In discussing lynching, David Deutsch says,
“But in the examples I gave, the genes are not just non-causal factors and the observed effects are not merely correlations. The genes in question are perfectly genuine, overwhelmingly significant, causes of the given effects. But only in one sense, not in another.”
Yes David, there is a difference between necessary and necessary and sufficient. And yes, some “causes” seem more important than others.

Thank you for clarifying that.

Genes are (for the most part) necessary for the formation of brains and hearts; and necessary for the evolution of diseases and people. Yes, genes are important, even necessary, but they are not necessary and sufficient for the evolution of people and their parts. You need the protoplasm stuff … and gravity and plants and food and a few other things, too –- even atoms and electrons help! Yes, the more you think about it, causation is a complicated concept when it comes to explaining things!

And yes , black people have a skin color which causes certain deranged white people to want to act very badly to those possessing this characteristic. And yes genes, in a causal chain, “cause” individuals to have a tendency to have black skin; so in a twisted sense, genes coding for the development of black skin can cause evil people to manifest their hostilities.

The only thing I can’t figure out is how this discussion of causality has anything at all to do with whether brain pathology causes serious mental illness?

Most people and virtually all physicians are comfortable with the concept that diabetes is a cause of heart disease. But if one doesn’t believe that diabetes causes heart disease, because diabetes is neither completely necessary nor completely sufficient to cause heart disease, then the discussion is effectively over. If one believes that only something that is completely necessary and completely sufficient can be said to “cause” something else in medicine, then one can say that there are no “causes” in medicine at all! There is literally nothing in medicine which causes anything so completely. So yes, if diabetes does not cause heart disease, then brain disease does not cause mental illness. But this argument is trivial.

David, you were discussing lynchings and the causes of the Holocaust to make the point that nothing in medicine can be said to completely cause something else? So Hitler was not the only cause of the Holocaust, smoking is not the only cause of cancer, major depression is not the exclusive cause of worsening heart disease, and brain disease is not the only cause of mental illness? With respect, it’s rather obvious that any given phenomenon in medicine (and life) has multiple causes. Don’t you think? Perhaps your point is different. Perhaps you think brain disease is not an important or relevant cause of mental illness, while diabetes is an important cause of heart disease. If so, on what basis do you choose to make this distinction? Your ”prejudice” should be explicitly stated.

But if you believe that diabetes is a relevant cause of heart disease, then you can also logically believe that brain disease is a relevant cause of mental illness, just as major depression is a relevant cause of heart disease progression (But none of these causes are “necessary and sufficient!”).

So the issue, then, is not really causality, the issue is evidence!

When Dr. Lieberman scans the brains of individuals with schizophrenia suffering their first psychotic break, in a double-blind experiment, and randomizes half to an ineffective treatment and half to an effective treatment, then watches the brains of the ineffectively treated shrink by 12 cc’s in 12 weeks; few but the most stubborn and simplistic philosophers would logically doubt that schizophrenia is a horribly destructive brain disease. When the head of the NIH says a first episode psychotic break damages the brain in the same (logical) way that a heart-attack damages the heart, he is referring to precisely this type of evidence. When these same patients with schizophrenia are followed for two years and their brains are (partially) protected by a medication and don’t shrink, and when in fact there is prelimianry evidence of neural regeneration, that is cause for hope.

Now, if we had known who was going to develop a first-episode psychotic break, and had premedicated them with this same medication, before their first full psychotic period; that is if we had medicated them during the “prodromal period”, would this intervention have completely prevented the subsequent brain damage?

That is a question worth asking. It is a good question, because a scientifically valid answer to it could prevent hardship, pain, and loss of life.

By the way, 12 cc’s is quite visible and Dr. Lieberman has created movie-like 3- dimensional images of the shrinking brains using serial brain scanning…..quite frightening since the changes are so easily and dramatically seen.

As for the reader who said the following,. “The World is arguing against the concept of mental illness, i.e., diseases of the mind. Such "diseases" do not have a physical cluster of symptoms, but are identified by behaviour e.g., Attention Deficit Hyperactivity Disorder, Depression, and (yes) Schizophrenia. Minds cannot be infected with diseases because the mind is not material.”

To my way of thinking, the concept of “material” may be a little less “physical” than you think and “mind” may be a bit more. But I am not going to be able to change your world-view. Your dualistic philosophy is apparently assumed and therefore not a scientific proposition. Let me just point out the odd logical conclusions of your stance.

One hundred years ago, grand-mal seizures were described as tonic then clonic contractions of the limbs, with lack of speaking, much drooling, and frequent incontinence. (Yes, ALL of these “symptoms” are “just” BEHAVIORS)

And one hundred years ago there were those, just like some of the readership of The World, who claimed that these seizures could not be “diseases” because the condition was not described as a “physical cluster of symptoms” (to quote the critic above), but rather the condition was defined by behavior (tonic clonic movement of limbs and such). Indeed, individuals with seizures were housed in psychiatric facilities (with the rest of the poor souls who didn’t have real “diseases”.) Yes, ideas do have consequences. Not only were the mentally ill mistreated, so were those with epilepsy!

I also want to point out to my critic above that given your conceptions, grand-mal seizure behaviors, and especially temporal lobe seizure behaviors, until relatively recently, were not thought of as manifestations of brain disease. Rather they were thought to be manifestations of decisions made by individuals or of an invasion of evil spirits into the body. Amazing how this “cluster” of “behaviors” became a disease in a few short years!! Between you and me, I bet grand mal epilepsy was a “disease” 100 years ago, just as it is today. What do you think?

Our minds allow us to organize events on various scales. We can look at the movement of muscle fiber in an arm on a molecular level (carbon compounds interacting with carbon compounds) we can look at the firing of neurons as they innervate an arm muscle (the physical “symptom” level, or we can watch the whole arm move as a consequence of its neuromuscular innervations.(i.e. we can watch the arms behavior) I’m not sure that one level is philisophically or scientifically superior to the other. We stimulate the occipital lobe of the brain, the person reports seeing colors. We stimulate the temporal lobes at key places, the person reports hearing things. We stimulate the motor cortex and limbs move. By any logical conception, stimulating the brain caused these BEHAVIORS, although as yet the mechanisms are not fully understood.

Would it not be odd if the brain (but no other organ in the body) could not malfunction and so cause inappropriate activation of particular brain areas, such that the initial visible manifestation of this brain malfunction was an observable “cluster of behaviors”. Just as diabetes (by as yet not completely known mechanisms) causes deterioration in those with coronary artery disease, brain malfunction (by as yet not completely known mechanisms) causes deterioration in behavior.

What very obvious “symptoms” would a malfunctioning brain present with, if not abnormal clusters of unusual behaviors, otherwise known as “mental illnesses”? The brain is the organ of behavior, so when it malfunctions in “mental illness”, the symptom clusters presented are behavioral in origin. To not believe in the existence of mental illness, one either has to believe that the brain cannot malfunction, or that the brain is not the organ of behavior!

And to my other critic (!?)
“There’s no diagnostic test (yea, basically correct)

“There’s no method of treatment”

…..No, that’s quite wrong. I would invite you (or anyone with good intentions) to come to the psychiatric hospital and witness dramatic and often remarkable changes in many (but not all) patients with schizophrenia and other mental illnesses, once treated. It would not take more than a few months of observation, and your preconceptions would just evaporate. It’s one thing to engage in fun philisophical speculation, and another to see things with your own eyes. …I told some of my patients and their family members about the remarkable conversations taking place on this web site. They gave me a quizzical look and then uniformly laughed (a gentle laugh) I think many writing for this web site could learn a lot from the mentally ill!

“There’s no known biological mechanism”
…Sort of. There’s also no known biological mechanism for most “diseases” including hypertension, diabetes, bipolar disease, etc. Perhaps one could reasonably argue that there are better biological explanations of diabetes than schizophrenia, but we’re still not doing so well in fully explaining (let alone defining) most medical illnesses, including diabetes. Unfortunately doctors are better treaters than diagnosticians. Just the way it is right now.

And….
“I’ll start taking such claims seriously when this ‘associated risk’ is demonstrated in a methodologically sound, prospective study based on prenatal or neonatal genetic sampling”

To the author K.W., how much money do you have? To my knowledge, such human studies have not been done for most diseases with known genetic precipitants and causes. Do you really believe that specific human genes are not involved in the formation of corneas, because nobody has done a “methodologically sound, prospective study based on prenatal or neonatal genetic sampling” to find the specific genes which code for the proteins that lead to the development of corneas?

Finally, thank you for giving me the opportunity to respond to those commenting on my comments.

Michael

By the way, it is truly an honor to correspond with David Deutsch in one of multiple universes. I’ve loved your writing and your books.