earliest of times.

It began with the Egyptians, who introduced this idea of spirituality, afterlife and gods. The concept has grown and is still one widely accepted today in religious cultures.

The Christian belief is that God 'animates' us within the womb, gives us our soul.

But the concept we're dealing with is that put forward by a Mr. Rene Descartes.

Descartes theory is that the mind exists independently of the brain and the body. It takes up no physical space, it is unextended while the body is extended.

This is a hugely important theory when discussing the free will vs determinism debate, for it would be argued that it is our minds, which are independent of and therefore unaffected by the physical causal chain of events, that give us free will. Determinists argue that humans are made up of particles just as books and pens and lamps and stereos are (yes, I'm naming things from my desk) and so we are bound by the laws of nature and our actions are determined by immediately preceding events. But dualists claim that there is more to us than just subject matter, we have minds as well as bodies, we have free will!

It all sounds very nice. But as you've probably figured by now, it's not as ideal as it may seem. The theory of dualism runs into some pretty philosophically convincing criticisms.


How it works

Descartes believed that our minds worked in this way: our senses interacted with the brain, and the brain interacted with the mind, and vice versa. Since the mind was free from the physical realm, its choices were uninfluenced, giving us free will.

But it's not that simple.

Criticism 1

Incoherence of interactionism

If the mind is separate from the brain we cannot understand how they could interact because there is a gap in between. Moreover, if the mind is not part of the physical realm it doesn't make sense to say that it can cause the events of something physical. This is impossible.

According to the dualist, the mind and the brain are both two very different things, so where's the common language between them? How do they communicate if they are both so different and detached from each other? Descartes has some explaining to do...


Criticism 2

Violation of the law of the conservation of energy

Lets, for arguments sake, say the mind can effectively and efficiently communicate with the brain despite its differences. Where is the energy for the interaction coming from? The dualism theory violates the law of the conservation of energy, which is the scientific affirmation that energy can be neither created nor destroyed, it is a closed system. Or at least it has been up until this intrusion of the mind! For this mind to make any impact on the physical world, it must either be introducing new energy from this mysterious other-worldly plain that it lives on, or taking energy away from the physical world to use for itself. But energy is transferred, it can't be simply added or removed. So the mind has no energy to work from.

Criticism 3

Neural dependence

If our minds are not part of the physical plain, or part of this determinst theory of the causal chain of events, why then, does it not continue to work if say... we take a blow to the head. Minds shouldn't be affected by physical happenings if they exist independently, so why don't we carry on thinking when we're knocked unconscious?

You could say that it does I suppose. There is growing evidence to show thought processes from people in a coma. But that evidence is gained through examining the brain. The physical, real, tangible brain. Not the mind.

Perhaps then, the dualist could argue that the mind is closely, intricately linked with the brain. But that's basically just admitting that it is affected by the physical, and therefore dependent, which undermines the entire theory.

Criticism 4

Free will

So you've read all the criticisms, you know exactly why dualism is incredibly hard to explain. But just humour me for a moment. Lets just say you still believe in dualism okay? Okay. The mind is independent of the brain an body. We make our decisions completely freely and without influence. But now our body has to act on those decisions. And that body is part of the physical realm.


We've hit a wall.

Even if, after all this criticizing, we can still say with some conviction that dualism is legitimate, it can't give us free will. We're still stuck in the physical world, our body has limits, we can't act on every decision we make.


Most dualism is in cooperation with religion. Most dualism relies on the existence of a god. But this god already knows what actions we are going to perform before we perform them. So does that not imply they're already determined?

Maybe we're not free after all...

Or does God's omniscience make him exist independently of time and therefore able to see our actions as if they've already happened, giving us free will?

Or does God's omniscience make him exist independently of time and therefore able to see our actions as if they've already happened, giving us free will?


Well, I'll leave that up to you.

If you have any counter criticisms, if you have anything to add, if you have any claims to make, make them in the comments below.

I look forward to discussion.


snakeappletree on January 19, 2017:

Criticism 1 fails here: "Moreover, if the mind is not part of the physical realm it doesn't make sense to say that it can cause the events of something physical. This is impossible. " How is that impossible? It is not provable to be possible nor impossible. Therefore you cannot regard it as fact. It is one working assumption. Descarte was using the opposite working assumption.

Criticism 2 fails here: Bedini SG motor. This easy to build invention proves that the second law of thermodynamics is not a constant law because there are exceptions to it.

Criticism 3 fails here: If I tip a cup of water upside down the water falls out. This does not mean the cup is never going to be able to hold water again. This criticism denies such a things as dreams, telepathy and spirit mediums - none of which are measured by material science. This is why material science denies they exist. I have never been to Australia but I do not deny that it possibly exists.

Criticism 4 fails here: It is possible to remotely operate your computer. If you switch off your computer it cannot be remotely operated. If you switch on your computer but do not access the internet, does the internet cease to exist? Imagine the Mind to be something like that. Making statements that a thing is impossible because of ... and then restricting the possibilities to less-than-the-actual-possibilities does not make the thing impossible.

Keltor on December 05, 2016:

Hey, I know this is quite an older post, but hopefully you won't mind comments. I just found your YouTube channel and am quite impressed by both your musical ability, and (after following a random link from the comments section) your logical abilities. I do have one thing to add in support of dualism and it's that we're experiencing this life. Based on the observable world alone, we are all just complex machines that could run by themselves. Why are we seeing through these eyes then? Why are we experiencing this life. Please allow me to use this viewing of our world as a definition of consciousness. We are conscious. We have a consciousness. But there's no reason we should. One other thing I might add is that you cannot prove that anyone else is has a consciousness. You can prove that they exist and are going through the motions of life but you cannot prove that there is an actual viewing behind that lens as there is behind your own eyes. Let me know what you think and I'll continue with my video game analogy.

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