7/27/2009

Null Hypothesis

I am currently in Victoria visiting family and friends. My father in law subscribes to Scientific America, which had this article in it. You can find the original here. I enjoyed it, and instead of quoting bits and pieces, thought I would just post the whole thing.

Cheers,


Scott


In a 1997 episode of The Simpsons entitled “The Springfield Files” — a parody of X-Files in which Homer has an alien encounter in the woods (after imbibing 10 bottles of Red Tick Beer) — Leonard Nimoy voices the intro as he once did for his post-Spock run on the television mystery series In Search of…: “The following tale of alien encounters is true. And by true, I mean false. It’s all lies. But they’re entertaining lies, and in the end isn’t that the real truth? The answer is no.”


No cubed. The postmodernist belief in the relativism of truth, coupled to the clicker culture of mass media where attention spans are measured in New York minutes, leaves us with a bewildering array of truth claims packaged in infotainment units. It must be true — I saw it on television, at the movies, on the Internet. The Twilight Zone, The Outer Limits, That’s Incredible, The Sixth Sense, Poltergeist, Loose Change, Zeitgeist the Movie. Mysteries, magic, myths and monsters. The occult and the supernatural. Conspiracies and cabals. The face on Mars and aliens on Earth. Bigfoot and Loch Ness. ESP and PSI. UFOs and ETIs. JFK, RFK and MLK — alphabet conspiracies. Altered states and hypnotic regression. Remote viewing and astroprojection. Ouija boards and Tarot cards. Astrology and palm reading. Acupuncture and chiropractic. Repressed memories and false memories. Talking to the dead and listening to your inner child. Such claims are an obfuscating amalgam of theory and conjecture, reality and fantasy, nonfiction and science fiction. Cue dramatic music. Darken the backdrop. Cast a shaft of light across the host’s face. The truth is out there. I want to believe.


What I want to believe based on emotions and what I should believe based on evidence does not always coincide. And after 99 monthly columns of exploring such topics (this is Opus 100), I conclude that I’m a skeptic not because I do not want to believe but because I want to know. I believe that the truth is out there. But how can we tell the difference between what we would like to be true and what is actually true? The answer is science.


Science begins with the null hypothesis, which assumes that the claim under investigation is not true until demonstrated otherwise. The statistical standards of evidence needed to reject the null hypothesis are substantial. Ideally, in a controlled experiment, we would like to be 95 to 99 percent confident that the results were not caused by chance before we offer our provisional assent that the effect may be real. Failure to reject the null hypothesis does not make the claim false, and, conversely, rejecting the null hypothesis is not a warranty on truth. Nevertheless, the scientific method is the best tool ever devised to discriminate between true and false patterns, to distinguish between reality and fantasy, and to detect baloney.


The null hypothesis means that the burden of proof is on the person asserting a positive claim, not on the skeptics to disprove it. I once appeared on Larry King Live to discuss UFOs (a perennial favorite of his), along with a table full of UFOlogists. King’s questions for other skeptics and me typically miss this central tenet of science. It is not up to the skeptics to disprove UFOs. Although we cannot run a controlled experiment that would yield a statistical probability of rejecting (or not) the null hypothesis that aliens are not visiting Earth, proof would be simple: show us an alien spacecraft or an extraterrestrial body. Until then, keep searching and get back to us when you have something. Unfortunately for UFOlogists, scientists cannot accept as definitive proof of alien visitation such evidence as blurry photographs, grainy videos and anecdotes about spooky lights in the sky. Photographs and videos can be easily doctored, and lights in the sky have many prosaic explanations (aerial flares, lighted balloons, experimental aircraft, even Venus). Nor do government documents with redacted paragraphs count as evidence for ET contact, because we know that governments keep secrets for national security reasons. Terrestrial secrets do not equate to extraterrestrial cover-ups.


So many claims of this nature are based on negative evidence. That is, if science cannot explain X, then your explanation for X is necessarily true. Not so. In science, lots of mysteries are left unexplained until further evidence arises, and problems are often left unsolved until another day. I recall a mystery in cosmology in the early 1990s whereby it appeared that there were stars older than the universe itself — the daughter was older than the mother! Thinking that I might have a hot story to write about that would reveal something deeply wrong with current cosmological models, I first queried California Institute of Technology cosmologist Kip S. Thorne, who assured me that the discrepancy was merely a problem in the current estimates of the age of the universe and that it would resolve itself in time with more data and better dating techniques. It did, as so many problems in science eventually do. In the meantime, it is okay to say, “I don’t know,” “I’m not sure” and “Let’s wait and see.”


To be fair, not all claims are subject to laboratory experiments and statistical tests. Many historical and inferential sciences require nuanced analyses of data and a convergence of evidence from multiple lines of inquiry that point to an unmistakable conclusion. Just as detectives employ the convergence of evidence technique to deduce who most likely committed a crime, scientists employ the method to determine the likeliest explanation for a particular phenomenon. Cosmologists reconstruct the history of the universe by integrating data from cosmology, astronomy, astrophysics, spectroscopy, general relativity and quantum mechanics. Geologists reconstruct the history of Earth through a convergence of evidence from geology, geophysics and geochemistry. Archaeologists piece together the history of a civilization from pollen grains, kitchen middens, potshards, tools, works of art, written sources and other site-specific artifacts. Climate scientists prove anthropogenic global warming from the environmental sciences, planetary geology, geophysics, glaciology, meteorology, chemistry, biology, ecology, among other disciplines. Evolutionary biologists uncover the history of life on Earth from geology, paleontology, botany, zoology, biogeography, comparative anatomy and physiology, genetics, and so on.


Once an inferential or historical science is well established through the accumulation of positive evidence, however, it is just as sound as a laboratory or experimental science. For creationists to disprove evolution, for example, they need to unravel all these independent lines of evidence as well as construct a rival theory that can explain them better than the theory of evolution. They have not, instead employing only negative evidence in the form of “if evolutionary biologists cannot present a natural explanation of X, then a supernatural explanation of X must be true.”


The principle of positive evidence applies to all claims. Skeptics are from Missouri, the Show-Me state. Show me a Sasquatch body. Show me the archaeological artifacts from Atlantis. Show me a Ouija board that spells words with securely blindfolded participants. Show me a Nostradamus quatrain that predicted World War II or 9/11 before (not after) the fact (postdictions don’t count in science). Show me the evidence that alternative medicines work better than placebos. Show me an ET or take me to the Mothership. Show me the Intelligent Designer. Show me God. Show me, and I’ll believe.


Most people (scientists included) treat the God question separate from all these other claims. They are right to do so as long as the particular claim in question cannot — even in principle — be examined by science. But what might that include? Most religious claims are testable, such as prayer positively influencing healing. In this case, controlled experiments to date show no difference between prayed-for and not-prayed-for patients. And beyond such controlled research, why does God only seem to heal illnesses that often go away on their own? What would compel me to believe would be something unequivocal, such as if an amputee grew a new limb. Amphibians can do it. Surely an omnipotent deity could do it. Many Iraqi War vets eagerly await divine action.


There is one mystery I will concede that science may not be able to answer, and that is the question of what existed before our universe began. One answer is the multiverse. According to the theory, multiple universes each had their own genesis, and some of these universes gave birth (perhaps through collapsing black holes) to baby universes, one of which was ours. There is no positive evidence for this conjecture, but neither is there positive evidence for the traditional answer to the question — God. And in both cases, we are left with the reductio ad absurdum question of what came before the multiverse or God. If God is defined as that which does not need to be created, then why can’t the universe (or multiverse) be defined as that which does not need to be created?


In both cases, we have only negative evidence along the lines of “I can’t think of any other explanation,” which is no evidence at all. If there is one thing that the history of science has taught us, it is that it is arrogant to think we now know enough to know that we cannot know. So for the time being, it comes down to cognitive or emotional preference: an answer with only negative evidence or no answer at all. God, multiverse or Unknown. Which one you choose depends on your tolerance for ambiguity and how much you want to believe. For me, I remain in sublime awe of the great Unknown.

7/07/2009

The Reason For God - Chapter Four Review

Chapter Four of Keller's book is entitled, "The Church Is Responsible For So Much Injustice."
This is taking much more time and work than I expected. For this chapter I am going to bullet point Keller's rebuttals to the criticism and then my thoughts on the rebuttals.
  • People are affected by their emotional backgrounds with how they react to Christianity intellectually.
Interesting that Keller would start off with this, seeing how he so often rails against relativism.
I guess when one is critical, you must have met some naughty Christians. It felt like he was saying you could not be against Christianity without having some sort of personal grudge. I found this offensive, mainly because I want the message that I grew up with and loved to be true.
  • Many people with harmful pasts, abusive families and character flaws become Christians. Christianity is for people who realize they are sick and need the grace of g0d. Therefore it's to be expected that Christians would be a mixed bag of good and bad.
I hear this argument a lot when Christianity fails to live up to its own claims. The problem with this is, either your all powerful g0d changes all lives or he doesn't. I think it's very interesting that you get 'born again' experiences in all forms of faith. The appeal to 'we're all sinners struggling to get through' just makes me sigh and think that it is not really different from any other human created belief system.
  • All societies have killed and abused their citizenry. You can't just blame religious thought for this, even the commies did it, and they were atheists!
I guess I would say, again, this just leads one to say Christianity is another human created institution. If you're just like everyone else, and yet claim a supernatural source, where does that leave you? Keller using those evil commies as an atheistic society is interesting. Stalin was taught by the church, and used what he learned there to manipulate his people. He calls his list of societies that hurt people, and were not Christian, "rational and secular". That made me laugh. Secular maybe, rational I don't think so. I can't think of any society in history I would call "rational". I think it's very difficult to make a society rational. The whole "counting bodies" argument always tires me.
  • People who are super fanatical and hateful are not fanatical enough. If you were really fanatical about your faith, a 'real' Christian, then you would treat others with love. This is because you would be so humbled by being "accepted by g0d by sheer grace."
This seems to me to be the no true Scotsman fallacy.
  • Christ's own teachings have a built in critique against the abuses the church has done throughout history. Christianity teaches against the hypocrisy it has committed. You can't criticize Christianity without using it's own morals.
I think there is some validity in arguing that Christianity has not lived up to itself. I would probably take it a lot further than Keller, and say the argument could be made that Christianity sold out around the time of Paul. I am curious what Keller would make of Jesus being another apocalyptic Jewish teacher. That would change the view of Jesus' teachings.
  • Look at all the good that Christianity has done. From abolitionists to Bonhoeffer to Martin Luther King Jr. These are examples of 'true' Christianity.
This would work for me if you could not provide examples of the same thing in other faiths. As well, I could be mistaken, but I believe many of the first abolitionists were humanists. Also, King got much of his anti violence message from Gandhi. I don't say this to discount the good that Christians have done, but only suggest that maybe its origin are not supernatural. Christianity is just so very, well, human. The history of its church just makes that more clear.
I also find it very curious that all his examples happen after the enlightenment.

I feel Keller might have answered the criticism in a superficial way in this chapter, but missed the greater point.
Cheers,
Scott

Baloney Detection Kit

A worth wile watch for everyone.


Original video can be found here.
Hoping to do the next chapter review tonight.
Oh, Mr Deity has two more episodes up. lol.