On 13 November 2010 I spoke to the Humanist Association of Manitoba on the subject of skepticism.
I’ve attached the audio of the talk here, along with a slightly compressed version of what I meant to say (no guarantees that it’s what I actually said). During Q&A I found myself trying to explain that being culturally relative wasn’t really cultural relativism. It had been a long day, and it may have been an epic logic fail. Judge for yourself!
I’m a skeptic. But what does that mean? It means a couple of things. First off, it means that I’m a grouch.
As humanists well know, atheism isn’t enough—not for me, anyway. The Raelians are atheists, for crying out loud. And so we have skepticism. To my mind, what I don’t believe is more important than what I do. Not because I’m a negative person, but because it seems to me that what I don’t believe is more indicative of the way that I go about figuring things out. And, if you attended SkeptiCamp last month, you know that I’m just mad for figuring things out.
It’s common to think of skepticism simply as doubt—and as far as one-word definitions go, that’s fine—but it’s not quite as simple as that. Are those who “doubt evolution” skeptics? Are those who doubt that the astronauts of Apollo 11 landed on the moon skeptics? Are those who doubt the germ theory of disease skeptics? I don’t think so.
Skepticism is not a position: it’s a method. It’s a method of critically examining and analysing claims, to sort those that are probably true from those that are probably not.
What should I look for?
So when we’re examining a claim, what do we look for?
- Plausibility: How well does this idea fit with what we currently know about how the universe functions?
- Falsifiability: Is the claim well and rigorously defined? Is there a way to prove it false, at least in principle?
- Evidence: Has the claim been previously investigated? If so, what were the results of the investigation?
- Sound Reasoning: Does the claim rest upon logical fallacies or cognitive biases?
We’ll start off with examples of some of the more common logical fallacies.
Appeal to Nature: This is when one claims that since a thing is natural, it is therefore desirable or good (or, conversely, when one claims that since a thing is unnatural, it is undesirable or bad). This is a subset of Hume’s classic is-ought problem.
Example: “Genetic engineering is unnatural, so you should eat only organic food.”
Affirming the Consequent: This is a converse error which assumes that the premises of a condition are true if the conclusion is true. It generally takes this form:
P → Q
Example: “If it is raining, the sidewalk is wet. Since the sidewalk is wet, it must be raining.”
Fallacy of the Perfect Solution: This occurs when one claims that a solution to a problem ought to be rejected because it is imperfect or will not solve all instances of the problem.
Example: “You shouldn’t use chemotherapy to treat your cancer, because the therapy is toxic and some people die even after being treated.”
I’m no fan of big pharma, and the multinational corporations who control the pharmaceutical industry certainly aren’t perfect. Unfortunately, I don’t have a better solution to the problem of funding research and supplying real medicine to people. In my opinion, regulation is certainly in order.
Straw Man: This involves mischaracterising an opponent’s position to make it easier to attack. This is very popular.
Example: “If evolution were true, we’d see cats giving birth to dogs. Since we don’t, evolution is false!” The “crocoduck” presented by Ray Comfort and Kirk Cameron also falls into this category.
I actually want to talk to you real quick about a trope in media that really bothers me. It’s the Straw Vulcan. Anyone know what I’m talking about?
It’s a straw man attack against logic itself. It’s when Mr. Spock tries to apply logic to solve a problem, fails spectacularly, and human emotion saves the day, and you’re left screaming at your television, “That’s not logic! You fail logic forever!”
I’m just going to quote directly from the TV Tropes page, because they get it so right:
Fiction often mixes up logical with other concepts… For one thing, authors sometimes say “illogical” when what they appear to mean is “counter-intuitive.” Correct logic is very often counter-intuitive … which is to be expected, as logic is meant to prevent errors caused by relying on intuition. As such it has more in common with mathematics than with Common Sense.
The term Straw Vulcan originates (of course) with Star Trek. A particularly glaring instance of Gene Roddenberry’s epic logic fail occurs in “The Galileo Seven”. Spock and Kirk are stranded in a shuttlecraft with insufficient fuel to return them to the Enterprise. Spock is forced to commit an “emotional” act by igniting their remaining fuel supply and hope that the Enterprise notices their makeshift beacon. It’s either burn the fuel in which case you might live, or just carrying on, in which case you certainly don’t. Even so, the act of igniting the fuel is labeled “illogical”.
This is really run-of-the-mill. The misportrayal of “cold logic” in just about every entertainment medium is endemic. And it bugs me.
Begging the Question: This is also called circular reasoning, and it occurs when one attempts to demonstrate that a conclusion is true by means of premises that already assume the conclusion is true.
Example: “God exists, because he inspired those who wrote the Bible, and the Bible testifies to his greatness.”
Argumentum ad Hominem: This is Latin for “argument to the man”. It is when one attacks the person, rather than the argument he or she is making.
Example: “You shouldn’t listen to what Darwin had to say because he was a racist.”
An aside about the ad hominem. If I say John Edward is an asshat, or Charlie Sheen is a moron, or Ray Comfort is a raving loon, that’s not a logical fallacy. The ad hominem only becomes a logical fallacy if I say Charlie Sheen’s claims that 9/11 was in inside job are false because he’s an moron. Similarly, it would be a logical fallacy if I claimed that the banana does not prove God’s existence because Ray Comfort is a raving loon. That’s not to say that the two must be unrelated, of course. Instead, I say Ray Comfort is a raving loon because he believes that the banana proves God’s existence.
Tu Quoque: This subset of the ad hominem attack is Latin for “you too”. It involves appealing to one’s opponent’s hypocrisy in failing to act in accordance to his or her own position.
Example: “Climate change isn’t real, because Al Gore, its most vocal proponent, has a huge mansion and drives a big car.”
Argumentum ad Populum: Latin for “argument to the people”, to commit this fallacy is to argue that a proposition is true on the basis that many (or most) believe it to be true.
Example: “200,000 Canadians can’t be wrong! Q-Ray. Find out what they know!”
Argumentum ad Consequentiam: Also called the argument from final consequences, this is Latin for “argument to the consequences”. This is when one argues that a proposition is true or false based upon the whether accepting the proposition leads to desirable or undesirable consequences.
Example: “If God did not exist, life would have no ultimate meaning.”
These are just a few of the many logical pitfalls that plague human thinking.
It’s important to remember that even if an argument is perfectly valid in structure and bereft of any logical fallacies, there are still cases in which it should not be persuasive. If the premises of an argument are false, the conclusion is unsupported regardless of the ironclad logic of the syllogism. “Garbage in, garbage out”, as we software developers like to say.
Now I want to talk quickly about some of the more common cognitive biases.
Confirmation Bias: This is our propensity to favour information that confirms positions that we already hold and to ignore evidence contrary to our own opinion. This often results in one-sided hypothesis testing and “cargo cult science“.
To quote Randall Munroe, creator of xkcd, the best webcomic in the known universe (yes, I just called you out, fans of SMBC): “You don’t use science to show that you’re right, you use science to become right.”
Selective Recall: This is a subset of confirmation bias which describes our propensity to remember the hits and forget the misses. It is relied upon by psychics and snake-oil salesmen to convince you that stuff is real when it’s not.
Inattentional Blindness: The inability to perceive things that are in plain sight as a result of distraction or focus elsewhere.
Change Blindness: The failure to detect major changes in a scene due to visual disruption (saccade, obstruction, etc.).
So by now, I reckon you should be absolutely terrified by the very concept of eyewitness testimony. I know that I am.
Falsifiability: This is the logical possibility that a proposition could be shown to be false, at least in principle. It is a very important principle in science and philosophy. It’s important to note that “falsifiable” does not mean “false”.
For example, which of these statements is falsifiable?
- “All humans live forever.”
- “No human lives forever.”
Now let’s compare these two statements:
- “I have a teapot in my home.”
- “Between the Earth and Mars there is a china teapot revolving about the sun in an elliptical orbit.“
Does that set of statements differ in any meaningful way from this set of statements?
- “The gods abide at the summit of Mount Olympus.”
- “God dwells extradimensionally, outside of space and time, and cannot be observed save by His direct permission.”
I would propose that for a proposition to be useful, it has to be falsifiable.
Jesus is Magic
Can the “God Question” be properly addressed by skepticism?
You first have to pick a god. They tend to have different properties. The Mormon god, for example, lives on the planet Kolob (or on a planet revolving around the star Kolob—interpretations vary). Deepak Chopra’s god, on the other hand, seems to involve abusing quantum mechanics to make money. (Or perhaps that’s a straw man?)
Let’s check our work:
- Sound Reasoning
I don’t believe in any gods, because they tend to fail in all four of the categories I outlined above. They’re unfalsifiable (or the tend to retreat into unfalsifiability—gone are the times when a simple trip to the summit of Mount Olympus would have done the trick); they’re implausible (at the very least, we’ve never encountered anything remotely like them); there is no unambiguous evidence for their existence; and the rationale used to argue for their existence is laden with poor logic.
I think that the God Question can be addressed by skepticism, but I recognise that taking that position does not put me in the overwhelming majority. Addressing religion tends to make people very uncomfortable—religious people, that is. But at the same time, addressing homeopathy tends to make homeopaths and their devotees very uncomfortable. Addressing spiritualism tends to make psychics and their enthusiasts very uncomfortable.
The problem is that people tend to identify themselves with their beliefs, and if their beliefs are threatened they feel like you’re insensitively attacking them.
So that’s the first lesson: I highly recommend that you don’t get personally invested in your beliefs. It’s surprisingly difficult, but it’s manageable. Instead, I identify with the process by which I arrive at my beliefs. My goal is that when the evidence changes, my mind changes with it.
Here’s where I really think that religion can be addressed by skepticism.
The Burden of Proof
If you make an assertion, it is not the other guy’s job to prove you wrong.
In the absence of unambiguous evidence, there are two possible default positions for belief: either believe proposition until it’s proven false or withhold belief until propositions are proven true.
People will often try to wriggle out of this choice, trying to claims some imaginary middle ground which simply doesn’t exist. You either believe a proposition or you don’t believe it. Given the proposition, “There is a dead body in the trunk of my car,” which works better? Do you assume that’s true until proven otherwise? The law certainly doesn’t, and neither should sane individuals.
The real problem with believing all propositions until they are proven false is that it is logically inconsistent.
By way of example, take these two propositions:
- “Leprechauns place a pot of gold at the end of every rainbow.”
- “Leprechauns do not exist.”
Absent any evidence for or against either proposition, one would be forced to accept both, even though they are mutually contradictory.
For this reason, if you make an assertion, it is your responsibility to provide evidence.
It is common practice among the intellectually dishonest to attempt to shift the burden of proof. I’m sure that we’ve all been asked to “Prove that God doesn’t exist!” This is similar to C.S. Lewis’ classic “liar, lunatic, lord” trichotomy. Not only is it an example of a false dilemma, if you assert that it is your opponent’s job to prove that Jesus was either a liar or a lunatic, you are attempting to shift the burden of proof.
I hear religious people frequently talk about “appreciating the mystery of life, the mystery of all of creation”, and I just want to scream, “You’re doing it wrong!” Yes, life is full of mysteries, and that’s a fine thing. But to speak of these great mysteries with such fulsome appreciation and to just stop there… that’s madness! That’s like admiring a fresh mocha cheesecake with Oreo crumbs on top, and saying: “What a delicious-looking cheesecake. I would wager that it tastes simply divine! Don’t you agree? It would appear to be just scrumptious!” Take a bite, why don’t you? Investigate the mystery. Saying “it’s a mystery” isn’t really appreciating the mystery at all!
Julian Begini expressed this quite well, I think: “It is arguable that humanism has a better grip on life’s mysteries than religion. For example, I’m genuinely in the dark about how the universe started, whereas plenty of religious believers have that hole in their understanding plugged by their deity.”
I’m going to tell you three stories, and I swear to you that they are true.
I used to work at a local dinner theatre. Several years ago (probably four or five by now), I was sitting with a friend of mine in the audience after the show, carrying on a conversation, when suddenly I froze. We both turned and looked toward the stage, which was approximately ten metres away, to my left and to her right. We turned back to face each other, and made to resume our conversation, when suddenly she asked me, “Did you just see something?” “Yes,” I replied. “I thought that I saw a blonde woman walking along the stage out of the corner of my eye, but when I turned to look, she was gone!” “Was she wearing a red dress?” my companion asked me. I thought back. “Yes,” I replied, “she was. I thought it was the stage manager.” It was then that our stage manager walked up from the booth, on the opposite side of the room, and asked what was wrong. It couldn’t have been her, I thought. She was on the other side of the room, and she’s not wearing red.
When I was fifteen, I stayed a few months with a rich friend of mine in his parents’ home, which could only be described as a mansion. It was a very old, very beautiful thing of red brick. It even had turrets! We would spend many an afternoon playing on the sloped roofs, to his parents’ considerable alarm. It also had a separate stairway that paralleled the main set of steps, made for servants (of which he had none). One day, I recall mounting the servants’ stairway on my way up from the basement, which was cavernous and somewhat frightening, even for a fifteen-year-old boy, when I thought that I heard something. I stopped, and listened, and I thought that I heard a cool voice, which I’d characterise paradoxically as entirely without character, say my name. Appropriately, I bolted.
I have one final tale, probably the most convincing for those who have a taste for anecdotes of this sort. I now live with my lovely and very supportive wife, but five years ago I lived alone. I was preparing a photo album for Laura, as she was going away for six months to visit Brazil. It was very late, and I was watching Star Trek: Deep Space Nine while I cut and sorted photographs. The paper-cutter that I was using slipped, and nearly took off my finger, and as it did I heard the remote control tumble to the floor. I cursed, and went searching for it, and came up empty-handed. I sighed and lifted the couch, and found only little balls of dust, and a stray pencil or two. I slowly and methodically cleared the photo-paper trimmings from the couch, removed the cushions and gave all of its cavities a search thorough enough to make the Department of Homeland Security proud. Nothing. I sighed again and went back to the photographs.
I spent much of my free time, over the next few days, searching for the remote. After about a week I finally despaired of ever finding it, and bought a “universal” one (for those of you who’ve tried to program one of these, you know why I put that word in air-quotes). A few days later, I was staring wistfully at a photograph of Laura (now on the other side of the world), when the telephone rang. I went to fetch it, and as I did I placed the photograph face down on the middle shelf of a white, three-tiered little stand that I believe was originally intended as a bedside table. When I returned for the photograph, it was gone.
Thinking of my lost remote, my consternation growing by the minute, I gave the area a good search. Then, convinced that my mind was playing some sort of cruel trick, I picked up every item on each tier of the stand, one by one, and asked myself, “Is this the photograph?” before placing it on the floor and moving on to the next. Nothing. Then, as the stand was white and I’d placed the photograph face-down, I ran my hands over every surface. Finding nothing, I finally picked the thing up and shook it. But to no avail. I finally sat down and wept with frustration and disappointment. “I just want my stuff back,” I moaned. A sat there a while before finally cleaning myself up and going about my day.
The next morning, I was groggily walking about, on my way to brush my teeth, when I happened to glance into a mirror on my wall. I let out a little (and somewhat emasculating, I must admit) shriek, for reflected in it was the little, three-tiered stand, and on the middle level, face-down, was my photograph.
A few weeks later, I found the remote. Although I still seem to remember the clunk that it made as it fell to the floor, it was buried in the couch. I found it quite accidentally: I terrified some friends who were over to play video games, as when I pulled it out of the couch I once again shrieked and tossed it across the room, where it bounced off the fireplace, eventually landing in someone’s lap.
I remember these things, and I swear to you that those stories are true. I have not made them up. These things happened to me. I remember these events as clearly as I remember the day that I met my wife or the first time I kissed a girl. (Incidentally, I don’t remember the first time I kissed a guy very well. I guess when something happens that many times it all kind of blends together… And now my wife looks rather alarmed. Moving on!)
I’ve probably put many of you in a fairly uncomfortable position. So, what the hell, let’s make it even more uncomfortable.
When I tell you these stories, how many of you believe me? Come on, I promise not to be offended—I’m actually rather difficult to offend.
Are you calling me a liar?
Well, that’s a little awkward. This is personal. I’m sure that most of you don’t want to call me a liar.
But what am I asking you, when I ask “Do you believe me?” Am I saying, “Do you believe that I was plagued by spirits?” Am I saying, “Do you believe that these things happened to me?” Or am I simply saying, “Do you believe that I remember these things happening to me, and this is how I remember them?” It’s not a simple question.
So. How many of you believe that this is how I remember the events?
And how many believe that these things happened to me, as I have told them?
And finally, how many of you believe that I was the victim of a haunting of some sort?
These things happened to me. I remember them happening to me. But I know better than to trust those memories. Things may well have happened differently. So let’s get out the skeptical toolbox.
“Spirits” may seem to be the simplest explanation for my experiences, but as an explanation it leaves much to be desired. While it purports to explain, however, it begets many more questions than it answers: the idea of disembodied spirits present even more complications than the idea of those still bound by their fleshy trappings.
- How does the spirit communicate with the brain?
- What functions does it perform that the brain cannot account for alone? (If souls exist, they would seem to be at the very least almost completely redundant.)
- Why does the spirit seems to be impaired in so many ways by brain injury and the like?
- Lacking sensory organs, how does an immaterial spirit perceive the material world? (If it can perceive the material world, why is physical blindness a hindrance at all?) Even if ghosts did have invisible eyes, invisible eyes wouldn’t work. If we are to see, light needs to strike our retina. If it passes through the retina, or around it, as it would if the retina were invisible, we would not be able to observe it. (With that in mind, I think that a certain member of the Fantastic Four has some explaining to do.)
- How does an immaterial spirit interact with or affect the material world? (If it can affect the material world, why does an embodied spirit control its host via the brain? Why not control its appendages directly?)
- If spirits do exist, why have none of them, particularly the scientifically-minded ones, attempted to communicate in such a way that it could be empirically verified? Surely Carl Sagan, Albert Einstein, et al could take some time off from exploring Andromeda and Triangulum to help push our scientific understanding further!
There’s another problem that I caught, too. Although I repeated the first tale faithfully, I realise that there is a glaring error in this version of it. The blonde woman in the red dress whom I putatively saw was in the periphery of my vision. Peripheral vision is provided predominantly by rod cells, rather than cones, and rods are useless for distinguishing colour; this makes colour vision in the periphery nigh on impossible (as can be demonstrated experimentally with cue-cards of differing hues). All the same, my memory is quite clear: the “ghost” was wearing a red dress.
I’ve heard it said also that ghosts are not souls (that’s ridiculous), but are instead “recordings” or “memories” or “resonances” of events and people past. But in what medium are such things recorded? How do they play out? How can such afterimages affect the physical world (which they must, if they generate sound or light, or even if they trick our brains into thinking that they do)?
On the balance, it seems much more likely that either I misremember my experiences or was in some way deceived, either by intent or by the failings of my own brain; but, as always, there may be another explanation. The thing is, I have memories of things that I know didn’t happen. I also don’t have memories of things that I know did happen!
Have you ever been telling a story to a large audience, only to catch a glimpse of your spouse looking puzzled out of the corner of your eye? She’s heard the story before, and you’ve told it dozens of times, but this isn’t quite the story that she remembers. Stories change in the telling. Not intentionally—not always—but they do change. When you tell a story, you change it, little by little.
What’s the harm in believing? Go to www.whatstheharm.net. They’re anecdotes. But they’re good anecdotes.
We can all be duped, and skepticism isn’t a cure. I think of it more like a vaccine: it won’t work for everyone every time, but there’s hope that one day we can achieve herd immunity.
If you get duped, it’s not because you’re stupid. Dr. Steve Novella summed it up like this:
It is easy for anyone to be overwhelmed by an organized campaign of misinformation. I know very bright people who were blown away by Loose Change when they first saw it. I know otherwise intelligent people who just cannot handle the systematic lies and distortions of the creationists – they don’t have the background and the volumes of information it would take to tackle each false claim and logical fallacy.
The same is true of the alternative medicine and anti-vaccine movement – they have a highly developed package of propaganda, misinformation, and subtle distortions – wrapped in a feel-good and empowering philosophy, that can easily overwhelm even an intelligent person.
So what can you do? Be intellectually honest. Confront the evidence, and if you’re wrong, admit it and change your mind. We all have our sacred cows, I’m sure, and we can do no more than examine our beliefs as reasonably as we can, and stand ready to abandon them when it is pointed out to us that our positions are untenable.
This is what one of the Novella brothers suggested: try not to be emotionally attached to your beliefs; strive instead to identify with the skeptical process by which you arrive at them. Although it is far from easy, it is something toward which we ought to strive.
“All men are fools, and he who does not wish to see them must remain in his chamber and break his looking-glass.”—Marquis de Sade
Women get a pass on that one, apparently.
Remember to check your work:
- Sound Reasoning
Don’t forget Ray Hyman’s Categorical Imperitive: Don’t try to explain a phenomenon until you’ve determined that it actually exists. A good example of an explanation in search of a phenomenon is King Tut’s “Curse”.
Let no question remain unasked because it is deemed impolite. Obviously there is a time and a place for everything, but don’t forget that you have a right to question everything. Freedom of expression is terribly important, as this is how the best ideas rise to the top.
I’m often accused of being closed-minded. Skepticism is not about being closed-minded—it’s actually about being open-minded. It’s about being open to having your mind changed. It’s about evaluating evidence and using that evidence as the basis for your beliefs. Admitting that we’re all capable of making gross mistakes about the world is being fairly open-minded, I’d say.
I’m going to let Tim Minchin have more-or-less the last word.
I’ll finish up with some startling things that I don’t believe in:
- Free Will
- Cultural Relativism (Mostly.)
- The “Singularity” (But wouldn’t it be nice?)