Monday, December 28, 2009

Search Judaism – A Critique: Chapter One, section four

This is a milestone for me. Two posts in one day! I've rarely had two posts in one week.

Where Dwells the Self? (Chapter One, section four)

Before I even begin to read this section, I would like to try to answer the heading’s question. The self, if we define it as one’s personality and ability to think and make decisions, dwells mostly in the pre-frontal cortex. Let’s see what the author’s answer is.

The author cites black holes as a phenomenon that we cannot observe directly but whose existence can be inferred from its effects. He asserts that black holes cannot be detected by “any instrument whatsoever” because their extremely high gravity keeps anything from escaping. This is not technically true, as Stephen Hawking showed in 1974 that black holes do emit a form of radiation (which was named ‘Hawking Radiation’). Still, his point that we can know about things we cannot detect directly by observing their effects is a valid one.
{incorrect scientific fact}

The author asks why it is that both people and animals ingest the same sorts of food and the same sort of nutrients travel to their brains, yet only humans produce art. He asks, “…the outcome is so different. Why?” The answer is that the structure and capabilities of the brains of various species are different. The implication that some metaphysical soul must be responsible for transforming the base nutrients into human experiences ignores this basic physiological fact.

He seems to be again trying to use art as evidence of a soul. This is a bad argument because art can be adequately explained by brain function without the need to posit a metaphysical soul.
{argument from ignorance, ignoring known explanations}

He goes on to list a number of things in what seems to be an attempt to show that our sense of self is separate from our physical bodies. It is true that we tend to think of ourselves as something other than our physical bodies. Our consciousness seems to dwell in an abstract mental landscape and most of us think of ourselves as existing somewhere behind our eyes. But here he is putting the cart before the horse. The concept of a soul probably developed because of our perception of ourselves as disembodied consciousness “driving” our bodies around like meaty vehicles. That we have this perception is in no way evidence that our consciousness is actually that disembodied soul.

Consciousness is most likely an emergent property of the brain. That we don’t perceive our thoughts, emotions, or sense of self as coming from the brain has no bearing on whether or not they actually originate within our skulls. Work with fMRI has consistently shown that various areas in the brain are responsible for emotion and cognition.

The author brings news stories and anecdotes to demonstrate that “we” are not our bodies – that is, we are not our limbs, heart, skin, etc. (More accurately, the anecdotes show that we don’t think of ourselves as our bodies.) Again, this is because we perceive ourselves as a consciousness driving the body around like a vehicle. That we think about ourselves this way is an interesting psychological phenomenon, but it doesn’t demonstrate that consciousness is caused by something separate from the body.

He now attempts to show that “we” are not seated in our brains.

First he asks if, theoretically, your memories and knowledge (and presumably personality, though he doesn’t mention that) could be transferred to another brain, would that become you, and would your old brain, wiped clean of your memories, still be you? I’m not sure what his point is exactly, but in such a case the old brain would cease to be you and the new brain would be you. This is because “you” – that is, your consciousness - is not the squishy grey matter in your skull, but is an emergent property of it. Much like the software that runs on a computer isn’t itself chips of etched silicon but is an emergent property of the information encoded on those chips.

Next he asserts that someone with complete retrograde amnesia (he merely says "amnesia," but to cite antegrade amnesia in this context makes no sense) still has a sense of self. I think he is trying to show that our memories are not our sense of self. Amnesiacs, however, do not lose all of their memories. They usually lose only certain types of memories and most sufferers retain knowledge of who they are. Further, retrograde amnesia is often more of a recall problem than damage to the memories themselves, so that an amnesiac's memories may still influence him even if he can't explicitly recall them. Even if it were the case that amnesiacs suffered complete loss of all memories yet retained their sense of self, this only shows that memory is not the only component of our self-identity.

There is a rare type of amnesia called dissociative amnesia where the sufferer does lose his sense of self, further disproving the author's claim. In such cases if the patient does not recall his former identity he will develop a new one. If, as the author claims, the sense of self is rooted in the soul, the change of self in patients with dissociative amnesia would imply that they switched souls. Yet I don’t think that is what he is trying to suggest.
{incorrect scientific fact}

The author then suggests that identical twins, who have the same DNA (and, he mistakenly thinks, identical brains), should have the same personality and interests if raised in the same environment. He claims that the fact that each twin has a unique sense of self shows that self is a property of the soul rather than the brain. This is a bad argument because: 1) Twin studies have shown that even when raised apart in different foster families, identical twins develop remarkably similar personalities and interests. This shows that biology has a profound effect on things that the author is claiming are products of the soul. 2) The differences that do exist between identical twins are caused by environmental differences. Siblings raised together do not have exactly identical experiences. Even in the womb, nutrient and hormone levels will vary slightly between the fetuses. Once born, differences in experiences early in life will produce differences in brain development; and in general throughout their lives different experiences will help shape their identities.
{incorrect scientific fact}

His next example is just silly. He asks if a clone, which has identical DNA to the person being cloned, will have a distinct sense of self or just be a copy of the original. Contrary to their portrayal in science fiction, in real life clones are just babies with one parent. Creating a clone is not like putting a paper in a copy machine and getting an exact duplicate. The clone, while genetically identical to the parent, will have different experiences and therefore a different sense of self.
{incorrect scientific fact}

The last two examples show a lack of understanding of how the brain develops. While biological predisposition has a large effect on brain development, so does experience. The experiences we have are literally hard-wired into our brains. Memories are encoded in neuronal connections, and therefore our experiences affect the physical structure of our brains.

He now quotes a number of scientists who assert that the self is separate from the brain without telling us why they think this is so. Granted, the book is not primarily about neuropsychology, but quoting opinions without providing actual evidence is an appeal to authority. I also have a suspicion that he is engaging in quote mining. A quick internet search of some of the scientists he quotes shows that their research does in fact support the mind being a property of the brain, making it very unlikely that the quotes used by the author mean what he implies they mean.

As an instance of a misleading quote, the author cites a “scientist, Dr. David Chalmers of Australian National University and director of the Centre for Consciousness.” Googling Dr. Chalmers’ name shows that he is not a nuero-scientist as the author implies, and is in fact not a scientist at all. He is a Professor of Philosophy. While philosophy is an intellectually stimulating and interesting field, it is not science, and therefore Dr. Chalmers’ philosophical opinions on the physical laws governing the mind-brain relationship carry no scientific weight. According to his biography, Dr. Chalmers is a proponent of dualism, but many of the arguments cited in the admittedly brief summary of his work seem to be appeals to ignorance. His is also a minority view, and many prominent scientists and philosophers have refuted his thesis.

The one bit of research the author does cite is an experiment where parts of the brain were subjected to electrical stimulation. The experimenter was able to elicit vivid memories from the subject, but the fact that the subject knew that these were memories and that electrical stimulation could not produce decisions were taken to mean that the sense of self is separate from the brain.

The first part is silly, as anyone can produce vivid memories of the past simply by closing their eyes and calling up the memories. Yet we always know that these experiences are memories. There is no reason to think that the experience of a memory triggered by artificially stimulating the brain would be any different than the experience of a memory evoked in the usual manner.

The second part is more interesting, but work with fMRI has shown that specific areas of the brain show increased activity when subjects are engaged in decision making, providing evidence that decision making is a function of the brain. The inability to produce decisions through electrical stimulation shows that we have an incomplete understanding of how the brain produces decisions, but that in itself does not show that there is a metaphysical component to the process. To claim such would be an argument from ignorance.
{incorrect scientific fact (x2), spin, appeal to authority, possible quote mining}

The author has failed to show that the soul exists, whether by inference or otherwise. That we can produce art is not evidence for the soul. That we perceive ourselves as separate from our bodies is not proof of the soul. That science doesn’t completely understand consciousness is not proof of the soul. At best, he has shown that we can’t completely rule out that the soul exists (if we define soul as a disembodied sense of self), but the burden of proof rests on the one making the positive claim to prove his claim is true, not on everyone else to prove the claim is false.


  1. So the soul is an illusion. Design in nature is an illusion. Perhaps everything we perceive in an illusion. The burden of proof lies on you to prove that we are not earthworms who are merely dreaming all this.

  2. So nice to see a comment from you in which you're civil.

    It is possible that everything we perceive is an illusion, but that is not the claim I’m making here. I’m addressing arguments for the existence of a particular metaphysical phenomenon, the soul. I’ve shown why each argument presented does not actually show the existence of a soul, and I’ve provided counterevidence that shows our experience is seated in our brains. It’s true that the failure of the arguments in the soul’s favor is not absolute proof that it doesn’t exist, but I’m not making an absolute claim. I’m just saying that, like everything else, the burden of proof is on the one making the positive claim.

    You’re statement that, “The burden of proof lies on you to prove that we are not earthworms who are merely dreaming all this,” is a strawman, as I never made that claim. Even if we were discussing extreme skepticism, I’m not sure you’re statement is true. That we accept empirical and inferential evidence as valid is a convenient convention. I don’t know that it’s possible to prove one way or another whether or not we’re really brains in a jar.