Archive for September, 2014


Degrees of Doubt

A Lantern in the Dark #3


J Lantern

Doubt is one of the principal tools in the Skeptic’s toolbox, but we’re not cynics. We don’t automatically doubt every claim we confront. There are degrees of doubt. If you claim that you went to the movies yesterday, I have no reason to doubt you. Why would anyone lie about such an innocuous occurrence? Furthermore, the truth of your statement doesn’t really affect me in any tangible way. Why should I care if you didn’t go to the movies?

However, the credibility of the source is as important as the claim itself when assessing whether or not doubt is warranted. Maybe you’re a pathological liar. In that case, I have no reason to believe anything you say.

Some claims are extraordinary. Carl Sagan’s dragon is an excellent parable about extraordinary claims. For those that haven’t read The Demon-Haunted World, and I highly recommend that you do, I’ll briefly describe Sagan’s allegory.[1]

The story goes like this: someone (whom I will refer to, for simplicity, as him, though it could just as easily be a her) claims to have a dragon living in his garage. This is a pretty grand claim, indeed! Being skeptical, I say, “Great! Let’s go see it!” He replies, “You can’t. He’s invisible.” I propose scattering flour on the floor in an attempt to see the dragon’s footprints. He assures me that it doesn’t leave footprints because it flies all the time, never touching the ground. I suggest going into the garage and just walking around until we stumble into the dragon, but, I’m thwarted again. It is, I am told, insubstantial and can’t be felt.

On it goes. Every test I propose is defeated by some property that renders the dragon undetectable. I have no reason to believe it exists, since it seems to be indistinguishable from an imaginary dragon. Providing no good evidence, my fictitious friend has failed to meet his burden of proof.

Burden of proof is a contentious issue, especially in religious circles where there is a paucity of good evidence. In general, the person making the claim is responsible for proving the claim true. Oftentimes, people will try to shift the burden of proof to their opponent.

For example, I’ve debated with religious people whom I’ve asked to provide evidence that a god exists. They try to counter by turning the argument around, asking me to provide evidence that we live in a god-free universe.[2] Ignoring the fact that I never claim to know (an important distinction) that we do live in a god-free universe, this is a sophist’s tactic. It tries to leverage the difficulty (some say impossibility) of proving that something doesn’t exist (can you prove that unicorns don’t exist anywhere in the universe?)[3] That the universe exists is objectively true. Whether or not a god abides in, or outside of, the universe is the point in contention. In the absence of sufficient evidence, for or against (as in the case of a god), Occam’s Razor is a useful tool most of us instinctively use to help decide what to believe.[4]

William of Ockham was a 14th century friar who’s eponymous maxim for efficient reasoning was interpreted by Bertrand Russell as follows: “if one can explain a phenomenon without assuming this or that hypothetical entity, there is no ground for assuming it.”[5] In other words, in the absence of sufficient evidence to determine which of two theories (equivalent in all other respects) is true, opt for the one that makes the fewest, or least improbable, assumptions (i.e., is the simplest).

Later, my fictitious dragon keeper’s garage burns to the ground. He comes to me proclaiming that he finally has evidence for the existence of the dragon, since it has used its fire-breath to burn the garage down! Unfortunately for him, I saw a pile of oily rags heaped in the corner of his garage, which are known to spontaneously ignite. My friend has failed again, because, even though I didn’t actually see the rags catch flame, it is the explanation for which the underlying assumptions are most credible.

There are some rather extraordinary claims that do warrant belief. Relativity and quantum mechanics are counterintuitive explanations of motion in space and time. The flow of time isn’t constant? Space can stretch and curve? Particles can be in multiple locations at one time? These theories have been thoroughly tested over the last century and have withstood every challenge. Quantum mechanics is one of our most successful theories in physics. The same can be said for Evolution. Not just well tested, there are many concepts in biology that would be very difficult to explain without Evolution (unless, of course, you believe in an omnipotent deity; then all things are explained—except, of course, the deity). The theories underlying our understanding of climate change are also firmly supported by evidence, to the point that virtually all climate scientists believe climate change is happening, and that it’s caused by human activity.

To be a good Skeptic, you have to carefully balance doubt so as not to become a cynic. Skeptics want to ensure that, as much as possible, the things we believe are true. We want to have an open mind, but not so open that our brains fall out. The more incredible the claim, the more good evidence we will require. What constitutes “good” evidence? That’s a topic for another day.


  1. The Demon-Haunted World – Science as a Candle in the Dark © 1996 by Carl Sagan, pg. 160
  2. William Lane Craig, a Christian apologist and debater, commonly uses a form of this tactic by asking his opponents to provide an argument or evidence to show that “atheism is true.” (For an example, see the transcript of this debate with Christopher Hitchens.) This is only impressive to people who don’t really understand what atheism means.

    Atheism is simply that one finds there is insufficient evidence to justify belief in a deity. Substitute this into Craig’s (paraphrased) request: provide an argument or evidence to show that one finds there is insufficient evidence to justify belief in a deity is true. Now it is readily apparent that Craig’s question is nonsensical. Whether or not one finds the available evidence sufficient to warrant belief is a personal determination. Everyone will have a different threshold. Craig is well aware of this, and uses this blatant casuistry as a cheap ploy to win audience support. In the minds of the spectators, he is asking his opponent to prove there is no god, which they will fail at since a proof is impossible.

  3. See this Wikipedia article and this James Randi video.
  4. See this article for a discussion of the burden of proof.
  5. See http://en.wikipedia.org/wiki/William_of_Ockham

A Lantern in the Dark #2

by J. Lantern

The London Skeptics blog has sat idle and neglected for many months now; I hope to rectify that. To that end, this is my inaugural post, once removed. Though the London Skeptics group generally tackles issues important to the skeptic community (religion, pseudoscience, alternative medicine and other quackery, etc.), and I certainly plan to post many entries discussing these topics, I won’t necessarily hold to these constraints. Basically, I plan to talk about whatever is stuck in my craw on a weekly to biweekly basis.

Comments are welcome, but polemics and ad hominem are not. There’s a place for that: reddit. Although I don’t plan to set draconian standards for comments, I would like to keep it clean and free of insults. Criticism is fine, but I don’t suffer pedants kindly. Trolls will be ruthlessly slain, figuratively speaking. Finally, make sure your comments don’t look anything like spam, or they won’t survive review! You’ve been warned.

Finally, a word about the title: “A Lantern in the Dark”. I chose it specifically for its double meaning. Some may find my posts a dim candle in figuratively dark places. Others may think I am stumbling about blindly in a gloomy room, barking my shins on the furniture. Most will probably be somewhere in between. Either way, the title works.

So, let’s begin. I should point out that what follows is just my opinion. Feel free to disagree. You’ll just be wrong 😉

What is a skeptic (or sceptic)? Here’s what my Collins dictionary has to say:

sceptic n 1. a person who habitually doubts generally accepted beliefs.
n 2. a person who doubts the truth of a religion.

This captures an important feature of the kind of skepticism I’m talking about—doubt—but, it doesn’t tell the whole story. This is a little too close to cynic. Skeptics (i.e., capital-S skeptics) practice scientific skepticism. Belief is withheld until adequate evidence has been shown, prompting a change in belief—we may not accept your position at face value, but we’ll try to keep an open mind, and examine the evidence brought to the table. This is what separates Skeptics from conspiracy theorists. Conspiracy theorists and purveyors of pseudoscience frequently describe themselves as “skeptics”, but show them evidence that refutes their positions and they will find some way to justify discounting that evidence. Their minds tend to be closed to new evidence once they’ve bought into the narrative of the conspiracy. At their worst, they will stoop to name-calling (“you’re a shill for Big-X“, “you’ve been brainwashed”, or “you’re one of the sheeple”).

Skeptics, hopefully, counter pseudoscience and conspiracy theories with facts. Do we always succeed in staying on the argumentative high ground? No. Of course not. We’re human too. But, for myself, I strive to keep discussions civil and fact-based, and try to listen carefully to what my challenger is saying. I am skeptical, first and foremost, of my own knowledge. I am keenly aware of my own ignorance, becoming more so as I age. If, as Socrates said, knowing you know nothing is the beginning of wisdom, then I have become very wise indeed. I wish I was 20 again, when I knew everything 😉

So, to create my definition of a Skeptic, I would add to the definition above that while a Skeptic’s default position may be to doubt, they remain open minded to new evidence, regardless of what conclusion that evidence may lead to.

What constitutes good evidence? Hopefully, something we can all agree on. This is the largest rift that seems to exist between my opponents and me. My preference is for objective, scientific observations. Not everyone is so picky. One fraudulent and poorly done study by Andrew Wakefield launched the anti-vaccine movement, with the terrible consequences for those families whose children have contracted easily preventable illnesses.

How does one know good research from bad? That’s a difficult question to answer. Here are a few red flags:

  1. Press conferences before publication. Remember cold fusion? Pons and Fleischmann couldn’t wait to tell the whole world about their brilliantly flawed discovery.
  2. In medical trials, small sample sizes. Trials with a few dozen subjects just aren’t large enough to minimize the statistical chance of a fluke. Look for a low p value.
  3. Grandiose claims. Again, remember cold fusion? It was going to completely revolutionize how power was generated. Sometimes a breakthrough will produce a sea change in society, but, claims ahead of the fact should be met with considerable skepticism. Tim Berners Lee didn’t know what would unfold when he created the basic technology underlying the world wide web.
  4. The research violates established scientific laws. Breakthroughs and paradigm shifts do happen in science, but they tend to enhance established theories, rather than supplanting them. Einstein’s theory of special relativity reduces to Newtonian physics (the older model) under the right conditions. On the other hand, there is no scientific basis for homeopathy.
  5. The claim uses established scientific terminology in novel ways. Think Deepak Chopra and his gratuitous bastardization of the word “quantum”.
  6. It’s being promoted by a celebrity. Bill Maher promotes naturopathy and “skepticism” of vaccines. Gwyneth Paltrow and Jennifer Aniston believe “cupping” promotes health. I could go on…
  7. It was in that ridiculous movie ‘What the Bleep Do We Know’. The moon is still there, even when no one’s looking at it.

This is not an exhaustive list by any standards, and some people may disagree with some of these points. But it may be a helpful start for some people. I don’t claim to be perfectly skeptical in all aspects of my life, but I try to improve every day. No one wakes up one day, decides to be a skeptic, and promptly throws out all of their unsubstantiated beliefs and prejudices. Like most things in life, becoming a Skeptic is a journey, best taken with like-minded people who can help each other over the rough spots. I hope to meet you on my own trek to becoming a better Skeptic.