The Most Powerful Evidential Argument Against God?

In previous posts, I’ve been critical of an interview with Dr. Alvin Plantinga that was published in the Opinionator at the NYT a few weeks ago. He and the interviewer, both Christians, seem to suggest something that I think couldn’t be farther from the truth, namely, that atheists like Richard Dawkins and Bertrand Russell as well as other philosophers appeal to little or no evidence for the nonexistence of God thereby limiting them to the lesser epistemic claim of agnosticism. In fact, there is a variety of evidence that makes more sense on naturalism (the idea that no God or no entities like God exist) than on theism. While Plantinga did mention the evidential problem of evil (POE), I’d like to present two other evidential arguments that, ironically, Russell and Dawkins actually have made in the past, albeit not as explicitly as I will attempt here.

We are regularly told that the Christian God is maximally loving and that he therefore wants to have a loving relationship with each of us. A person cannot have a genuine relationship with someone in whose existence she doesn’t believe or actively denies. It should be no surprise then, that the Christian bible itself (1 Timothy 2:4) tells us that God wants everybody to know the truth of the gospel message which entails the knowledge of his loving existence.

Furthermore, many Christians believe that without a relationship with Christ, one is eternally damned. A maximally loving God would want us all to be saved, representing another reason for him to want us to have such a relationship with him.

Omnipotent God could easily provide causally sufficient evidence or a convincing religious experience so that everybody would know the truth of the gospel message.

This leads us to premise 1: if the Christian God were to exist, there would not be many (any?) nonbelievers in the world.

But there’s the rub. There are many people who do not believe in the Christian God in the world (premise 2).

Premise 2 is not only true today; one must also consider the billions of nonbelievers throughout history. The evidence of nonbelief is overwhelming and unquestionable.

Conclusion: The Christian God probably doesn’t exist.

This argument will work for any formulation of God where he is omnipotent and maximally loving – a God that I’m sure Plantinga and Gutting accept. If belief in such a God is required to avoid eternal damnation, so much the better for the argument from nonbelief (ANB).

The work of the ANB is done in premise 1. If you’re thinking that God’s reason for permitting the existence of so many nonbelievers has something to do with preserving our free will, I think that you’re demonstrably wrong. If I wanted to enter into a loving relationship with Christy Turlington, making her clearly aware of my existence would have no influence upon her complete freedom to reciprocate or (more likely!) to avoid doing so. Making people aware of facts doesn’t influence their choices if indeed they are free, and if the existence of the Christian God is a fact, he could easily make it well known to us all.

Notice that if naturalism is true, the problem of nonbelief just isn’t a problem at all. People throughout history have believed a dizzying array of false things about the nature of their world for which we can “thank” all kinds of natural conditions such as our often-unreliable cognitive faculties.

Stephen Maitzen, a Canadian philosopher argues that the following related problem is an even greater challenge for the Christian theist to explain: why is it that about 93% of Mexicans believe in the Christian God, but about 93% of Indians do not? Why do nearly all citizens of Iran, Cambodia, Laos, and Burma not believe in the Christian God (most people in the latter 3 countries don't believe in any god), while most Americans and Italians do? While the ANB asks why the Christian God permits so many people to not believe, the argument from the demographics of Christian theism (ADT) asks why he tolerates such a skewed distribution of nonbelief. If the Christian God doesn’t exist, the geographic clustering of nonbelief is easily explained by messy and haphazard human influences like culture and politics.

Christian responses to these problems often suggest that all non-believers are morally or epistemically defective and therefore blameworthy for their nonbelief. God has done all that he can and their failure to believe is their own.  Consider what this proposition entails carefully: billions upon billions of non-believers who have ever lived or are alive today are all blameworthy for their unbelief. If even one person has genuinely sought God and remained bewildered about his existence, the ANB runs through, and the Christian God probably doesn’t exist. It seems that Mother Teresa may well have been just such a person. There was a time in my younger life when I lived in a tentatively Christian family and studied at Christian schools and I genuinely sought God and heard and felt nothing in return.

Apart from frank implausibility, there are a few other problems with this line of reasoning. The claim that one's unbelieving brethren  - people like me - are somehow morally or epistemically defective is also completely ad hoc: one has no reason to believe it except that it permits one to escape the problems with belief that I’ve outlined above. Furthermore, if one assumes that all nonbelievers must be blameworthy, then one's reasoning is circular. And even if one found these types of responses plausible and fitting, what they cannot do is explain why non-belief is so geographically clustered. Even if one thought that all nonbelievers are morally or epistemically defective, what moral, epistemic, or other defect in people clusters geographically in this extreme way? None.

I believe that this argument has been made before (though clearly not as explicitly as I have tried to summarize here based on the work of J.L. Schellenberg, Theodore M. Drange, and Stephen Maitzen) by other atheists including ones that Plantinga criticized for failing to appeal to sufficient evidence to support atheism over agnosticism. Recall the ending of the Bertrand Russell quote that Plantinga referred to:

“I cannot, therefore, think it presumptuous to doubt something which has long been held to be true, especially when this opinion has only prevailed in certain geographical regions, as is the case with all theological opinions.”

And watch the first couple of minutes of this video of Richard Dawkins:

Is there any doubt that the vast numbers of nonbelievers and especially their skewed geographical distribution count as evidence against Christian theism and in favor of naturalism? I can’t see any. There is other evidence and there are other arguments against Christian theism, but Plantinga and Gutting seem to want you to believe the contrary. If you’re a Christian, I encourage you to be skeptical of their suggestion and look more deeply into it.

In the meantime, do you have a reasonable doubt about either the argument from nonbelief or (especially!) the argument from the demographics of theism? If so, I’d love to hear what it is. Spell it out for me and challenge my beliefs. I don’t want to be wrong for a second longer than I have to. If you don’t, then I’m afraid that you have no reasonable doubt that the Christian God (at least as described above) does not exist.

What doctors and anti-vaxxers have in common: Part 2

When I openly pose the post-vaccine fever scenario, most people consider it more likely than not that the vaccine caused the fever. That is, most people think the chance that the vaccine caused the fever is > 50%. Almost every medical student in a group of 20 that I was teaching a few weeks ago thought that. After all, fever is a well-recognized side effect of vaccine injections and your child was perfectly fine until a few days after the injection. Who wouldn’t reasonably conclude that the vaccine likely caused the fever?

Notice that by focusing responses on 1-49%, I set the question up to give you a better chance at being correct than they were but still, nobody got the question right. Don't worry. You are in good company. For now, just remember the feeling you had when you made your choice.

Back in the 80’s, investigators were concerned that combining mumps, measles, and rubella vaccines into one (MMR) might increase the risk of side effects, so some doctors in Finland did an ingenious study to determine what was not just temporally associated with vaccine injection, but caused by vaccine injection.

They studied 581 pairs of twins and randomly gave the MMR injection to one of the twins and a placebo injection to the other. Then, so as to not deprive the children that got a placebo injection of the vaccine's proven benefits, three weeks later, they gave each twin the opposite of what they had earlier received. Parents, who were blinded (they didn’t know when the kids were getting the placebo or the MMR injection), were instructed to vigilantly check for fever and a variety of other potential side effects after each injection.

In the first 6 days after placebo injection, 17% of children had a fever. That’s the background frequency of fever in vaccine-age children, and it's pretty high, huh? On the other hand, in the first 6 days after MMR injection, 17.2% of children got a fever. The difference - 0.2% - is what can be causally attributed to the active ingredients in the vaccine.

Conclusion: >99% of fevers that occur in the first week after MMR injection have nothing to do with the vaccine at all. 

However, we are very likely to erroneously attribute the fever to the vaccine. We do this because we have a powerful intuition that leads us to identify a causal relationship when 2 events that could possibly be causally related follow each other in time. We are mistaking what is merely possible for what is probable. Unfortunately, children develop mysterious illnesses like MS, autism, epilepsy, hepatitis, arthritis, etc. with regular frequency. Sometimes, those illnesses will appear fairly soon after getting a vaccination, and that’s when that intuition of ours can do some serious damage. That same intuition does damage when mysterious conditions like these disappear -as they often spontaneously do- after interventions that have no effect on the disease like prayer, acupuncture, chiropractic neck manipulations, homeopathic remedies, etc. Only randomized controlled trials can sort this stuff out.

Imagine once again your son who got a fever early after the MMR injection, only now, he is a healthy 18-year-old man who was spared the ravages of mumps, measles, and rubella. At any point in his upbringing, would you have ever had cause to stop and be thankful for the vaccine? How could you? You’d have had no way of knowing whether your child would have contracted one of these illness had he not been vaccinated!

See what’s happening here? The way that we experience life offers us no way to identify the situation where a vaccine prevents a horrible illness or death. On the other hand, we have a tendency to erroneously attribute adverse events to vaccines when they follow each other in time. Remember how you felt about your child's fever after MMR vaccine? Parents considering whether to vaccinate their children can anticipate the regret that they will experience if their child does develop an illness like autism afterwards, but they cannot anticipate the relief that they cannot experience when their child is spared a vaccine-preventable illness. Anti-vaxxers are much more likely to anticipate the former type of regret than the latter because they tend to overestimate the risks of vaccines and underestimate their benefits. Our intuitions erroneously set vaccines up to be unattractive. 

And so it is with physicians and oral anticoagulants (OAC’s). Bleeding events are fairly common. Whenever somebody experiences a bleeding event on an OAC, they and the doctors tasked with treating the bleeding blame the OAC. The reality is that most bleeding events that happen while on an OAC would have happened otherwise: just as only 0.2% of fevers early after the MMR injection were caused by it, only 0.2-0.3% of bleeds /yr are caused by the OAC. But physicians can anticipate the regret that they will experience when they prescribe an OAC to a person with atrial fibrillation (AF) who then develops a bleeding event. The finger of blame will point to the OAC and the physician who prescribed it. Unfortunately, nobody ever returns to the prescribing physician to pat them on the back and thank them for the stroke that they and the OAC prevented because, just like the case of mumps that your son avoided, there is no way to recognize a stroke that would otherwise have happened. Doctors' intuitions erroneously set OACs up to be unattractive.

Just as there is evidence that anti-vaxxers overestimate the risk of vaccines, so is there evidence that physicians overestimate the risks of OACs, exaggerating  their anticipated regret over prescribing one.

Our ancestors evolved on an African Savannah with no pressures to select for intuitions that address the types of complicated primary prevention questions posed by vaccination and OAC use in AF. It seems that we did evolve intuitions that lead us to readily identify patterns and infer causal relations where there often isn't one. On the whole, this rudimentary heuristic has done well to protect us from certain kinds of dangers, but, as Sam Harris has written, “we have flown the perch built for us by evolution”. If we are to make advances with complex questions, we simply have to recognize when our intuitions lead us astray, and they regularly do, whether we are specialized physicians or lay people. None of us are spared the consequences of irrationality. It is a struggle we all must recognize and participate in.

If you are faced with complex decisions like vaccinating or taking an OAC, I hope that you are most heavily weighing the evidence from RCTs. If you aren't, then I hope that you are seeking the involvement of people who are. Otherwise, you're just being irrational.

What doctors and anti-vaxxers have in common: Part 1

A few years ago, a Canadian neurologist reviewed the case of every patient admitted to 12 Ontario hospitals  with a stroke between 2003 and 2007. He only studied patients with a heart rhythm disorder called atrial fibrillation (AF) because AF is known to cause blood clots inside the heart that can get pumped out and block a brain artery causing strokes. There is an abundance of clear evidence: people who suffer from AF can dramatically reduce their risk of stroke by taking oral anticoagulants (OACs) that prevent intracardiac clots from forming. These medications are to be avoided in people with bleeding problems, but otherwise, the majority of people with AF ought to take one.

Gladstone discovered something shocking: after excluding patients with bleeding risks, only 40% of people with AF who suffered a stroke were on an OAC when all of them ought to have been, and three quarters of them were under-treated. The data was even more staggering for patients with AF who were admitted with their second stroke – a situation where it ought to be blatantly obvious that an OAC is needed: only 57% of people were being treated and two thirds of them were undertreated. Overall, only about 15% of patients with AF were appropriately treated with an OAC. The conclusion was sobering: if these patients had been appropriately treated, the majority of these strokes could have been prevented.

Of course, part of the responsibility for not being on OACs rests with patients who decide not to take one, but this is one study among many that indicate that physicians around the world routinely under-prescribe OACs to people with AF. Is it because AF is rare and doctors just don’t know about the opportunity to prevent strokes by prescribing OACs? Consider that AF is the most common arrhythmia in adults and that you and everybody you know and love has a 1 in 4 chance of developing it at some point in life. Plus, it’s responsible for 20% of all strokes. Is it because the risks and benefits are unclear? Absolutely not: as I mentioned earlier, over 10 randomized trials done around the world by different investigators involving thousands of patients have all shown the same consistent results: at the cost of a small (0.3%/yr)increase in the risk of bleeding, OACs reduce the risk of stroke by around 65%.

So why are doctors not doing the obvious and prescribing these drugs?

What's the anti-OAC body count at today?

In my next blog entry, I’ll explain the situation, but first, I want you to consider the following common scenario: 

You have a young child who has been perfectly well until he receives a combined vaccine injection for mumps, measles, and rubella (MMR). Around 3-6 days after the shot, your son develops some irritability and he feels hot; his temperature is 38.9 degrees C. You give him some acetaminophen and in an hour, he defervesces and perks up. How likely do you think it is that the vaccine injection caused his fever?

(A) > 50%
(B) 31-50%
(C) 21-30%
(D) 11-20%
(E) 1-10%
(F) < 1%?

Don't Google it. Close your eyes and visualize the situation and try to be as honest as you can. You and your spouse are probably going to bring this very question up when the fever develops. What are you going to say? Tell us by anonymously voting in the poll on the right. (Poll now down.)

(Go to Part 2, and the answer)

New Guidelines for Managing Valvular Heart Disease Are Out

The new ACC/AHA Guidelines for Valvular Heart Disease are just out:

It seems that I am on the cusp of periodic surveillance and a Class IIb indication for elective valve replacement.

How to Want to Change Your Mind

The incomparable Julia Galef with what I think is some great epistemic advice.

What big ideas have you changed your mind about?

News about my health

About a year ago, my second child was two, and while what I had was adequate, I decided to get some additional term life insurance since it’s still relatively cheap for the young and healthy. You never know.

Then a nurse who visited my home as part of the underwriting process recorded my BP at 150/60.

What? My BP had always been around 115/60-70.

She wasn’t that hot.

“Relax,” she said, “lie down and relax and we’ll take it again.” The trouble was, since I had had nothing to worry about, I had been relaxed, though after that reading, not so much.

We eventually were able to get a couple of readings at 130/50, and the rest of the interview and exam went well even though I was a little distracted by the high systolic BP and relatively low diastolic BP. As a cardiologist, I got to thinking about a heart valve problem that can cause that precise BP pattern: aortic valve regurgitation (leaking). I got out a stethoscope, and along with the first beat I heard when I put it on my chest, there was a harsh, loud systolic murmur accompanied by a loud diastolic murmur.

“Where did that come from?”

I kept listening, beat after beat, wondering if what I was hearing was for real, but it didn’t go away.

Fuuuuck. (Sorry for the technical doctor-talk)

The office right next to mine at Foothills Hospital is occupied by a supremely talented and bright cardiologist with expertise in heart imaging. She arranged an ultrasound and MRI: aortic regurgitation (AR) is graded as mild, moderate, or severe, and mine was severe. Boom.

The other thing we learned was that this had been going on for at least several years since the extra blood volume rushing back into my heart had caused it to enlarge.

Severely.

Buh-oom.

The good (?) news was that my heart pumping function was still normal, everything else looked fine, and I had no symptoms. In fact, I had trained and run my first 10k race about 6 months earlier and had been running 5k every morning in Maui just a couple of weeks earlier. I wasn’t in the best shape of my life, but I felt pretty darn good.

Questions arose and played a rather constant game of musical chairs for a seat in my consciousness. How had I not noticed this before? Why was my valve leaking? Why me? Can my kids get this? Will I live to see 50? 60? 70? Tomorrow? And of most concern, because AR is a mechanical problem that requires a mechanical solution, namely valve surgery, when would I need to have mine?

There was an easy answer to the first question. Aortic regurgitation can progress slowly over time and the heart compensates by enlarging to accommodate the blood that leaks back with each beat. The net forward blood flow remains normal, so symptoms are rare until it’s been around for a long time. As a cardiology resident in my twenties learning how to do and interpret heart ultrasounds, I had done several on myself and my aortic valve was normal then, so this had to have developed sometime in the past 20 years. Diastolic murmurs are rare and challenging to hear, so it’s no surprise that my GP hadn’t picked up on it despite annual or biannual check-ups that I’d been having since I was 40.

There is a list of well-recognized causes of AR. The most common culprits for a young person include a previous infection that affects the valve, being born with a bicuspid aortic valve (which is a valve with 2 leaflets instead of the usual 3), or dilatation of the aorta so that the leaflets stretch apart and no longer touch in the center. None applied to me. To this day, the cause remains unknown.

Timing of surgery in severe AR is a question that doesn’t have a clear answer either. Thankfully, there are reasonable ones. The concern is this: as the heart enlarges to compensate, there reaches a point where irreversible heart dysfunction begins to develop. The enlarged heart can become weak, not squeeze well, and if left long enough, that may be permanent. One might ask, why not operate right away in that case, so as to not permit the mistake of waiting too long to occur. Unfortunately, the surgical procedure and options are far from perfect. The operation itself has a risk of death that approximates 1%, and the best solution is to replace the leaking valve with either a pig valve or a mechanical one. Pig valves don’t often last > 10 years in young people, so once the first surgery is done, a clock starts counting down to the timing of the next valve replacement operation. A mechanical valve is likely to last for many decades, but the foreign material is prone to blood clots that can cause life-threatening valve blockage, or, if the clots break free and get pumped into and block a brain artery, stroke. Oral anticoagulants (OAC) are forever required to prevent these clot-related complications, and they increase the risk of bleeding, which, while small, builds up over the years. Have a car accident on OACs and serious bleeding can turn fatal. Bang your head on OACs and a goose egg can turn into a coma like the one Michael Schumacher has been in for over 2 months. So there are a number of good reasons to try to put off valve surgery as long as possible.

Back in the 80's & 90’s, there were even better reasons to put off valve surgery: the risks of the operation were considerably higher then. Not knowing when the optimal time to intervene and best preserve longevity and heart function, cardiologists made the decision to operate when the patient developed symptoms like shortness of breath, weakness, fatigue, and exercise intolerance. Thanks to several groups who performed careful long term follow up of consecutive patients with AR and reported their results in medical journals, some patterns began to emerge. As long as valve replacement occurred before the heart dilated beyond 55 mm during a contraction, or beyond 75 mm during relaxation, and before the pumping function had dropped below 50% (normal = >55%), nearly all patients had normal heart function after surgery. The latest guidelines recommending these cutoff values for valve replacement have been around since 2006, and updated ones are due any day now. My heart pumping function was 53-55% and my heart measurements were 43 mm and 63-65 mm respectively, so I hadn’t reached the cut-off values yet.

Still, the opinions of my cardiologist and others who had been involved in imaging my heart were mixed. While they agreed that surgery wasn’t urgently required, some advised making plans to operate within 6-12 months while others suggested waiting and watching the measurements with repeat ultrasounds every 6 months. My initial inclination was also to get a new valve sooner rather than later. I just didn’t like the idea of having the leak and knowing that it was causing loading conditions that were slowly changing the number, size and function of my heart cells. I was, after all, getting close to the cut off values anyway.

An ultrasound done 3 months later showed no changes, so we knew we weren’t dealing with a rapidly progressive process.  Long story short, I just had my one-year follow up ultrasound and it looks exactly the same. While the first 6 months after diagnosis were pretty stressful, all those circulating questions started slowly receding and I found myself gradually able to return to thinking about the usual kinds of things that I think about, including making plans for the future. Those were all put on hold for a while. My appetite returned to normal, but my diet improved. I kept exercising aerobically and feeling well. I made a lot less Lego.

Life is pretty much back to normal now, except for that common cliché that certainly applies to me: everyday, I wake up and feel lucky. There is an equalizing comfort in the knowledge that all that anybody has is this precious present.

I’ve seen a world class valve disease expert who is the lead author of the updated joint American College of Cardiology and American Heart Association valve disease guidelines. He’s followed many patients like me for decades, and he tells me that I may be able to avoid surgery for years. In the meantime, I’ll get ultrasounds every 6 months to carefully watch for any changes, and I’ll hope that more durable tissue valves, or more clot-resistant mechanical valves, or better OACs get developed. It’s pretty much business as usual again in our house.

I find myself wanting to share this experience with others, and wanting to keep a record of some of the things that are important to me as I move on. If the valve should somehow catch up with me sooner than expected, I like the idea of having a blog that my kids might be able to read and at least kind of know me by. That’s one of the hardest things to imagine, that I might die while my kids are too young to remember me, or to be influenced by me in a more-than-genetic way.

Remember that insurance that I applied for? Ironically, I was approved at a preferred rate for especially healthy and low risk clients. How d’ya like them apples?

Of course, I had to decline the insurance because of what I had discovered during the underwriting process, which is fine because I’m adequately insured anyway. If you have kids and you’re not, I strongly advise you to at least get some cheap term insurance while you can. Our bodies evolved on the African savannah over millions of years. There is no evidence of any intelligence in the design- only the pressures of reality selecting among random trial and error. That’s why we break down all the time. It’s amazing that I haven’t had any health issues until this and I hope that you’re all considerably luckier than that, but one shouldn’t count on it or take that risk with the well-being of one’s dependants. There is no magic keeping anybody safe. The sun rises and the rain falls equally upon us, so let's make sure that we have sunscreen and an umbrella.