Thursday, July 21, 2011

Review of the Salem Witch Trials Argument

There's a review of my chapter contribution to The End of Christianity--the Salem Witch Trials argument here:

He argues that it is possible to consistently hold that they weren't witches at Salem, but Jesus really was resurrected.

Wednesday, July 20, 2011

Help: Trying to find a study

I'm going to crowd source this problem.  Recently I read a study of Americans, I think, that polled people about their attitudes on the one God/one path, many paths question.  They asked people whether they thought there were many paths to salvation or just one, more or less.  As I recall, Mormons and Jehovah's Witnesses turned out to be the most exclusive.  They were at the far end of the "one God/one path" scale.  I can't remember which denomination was at the other end of the scale.  I think the study came out within the last year or two, but I could be wrong about it.

Does this ring a bell for anyone?  Do you have the reference?  I need it!!



Thursday, July 7, 2011

Dead as a Doornail: Souls, Brains, and Survival

I recently submitted my contribution to an anthology on the survival of the soul, edited by Michael Martin and  Keith Augustine.  It's titled The Myth of the Afterlife:  Essays on the Case Against Life After Death, and it will be coming out on McFarland Press next year.  Here's a piece of my introductory chapter in it:

Polling shows that more than 70% of Americans believe in some form of life after death or the survival of the soul (Harris, 2009; PEW, 2008).  Many, probably most, of our depictions of the soul portray it as personally aware and with a consciousness that is essentially related to the embodied person.  Frequently, we describe the afterlife as someplace where a person, as a soul, is rewarded or punished or where their soul will serve or worship God.  Only a conscious, self-aware, thinking entity can do these things.  Furthermore, it is not merely that some consciousness or thinking entity survives the death of my body, but that my consciousness will survive.  My soul is my consciousness, so there will be continuity from my perspective between my awareness in my body and my awareness after the death of my body.  (How could the notions of reward or punishment in the afterlife make any sense without continuity?)  In our art, books, movies, mythology, and religious traditions, the transition from this life to the afterlife is often portrayed like the transition we make when we fall asleep and then wake up again.  When I wake up, I am the same person, with the same thoughts, memories, personal traits, and the same body as the person who went to sleep.  When I die, the soul leaves the body the difference is that when it wakes up, it has left the physical body behind and only the soul has survived with my thoughts, memories, and personal traits.  The common view is that something that makes me up will survive, that I will have eternal life, that I will be reincarnated, or my soul will go to heaven.   The things that are essential to me as an individual consciousness are my beliefs, my hopes, my dispositions, my emotional reactions, and my memories.  So in these popular depictions of the soul, we seem to be identifying it with what we usually call a person’s mind.   In what follows, then, we will treat “mind” and “soul” interchangeably.   
We are not here concerned with the non-personal accounts of the soul that portray it as something distinct from the physical body and that can exist autonomously from it, or that de-emphasize the conscious, personal aspects of the soul.  For example, we sometimes speak of there being an energy or life force in human beings, or that everyone possesses a part of some larger metaphysical entity or force.
The purpose of this introduction is to state the general evidence, particularly the empirical and inductive evidence, that the cessation of biological life also brings the end to a person’s mental life and hence the end of the soul.  What are the reasons we have for thinking that the experiences we associate with having a mind, thinking, remembering, or feeling stop when the life of the physical body stop? 
The competing views, therefore, are the extinction hypothesis—the view that absent some technological means of preservation or continuity that would sustain its functions, biological death marks the end of an individual’s mind.  The survival hypothesis is the view that some significant aspect of a person’s mental life—her consciousness, her thoughts, or her personality—persists beyond biological death. 
There is a strong probabilistic case for this simple argument for extinction:

1.   Human cognitive abilities, memories, personalities, thoughts, emotions, conscious awareness, and self-awareness (in short, the features we attribute to the personal soul) are dependent upon the brain to occur/exist. 
2.  The brain does not survive the death of the body.
3.  Therefore, the personal soul does not survive the death of the body.

The second premise is not controversial.  The evidence in favor of the first premise, then, is crucial to resolving the question of survival.  If the case for dependence is compelling, then we must accept the conclusion. 

II.  Neuroscientific Evidence for Dependence
Decades of evidence from stroke victims, motorcycle accidents, car wrecks, construction site accidents, fMRI scans, PET scans, brain imaging, and other medical studies have given us a detailed picture of which portions of the brain are active in conjunction with specific cognitive abilities and mental states.  What that research has shown is that minds depend upon brains.  Damaging a part of the brain destroys a part of our thoughts, eliminates a cognitive ability, or alters some personal or emotional capacity.  Restoring the electrical, chemical functions of the brain renews the mental function.    
While most of us would acknowledge some connection between mental function and the brain, we may have failed to see just how deep the connection runs.  Even the most abstract mental faculties and the most specific features and contents of our private, mental states can be mapped directly onto brain functions.  Some unusual brain disorders and the mental disruptions they cause illustrate the point.  People who suffer from Anton-Babinski syndrome are cortically blind, but they don’t believe or feel blind from their conscious perspective.  They will adamantly insist that they can see even in the face of clear evidence of their blindness.  They dismiss their inability to perform visual tasks by confabulating explanations.  Subjects with blind sight have the reverse problem; testing reveals that they can see, but they report no awareness of any visual stimuli.  They insist that they are blind even though they are not.  The syndrome results from a specific sort of damage to the occipital lobe of the brain.   
Capgras syndrome results from occipital temporal and frontal region lesions in the brain.   These patients have the powerful sense that someone they know, particularly a loved one, has been replaced by an imposter.  Vilayanur Ramachandran has postulated that the problem arises from a failure of the temporal cortex regions of the brain responsible for face recognition to communicate with limbic system regions responsible for emotional responses (1998).  Fregoli Delusion comes from a related form of brain damage that leads the patient to believe that many different people are actually one person with multiple disguises.  Cotard’s syndrome, or the delusional belief that you are dead, you don’t exist, or that you have lost your organs or blood results from damage to the interactions between the fusiform face area and the limbic system.  Patients with mirror prosopagnosia have difficulty processing the spatial relations of objects in a mirror with other objects in the area, and they often feel convinced that they are being followed.  Brain damage or congenital problems with the fusiform gyrus is responsible. 
What is important with these brain disorders is that we have mapped their specific locations or functional pathologies in the brain, sometimes down to the millimeter.  And the clear physical origin of the problem demonstrates the dependence of the mental capacity upon the brain.  The physical structures of the brain are causally responsible for consciousness and its capacities.  A neuroscientist examining scans of a stroke victim’s brain can now predict, sometimes with remarkable accuracy, exactly what sorts of cognitive, conceptual, emotional, or psychological problems with patient will experience as a result of their brain damage.  The connection is too direct, too pervasive, too immediate, and too strong to be ignored.  The physical foundation of mental functions shows that the alleged separation of mind from brain posited by the survival thesis cannot occur.  If a region of the brain is damaged or removed, then the correlated mental capacity goes, memory is lost, emotional affects are abbreviated, conceptual abilities disappear, or recognitional capacity will cease. 
In a remarkable study in 2005, neuroscientists reported the discovery of what they deemed the Halle Berry neuron.  In order to isolate the location of the electrical chaos that induced their epilepsy,  patients brains were implanted with electrodes.  Then the patient was shown a variety of pictures while the activity of the neurons in the vicinity of the probes was recorded.  In several instances, single neurons could be singled out whose activity spiked in response to specific images such as Halle Berry, Bill Clinton, or the Eiffel Tower.  One neuron fired when the subject looked at a picture of Halle Berry in an evening gown, in a cat woman suit, as a cartoon, and even the words “Halle Berry,” suggesting that the neuron played an integral role in a large web of neurons who were responsible for a variety of abstract and high level representations of Halle Berry rather than some simpler function such as edge discrimination.  This neuron did not respond comparably to the hundreds of other images used in the study (Quiroga, et al., 2005).  Again, the evidence is against the survival hypothesis; every aspect of a person’s mental function is produced by brain function. 
Research shows remarkable relationships between brain tumors and brain chemistry and bizarre thoughts or behaviors.  In one case, the onset of a patient’s hyper sexuality, obsession with porn, and pedophilia parallel’s the growth of a tumor in his right, orbitofrontal lobe.  When they removed the tumor, his urges lapsed.  A year later, when the tumor grew back, his pedophilia returned (Burns, Swerdlow, 2003)  The use of the Parkinson’s drug, pramipexole, has been shown to induce the sudden onset of compulsive behaviors like gambling, hyper sexuality, and overeating (Driver-Dunckley, et al., 2003).  Patients with no gambling history are overwhelmed with the urge to gamble when their dosages cross a particular threshold, and they gamble away their life savings.  Then when the dosage is reduced, the urge vanishes. 
The evidence from neuroscience shows that it is the proper functioning of the brain that makes even the most abstract cognitive abilities possible.  Stephen Pinker says,

If you send an electric current through the brain, you cause the person to have a vivid experience. If a part of the brain dies because of a blood clot or a burst artery or a bullet wound, a part of the person is gone -- the person may lose an ability to see, think, or feel in a certain way, and the entire personality may change. The same thing happens gradually when the brain accumulates a protein called beta-amyloid in the tragic disease known as Alzheimer's. The person -- the soul, if you want -- gradually disappears as the brain decays from this physical process  (2011)

When our brains are intact and healthy, we experience the full range of conscious and mental abilities that are attributed to the soul.  But when electrical, chemical, or structural functions of those regions of the brain are compromised, there is a direct, commensurate loss of those abilities. 
            To a less extreme degree, we can also see the physical foundations of the soul in our everyday lives without brain damage or electrical probes.  The physical dependence of mental states is evident when alterations of the chemistry of the brain with drugs, food, sleep-deprivation, fasting, or coffee change the way we think.  Brain chemistry affects the prevalence of positive or negative thoughts in our minds, our being irritable or happy, or our being cognitively impaired from too much alcohol to drink.  Too little to eat or drink and our thoughts grow slow and negative, too much caffeine and our thoughts race.  Even the weather seems to have a pronounced affect on the character and direction of our thoughts.   Hallucinogenic drugs induce visions in the mind of a different reality.  People on PCP often envision spiders and have a powerful belief that they can fly.  Millions of people take anti-depression drugs every day—chemical compounds that alter the chemical events in the brain—that produce a change in their beliefs, feelings, dispositions, and other mental states.  The causal dependence in these cases is clear; the mind depends upon specific chemical and electrical reactions in the nervous system.  Modify those reactions even slightly and there is a corresponding change in the mind and its contents.   Even something as common as a cup of espresso shows that those elements of consciousness that are alleged to survive biological death and depend directly upon the brain. 
If there was empirical evidence for survival, that is, if consciousness persists without the brain, then we would expect to find some exceptions to the close, direct correlations between the electro-chemical events in the brain and mental states, cognitive capacities, and conscious experience.  If there were cases where we could establish that some or all of the mind functions that we attribute to the soul occur in the absence of brain processes altogether, or in the absence of the particular brain processes that have been most closely correlated with those functions in other cases, then we would have some striking evidence for survival and against the first premise in our argument.  Suppose that we found cognitive abilities and consciousness to be present or absent with no apparent relation to the state of the human brain.  If brain damage of various sorts left cognitive functions unscathed, or if consciousness persisted despite alterations in brain chemistry and structure, then we might have some evidence to doubt the correlation and the causal connection.  Likewise, if some mental function lapsed while the brain was completely intact and functioning, we might have an empirical indicator of mind/brain autonomy.  But we find no such violations in either direction.