The Case for a Creator, Chapter 5

Chapter 5 is about the Big Bang and the cosmological argument, and we'll get to those. But I wanted to begin by highlighting an incredible, and telling, statement by Strobel in the opening paragraphs of the chapter.

It seemed to me that the beginning of everything was a good place to start my investigation into whether the affirmative evidence of science points toward or away from a Creator. At the time, I wasn't particularly interested in internal Christian debates over whether the world is young or old. The "when" wasn't as important to me as the "how"... [p.94]

The first bizarreness is that Strobel calls this an "internal Christian debate", as though only Christians were interested in how old the universe is, or as though only Christianity had the right to weigh in on that question.

But more importantly: Why on earth is Lee Strobel not interested in how old the world is? I thought this book was about science. And to quote Strobel himself from chapter 1:

"Science," said two-time Nobel Prize winner Linus Pauling, "is the search for the truth." [p.28]

Clearly, Strobel is not interested in "the search for the truth" - since he proclaims himself to be uninterested in one of the most important questions in cosmology - which means, by his own definition, that he's not really interested in doing science.

How can this intellectual incuriosity be reconciled with this book's stated purpose? Where is the bold, fearless exploration of cutting-edge scientific discoveries? Where are the interviews with the experts so they can give scintillating descriptions of the amazing truths that their research has uncovered? Why does Strobel suddenly decide he doesn't care what science has to say on just this one point?

If you're tuned in the politics of the ID movement, you already know why this is. It's part of the strategy concocted by ID's godfather, Philip Johnson, who wants to build a creationist "big tent" that includes both hardcore young-earth creationists and more moderate old-earth varieties. To this end, Johnson has consistently refused to take any stand on the age of the earth, so as to alienate none of his potential allies.

That's clearly the strategy Strobel is following here as well, which is why he treats this as a minor, irrelevant side issue, rather than one of the major and most significant discoveries in the entire field of cosmology, which it is. For the record: The universe is approximately 13.7 billion years old, as determined to high precision by probes like NASA's WMAP. This is not a triviality, but a momentous scientific discovery, and it's shameful how Strobel tries to dance around it.

But this episode shows something else important. For all that Strobel claims to be in favor of science, the truth is that he's only interested in science that supports what he believes. If science comes to conclusions that are politically inconvenient, he'll sweep them aside without a second thought. This is a lesson worth keeping in mind in later chapters.

Other posts in this series:

• Rebutting The Case for a Creator

The Case for a Creator, Chapter 2

Before embarking on his interviews, Strobel makes a statement about his investigative strategy:

In selecting these experts, I sought doctorate-level professors who have unquestioned expertise, are able to communicate in accessible language, and refuse to limit themselves only to the politically correct world of naturalism or materialism. After all, it wouldn't make sense to rule out any hypothesis at the outset. I wanted the freedom to pursue all possibilities. [p.28]

This is a favorite complaint of creationists, that scientists' insistence on natural hypotheses unfairly excludes whole classes of legitimate explanations. But in reality, the strict reliance on naturalism is not an arbitrary choice, but a necessary prerequisite for doing science.

At its most fundamental, science is a way of knowing, one that involves formulating testable hypotheses about the world and then checking to see if the evidence supports or disproves them. This is an incredibly productive strategy of undoubted power, one that in just a few hundred years has assembled a remarkably comprehensive picture of the world we live in and has given us tremendous power to shape that world in accordance with our desires.

The key to science is testability, or alternatively, falsifiability. We need to formulate our hypotheses so that they can be definitively put to the test. That way, we can winnow true ideas from false ones and gradually close in on the way reality truly works. If we had no way to do this, we would be stuck with an endless horde of competing ideas and no way to choose between them, and scientific progress would be impossible. (Readers will note that this is also a good description of the situation that does in fact exist among the world's religions.)

But what Strobel and his crew advocate is the inclusion of supernaturalism in science, in the form of an all-powerful creator whose motivations are unknowable and who can violate natural laws at arbitrary times and places to achieve his purposes. Clearly, this hypothesis is not one that can be tested in any meaningful way. In fact, it would foreclose scientific progress altogether by forcing us to always consider that the results of any test might be due to supernatural intervention.

Those who advocate a non-natural science never explain to the rest of us what that would look like. In fact, they don't seem to have any clear idea of it themselves. When the Templeton Foundation, which promotes conciliation between religion and science, offered funding to the advocates of intelligent design to test their ideas, they received no research proposals - a clear measure of the creationists' true devotion to scientific inquiry.

This is not to say that science conclusively disproves the supernatural. In principle, science can never totally rule out a supernatural explanation, precisely because they are not testable. But for the same reason, science cannot provide evidence for such explanations - unless they're formulated so that they can be either proved or disproved. For obvious reasons, creationists are mightily reluctant to offer hypotheses that can be put to the test.

Other posts in this series:

• Rebutting The Case for a Creator

The reliability of eyewitness accounts is one of the bedrock beliefs of our society. In ancient cultures - and in some modern cultures that still follow ancient laws - some crimes could only be proven by eyewitness testimonies. One of the most infamous examples was Pakistan's Hudood Ordinances, which mandated that allegations of rape could only be proven by four eyewitness accounts; otherwise, the woman was to be punished for making false accusations. Even in our supposedly more enlightened society, eyewitness testimonies still carry great weight in criminal trials - this despite ample evidence that they are often mistaken, resulting in many wrongful imprisonments.

The willingness of juries, and people in general, to believe eyewitness testimony stems from a faulty view of the nature of memory. Human memory is not like a tape recorder or a video camera, creating a record of events and then playing them back exactly as they were first observed. Rather, human memory is basically reconstructive: in most cases, we remember only the basic outlines of an event, and if we're called upon to retell what happened, the mind fills in the gaps with whatever details are at hand. This means that details that are fed to a person may subconsciously be incorporated into their memories and presented by that person as an accurate account of history.

One of the classic examples of this is an experiment done by the memory researcher Elizabeth Loftus. In it, Loftus interviewed the relatives of her research subjects to get three true stories of childhood events that had happened to each of them. To those three stories, she added a fourth one, which she confirmed with relatives had not actually happened: a story about the subject being lost in a mall at the age of five, crying and being comforted by an elderly woman, and finally being reunited with their parents. The subjects were each presented with these stories and asked to write down as much additional detail as they could remember about each of them. About 25% of Loftus' subjects "remembered" the fictitious account and described it as a true story that had happened to them in childhood (source). Similar studies along this line have found that, in follow-up interviews conducted later, more and more subjects remembered the false stories over time, with some even embellishing them with details of their own that weren't part of the original presentation.

Another study by Loftus found that subjects' memories of events can be altered by questions that presuppose a particular set of facts. In this experiment, 150 students saw a short film of an accident involving a white sports car and then answered questions about it. One set of students was asked, "How fast was the white sports car going when it passed the barn?" (There was no barn in the film.) The other set was simply asked, "How fast was the white sports car going?" One week later, both sets of students were brought in for a follow-up interview, and both were asked, "Did you see a barn in the film?" Students who had previously been asked about the non-existent barn were far more likely (17% vs. 2%) to incorrectly believe that it had been present the first time.

Even memories of highly emotionally charged events - so-called "flashbulb" memories - are just as likely to suffer this distortion. Just like any other memory, subjects tend to forget true details or add embellishments over time. But what's worrying is that, despite this error creep, people tend to put more confidence in their flashbulb memories and are more likely to believe they're accurate, even when the record shows otherwise.

And finally, the most sensational example of how memory can fail us: In 1975, the Australian psychologist Donald Thomson was arrested and charged with rape, and was informed by police that the victim had positively identified him as her attacker. This was a great surprise to Thomson, because he had a seemingly invulnerable alibi: he was on live TV at the time, being interviewed in the presence of a studio audience, cameramen, and an assistant police commissioner. As it turned out, the woman who was raped had been watching that very program just before the attack. She had mixed up Thomson's face on the TV screen with the face of her attacker. Ironically, Thomson had been on TV to discuss the unreliability of eyewitness testimony. (source; see also)

The human tendency to confabulate details and misattribute sources means that memory, especially in the long term, cannot be counted on as a reliable source of information. This doesn't mean that eyewitness accounts should be excluded from trials and other decision-making altogether, but they should be considered with greater attention to their fallibility. When we question witnesses about the details of an event, we must avoid leading questions that could implant details into their minds. When victims of crime are asked to pick their assailants out of a lineup, those lineups should be double-blind. And testimonies should be given greater weight when two or more witnesses independently agree on the same details or when they are supported by other evidence.

Other posts in this series:

• How to Think Critically

One of the more tiresome parts of being an atheist is having to deal with preachers who drag out the old apologetic cliches and convince themselves that they're being clever. Just so is this piece from one Rev. Eric Strachan:

[I] like to ask every atheist, "What percentage of the total knowledge that one could possibly acquire do you think you have?"

Interestingly, most answer around five per cent or thereabout. "Think again," I say. "It's more likely to be around .05 per cent!"

I then like to ask every atheist, "Do you think in the 99.95 per cent of knowledge that you don't have, there could exist the God who is the Father of Jesus Christ?"

Like Pascal's Wager, this argument turns up often in Christian apologetics, so I thought I'd write a detailed answer to it.

In the strict logical sense, yes, it's true that our knowledge encompasses only a small fraction of all the facts there are to know about the universe, and it's true that the existence of a god might be one of those unknown facts. It's also true, by that very same reasoning, that there might be leprechauns, dragons, unicorns, goblins, centaurs, fairies and Santa Claus. But that doesn't mean we have positive reason to believe in the existence of any of those beings. There's a vast set of facts that we don't possess, but since that set might contain absolutely anything, it's pointless to base our lives on speculation about its contents. That's why, as a general rule, we should believe only those propositions for which we have supporting evidence. We should and must make our decisions on the basis of what we do know, rather than what we don't.

But there's a larger fallacy in this argument, which is shown in the above quote with beautiful clarity. This fallacy is that the people making it are never just asking us to allow for the theoretical possibility of a god unknown to humanity somewhere in the far reaches of the universe. They are always asking us to believe in a very specific notion of God - a god whose personality, wants and desires they claim to know, and whom they believe has intervened actively in human history. In short, they themselves believe that God's existence lies not within the sphere of our ignorance, but the sphere of our knowledge.

The question is, how did they come by those beliefs? How can theists possibly hold such a specific, detailed conception of God, unless some fact somewhere within the 1% or less of things we do know gives them a justification for it? And if that's the case, they should be able to show us that fact so we can examine it ourselves. If they can't do this, or if the facts they propose don't stand up to scrutiny, then we are within our rights to dismiss their belief as unfounded and arbitrary. We are atheists precisely because all the god claims that we have so far surveyed have not stood up to this examination. Of course, we reserve the option to change our minds in the future if we find one that does - but given the repeated failures of these claims in the past, we rightly consider that unlikely.

Evidence is the golden thread that links belief to truth. It's the only reliable way to choose one belief in particular out of the vast and limitless ocean of possible beliefs, and to do so with confidence that the belief we choose will accurately represent the way the world truly is. If that evidence is not there, or if it's insufficient to bear the weight placed upon it, then that golden thread is severed and the belief is ungrounded, arbitrary. And considering how many possible beliefs there are, and the infinitesimal percentage of them that accurately represent the world, it's all but certain that an arbitrarily chosen belief is false. Asking a person to believe on such an arbitrary basis as faith is merely an invitation to be wrong. We atheists believe that one's worldview should be more solidly grounded than that.

Evangelical pastor Ray Stedman knows the root cause of everything that's wrong with the world:

It is not nationalism, it is not racism... it is the human heart. It is the pride of man that fancies he can get along without God.

But not to worry, because he advises us how we can conquer this obstacle. To achieve that, we must

...take captive every thought to the obedience of Christ. This is extremely important.

...It is absolutely necessary to do this if you want to have permanent victory. Allow these unChristian thoughts to remain unconquered, and you will soon have to take the fortress all over again. They will creep out of their hiding places and take over and you will find that that which God has delivered you from has taken control once again.

Granted, the job of "taking every thought captive" can be difficult, even for a believing Christian. Stedman observes that:

...the intellectual life is often the last part of a Christian to be yielded to the right of Jesus Christ to rule. Somehow we love to retain some area of our intellect, of our thought-life, reserved from the control of Jesus Christ. For instance, we reserve the right to judge Scripture, as to what we will or will not agree with, what we will or will not accept. I find many Christians struggling in this area.

One of our women told us, a few years ago, of a struggle in this respect in her life. She said she would read through the New Testament and sometimes write in the margin opposite a verse, "I don't agree!" Well, she was honest enough to put it down in writing. There are many of us who do not agree but we do not write it down, or even admit it to ourselves. It was honest of her to do that, but it represents a struggle with the Lordship of Christ; his right to rule over every area of life, his right to control the thought-life, every thought taken captive to obey him.

...Dr. Francis Schaeffer has put it very accurately beautifully in these words:

I am false or confused if I sing about Christ's Lordship and contrive to retain areas of my own life that are autonomous. This is true if it is my sexual life that is autonomous, but it is at least equally true if it is my intellectual life that is autonomous, or even my intellectual life in a highly selective area. Any autonomy is wrong.

Similar to C.S. Lewis saying that obedience is an "intrinsically good" habit to get into, or the Pope saying that a Catholic's only role is to obey the Vatican with sheeplike docility, both Stedman and Schaeffer agree that "any autonomy is wrong" and that we must never question, disagree with, or doubt the teachings of the Bible, lest we lose faith and be overcome by atheism. We atheists often say that religion "hardens hearts and enslaves minds", but it's interesting to see theists who openly agree with us and admit that this is exactly what they are trying to achieve.

What I find most revealing about all this is the sentiment that if you allow un-Christian thoughts to "remain unconquered", they will soon gain strength and overcome you; that the only way to maintain your faith is to crush all doubts and skepticism and force "every thought" into the Christian mold. It's bizarre that so many preachers say this is necessary. In what other areas of life do people do this? Do scientists tell each other that they must take captive every thought to the reigning theory, that even a seed of doubt may grow out of control? Do doctors constantly struggle to persuade themselves that they can heal sick people? Do chemists grapple with belief in the periodic table?

A New Yorker book review, Prisoner of Narnia, makes a similar point about C.S. Lewis' writing:

A startling thing in Lewis's letters to other believers is how much energy and practical advice is dispensed about how to keep your belief going: they are constantly writing to each other about the state of their beliefs, as chronic sinus sufferers might write to each other about the state of their noses. Keep your belief going, no matter what it takes — the thought not occurring that a belief that needs this much work to believe in isn't really a belief but a very strong desire to believe.

It seems that many believers wrestle with doubt; and since they haven't been able to get rid of it, they've elevated it into a virtue, saying that by its nature faith is hard to hold onto. In fact, this sentiment is so common that they don't realize how strange it is, or what it implies: that their reason is not entirely dormant, that it rejects the absurdities of faith, creating mental tension and doubt when it comes into contact with the will to believe. I've noted a similar phenomenon in those theists who feel flickers of conscience that cause them to agonize over their faith's cruel teachings of punishment and damnation. Neither the moral nor the rational sense, it seems, are easily quieted, and that is a heartening thought.

I'm aware this is anecdotal, but what strikes me is that I've never seen a comparable phenomenon among atheists. What atheist books or websites speak of atheism as something that's a constant struggle to keep up, or warn that if we read the Bible or consider arguments for the existence of God, religious thoughts may "creep out" and overpower us? I grant that many theists who claim to be ex-atheists assert that this can happen, but evidence for the phenomenon among actual atheists, in the same way Stedman discusses seeing among Christians, is conspicuously lacking.

And this leads to a simple, stunning realization: our apologist opponents are afraid of us. They boast of how their church is founded on the solid bedrock of the word of God, how their faith is strong and impregnable to contrary argument. But look past the surface, and in many cases, you'll find them constantly advising each other how best to stifle doubts, warning each other that our arguments must not be considered, our case not given heed. You'll find sermons sternly warning about the dangers of autonomy, of independent thought, and of using one's own best judgment. Why would they write so extensively about the necessity of taking your own mind captive - unless they fear what it would uncover if it was free?

In a previous post, "The Soft Landing", I wrote about the future and about one potential scenario that I find disturbing: that militant, fundamentalist churches will grow at the expense of moderate and liberal ones, leaving behind a world split between atheism and angry, intolerant religion. In this post, I'll again look to the future, this time to outline another possibility that I find worrisome in a different way.

In this scenario, both moderate and fundamentalist religion will decline together. But instead of secular humanism and rationalism growing in their place, a different belief system will fill the gap: not any kind of formal or organized religion, but a vague, amorphous, anything-goes kind of credulity. We already see devotees of such a belief system in the modern New Age and pagan movements, in the alternative-medicine and anti-vaccination camps, in the fans of TV psychics, alien abductees, ghost-believers, channelers, and preachers of the "law of attraction". The members of all these groups may not have any specific beliefs in common, but what unites them is the conviction that personal intuition is a reliable guide to truth, as well as a willingness to form their own beliefs by picking and choosing whatever sounds good to them.

A world such as this, instead of violence, would be more likely to suffer stagnation. Scientific discoveries would not be opposed by a rigid ideology, but diluted and drowned out by a society that cheerfully embraces every superstitious fad that sweeps by. For skeptics and rationalists, facing down such an amorphous enemy would be like cutting the heads off a hydra: for every one defeated, two more sprout in its place. And as more of society's resources are diverted from genuinely valuable and productive endeavors to serve the cause of credulity, the pace of progress slows, knowledge fades, and people value science and critical thinking less and less. Ultimately, we could squander the legacy of the Enlightenment and end up in a new dark age like the one we so recently struggled up out of.

What can we do to avert this outcome? The most important principle, I feel, is that we need to keep in mind that our mission should be broader than just attacking whichever supernatural beliefs are causing the most harm. Even if we were successful at that, human beings can dream up an unlimited number of new beliefs to replace whichever ones we vanquish. To win the battle against superstition, we need to work towards a broader goal: a renewed allegiance to reason and the principles of critical thinking in society. We need not just to point out the bad ideas, but to give people the tools to tell the difference between good and bad ideas for themselves.

What this means for us is that, to promote a brighter future of reason, and not just more diversity of superstition, atheists should be guardians of good education. We should see it as our role to ensure that public schools are universal, secular, well-supplied, and staffed by qualified teachers with a curriculum based in science and reason. As well, we must support the effort to make higher education accessible and affordable to everyone. Doing anything else - abandoning the poor to underfunded and inadequate schools, trusting that the market will solve the problem, calling for the privatization of education - is to invite every kind of superstition to take root and grow in the fertile soil of uneducated minds. Surveys consistently show that more highly educated adults are more likely to be skeptics and atheists; the converse is true as well. In the long run, investing in an educated public is an effort that will pay genuine dividends to all of us.

The testimonial is the favorite tool of pseudoscientists everywhere. Search the internet far and wide, and you'll have trouble finding a cancer-curing scam machine, thermodynamically impossible engine-conversion kit, or obscure psychic website that doesn't feature glowing testimonials from true believers. Eshu of Bridging Schisms gives many more examples, in his post "Testimonials and Research", like this gem from a satisfied client singing the praises of a psychic claimant:

"I came to Philena when I was in a very dark place. Through her patience, guidance and gentleness, I genuinely left feeling hopeful. She held me together emotionally and spiritually throughout this time. She lit the candle in my mind and let my spirit guide me to light. She has a wonderful personality and in my heart I know our paths were meant to cross."

And when the testimonial is given by a celebrity, people are especially susceptible. Often, the name of a famous person will attract consumers in droves to whatever product is being peddled, even if the celebrity endorser has no relevant knowledge that would allow them to evaluate the product with any more expertise than an ordinary person.

The influence of celebrity testimonials, and our infatuation with celebrities generally, probably have their roots in humanity's evolutionary heritage. The earliest human societies, like those of our ape-like ancestors, were small hunter-gatherer bands where individuals could rise or fall in status depending on their ability to sway the group. Although the rewards of being the group leader sowed the seeds of ambition in all of us, the tribe had to have stability for the sake of all its members' survival, which is why humans also have an inbuilt instinct to respect the authority of the alpha male or alpha female.

In modern society, where our social networks are vastly farther-ranging, celebrities have stepped into the role of alphas. We look up to them because, in a sense, we're programmed to do so. This is a predisposition that can be resisted through reason, but not if we're not aware of it.

The key thing to keep in mind about all testimonials is that, at best, they are anecdotal evidence. When it comes to alternative medicine, for instance, most diseases and injuries heal on their own. But if you just happen to be taking some dubious remedy when you begin feeling better, most people will credit their recovery to the treatment. Even a treatment that actually helps some people may be ineffective in others for any of a wide variety of reasons. And people who've already been persuaded of the efficacy of a treatment are much more likely to report positive results, and disregard any negative outcome that doesn't fit with their expectations.

For all these reasons, isolated anecdotes are of no value in judging the usefulness of any dubious claim. At most, they may be an indicator of which avenues might reward further exploration. At worst, they are outright deceptive, leading naive people to expect outcomes that are extremely unlikely. To truly judge the worth of a claim, we need statistical evidence that gives a genuine measure of likelihood that it will work. Thus, it's good news that the FTC is mulling requiring advertisers to report the average person's benefit from their product, rather than relying on "results not typical" testimonials. Marketers may howl, but in the long run it will help people make informed decisions and move the market as a whole in a more rational direction.

Other posts in this series:

• How to Think Critically

A few months ago, a theist contacted me by e-mail to claim that her church, the Mormons, had fulfilled many of the criteria set forth in my essay "The Theist's Guide to Converting Atheists". There was one criterion she thought was unfair of me to list - evidence of miraculous occurrences brought about through prayer:

This one is rough, mainly because faith must precede the miracle.

Similarly, another theist who contacted me by e-mail claimed that it didn't matter whether anyone could answer any of my arguments now, because God will answer them after I die if only I believe in him:

He will answer all your hard questions when you see Him face to face. It will all make sense then.

I've heard this argument from members of many sects - Mormons, Muslims, even Scientologists. All of them make the same claim, that God does not do miracles in front of unbelievers, that they are reserved exclusively as a reward for those who already believe. A similar claim comes from psychics who say that they can't demonstrate their abilities in the presence of skeptics like James Randi, because the skeptics give off "negative energy" that causes their powers to fail.

I marvel at the degree of doublethink that must be pulled off in order to sustain such an argument. For the religious apologists who make this claim, what they're essentially saying is that God chooses to withhold evidence until just after it's too late for it to make any difference. It's the opposite of how any scheme of rational persuasion should work: withhold evidence from those who are yet to be convinced; give evidence only to those who are already convinced. Such a plan could only be enacted by an irrational, capricious being who actually desired that people did not believe. What other motivation could there be for God refusing to reach out to the very people he's allegedly trying to persuade?

Given the vast number of incompatible religions and conflicting miracle anecdotes, it would be utterly unreasonable for a deity to expect people to somehow pluck the one true religion out of the multitude of imposters. Any god that truly wanted people to believe would be obligated to present clear and convincing evidence to distinguish itself from all the false faiths. How else could people possibly be expected to figure it out?

It's no surprise that this claim is repeated among superstitious and pseudoscientific belief systems of all kinds. This is exactly what we would expect advocates of a false belief system to say - because, for obvious reasons, that's the only thing a false belief system could say when challenged to present its supporting facts. "Believe first and then you get the evidence" is a convenient defense, one that relieves apologists of the troubling necessity of having to support their beliefs in any way at all. It also gives them a rhetorical boost by portraying doubt and skepticism as sinful actions which God chooses to punish by withholding evidence, an implicit attempt to claim the moral high ground and punt the burden of proof back to the questioner. And of course, once the prospective member already believes, no evidence needs to be presented.

The contrast between atheism and the faith-comes-first belief systems could not be clearer. Unlike religious worldviews, atheism makes no demand for belief before evidence. Unlike religious worldviews, atheism makes no claim to possess secret evidence that will be revealed only to those who approach with the proper attitude of humility and submission. In the light of reason, there is no secret evidence and no faith required in advance: we can freely present all the facts and invite people to make the most rational decision based on that.

Today's post on critical thinking concerns the five principles collectively known as Mill's methods, first presented together in 1843 by the Enlightenment philosopher John Stuart Mill in his book A System of Logic. Each of them is intended to illuminate the flow of causality in a different way, giving us mental tools to link causes and effects. In this post, I'll highlight past entries in my "Popular Delusions" series, and show how failure to properly use Mill's methods has duped the practitioners of pseudoscience.

1. The method of agreement. If two or more cases of the event you're seeking to explain have only one causal factor in common, that factor is probably the cause of the event.

Example: In my post on hauntings, I noted a way in which ghost-hunters conspicuously fail to apply the method of agreement: the vast majority of ghost sightings have nothing in common except that the people involved are in the twilight state on the edge of sleep. These conditions are most suitable for the human neurological state of sleep paralysis, which typically entails hallucination, inability to move, and a strong sense of a looming presence. This is a causal factor in common among these cases which ghost believers generally overlook. Since ghost sightings have little else in common, the method of agreement would suggest that sleep paralysis is the most probable cause of this phenomenon.

2. The method of difference. If there is one case where an event occurs and one case where it doesn't occur, and all the causal factors except one are the same in both cases, that one factor is probably the cause of why the event happened in one instance and did not happen in another.

Example: Astrology is an excellent example of misapplication of the method of difference. Astrologers claim that the celestial bodies and constellations that are ascendant at the time of a person's birth determine their subsequent traits of personality and character. This is the sort of claim that could be proven by the method of difference, but most astrologers are steadfastly uninterested in even doing the tests. Those few who have tried, using the method of difference to predict the personality characteristics of strangers based on their birth times, have been dismal failures.

3. The joint method of agreement and difference. If there are some cases where an event occurs and some cases where it does not occur, and all the cases where it does occur have only one causal factor in common, while all the cases where it does not occur lack that causal factor, that factor is probably the cause of the event.

Example: Faith healers are notorious for their ignorance of this method. If sick people who were prayed over frequently experienced otherwise inexplicable remissions, while people lacking such intervention never did, this would be strong evidence in favor of intercessory prayer. But all these conditions, in reality, are absent: sick people who receive prayer experience spontaneous recovery at rates no greater than chance, while spontaneous remission also occurs among people receiving no special theological intervention.

4. The method of residues. When seeking to explain the causes of a set of events, deduct all the causal factors which are known to cause some subset of those events; the remaining causal factors are probably the cause of the remaining members of the set.

Example: The method of residues is routinely ignored by proponents of homeopathy, who believe that a purported remedy can be diluted out of existence and still retain its curative power. A proper application of the method of residues would begin with the application of a chosen homeopathic remedy at full strength, then successively subtract the components of that remedy to observe how the effect diminishes. Homeopaths, however, believe the opposite: that as causes are progressively subtracted, the effects will grow greater in magnitude. This violates not just the laws of physics but the very notion of causality itself.

5. The method of concomitant variation. When two events or circumstances are observed to vary in the same proportions, such that an increase in one always accompanies an increase in the other, one is probably the cause of the other.

Example: This method is abused and misused not once, but twice, by the fanatical anti-vaccine campaigners. When they claim that the preservative chemical thimerosal causes autism in some subset of vaccinated children, they fail to take note of the fact that autism rates have been rising in recent decades even after thimerosal was removed from most vaccines. And in their steadfast denial of vaccines' efficacy in preventing deadly disease, they steadfastly ignore the declining rates of these infectious diseases, dwindling to near zero in many cases, which accompanied the widespread use of vaccination. And as vaccination declines among the superstitious, these diseases reappear and spread in turn - an unfortunately near-perfect example of the correlation that the method of concomitant variation reminds us not to overlook.

I first came across today's little-known Bible verse while reading The Pilgrim's Progress, and it was so amazing to me that I had to set the book aside and look it up on the spot. Search on the internet, and you'll find volumes of Christian apologetics seeking to justify the author's belief in God by claiming that they just know he exists because they can feel his presence in their heart:

The imagination knows God and the heart knows God, but the conscience silences the whole person because of a mysterious presence—total depravity. (source)

I feel God in my heart and I know is is always there.I read my Bible everyday and I pray amd meditate everyday, I have a heart of gold, I give to the uttermost(even when I dont have it to give)I pay my tithes and I have a lot of faith. (source)

If you are a person of faith who has always known in your heart that Darwin was wrong, the revelations on this website will help you to know with certainty that you were right all along, and that Darwin was wrong all along. (source)

I feel God in my heart, and I love the Lord so much. And when I feel him in my heart and when he's touching me, I just -- it just rolls over. (source)

The heart feels God, not the reason. This is what constitutes faith: God experienced by the heart, not by the reason. (source)

All these professions of faith, especially the last one by Blaise Pascal, express the belief that God's existence is not a matter of empirical knowledge, but is felt intuitively through a different and more profound inward knowing. This faith is often summed up by the statement "I feel God in my heart". And that's why it's so shocking that the Bible says this:

"He that trusteth in his own heart is a fool: but whoso walketh wisely, he shall be delivered."

—Proverbs 28:26

Since the book of Proverbs is just a collection of pithy sayings, it doesn't offer any context by which we could decide the meaning of this quote. It could mean, if you're feeling charitable, that we should not walk by faith and blind belief in our own infallibility, but should rely on facts and evidence to back up our decisions. This interpretation is remarkably similar to the secular humanist view.

However, it could also mean, and I suspect it was intended to mean, that religious faith is only acceptable insofar as it agrees with the Bible. The text is assumed to be infallible, and our religious beliefs are judged by how closely they agree with it. (This is how it was used in the Pilgrim's Progress, where this text is cited to justify condemning a character to eternal torture because he, though he claimed to be a Christian, did not believe that human beings are completely evil and depraved.)

In either case, however, it offers a ready counterargument to theists who claim to "just know" that God exists, or any other religious claim supported solely by personal intuition. The Bible itself states that the human heart is unreliable and that such claims are not to be believed. This verse is unlikely to set any believer on the road to atheism by itself, but it may help lead them to the realization that there are other, better ways of knowing by which we can learn about the world.

Other posts in this series:

• Little-Known Bible Verses