Frequent Listener Feedback
Skeptoid answers some listener emails that present common flaws in scientific thinking.
by Brian Dunning
January 24, 2012
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Today we're going to go through a few pieces of Skeptoid feedback that represent a lot of common misconceptions about how science is done, and how knowledge is advanced. Often, when I have a conversation with someone, they'll express faulty logic such as ghosts or aliens must be real because there was an anomaly, I know something must be true because it happened to me or to a friend, or just having a fundamental misunderstanding of some science. Today we've got emails that cover each of these bases, and I'll give my responses to each.
Like a lot of people, Steve from Redmond, Washington has the whole "burden of proof" concept backwards. Generally speaking, in science, the burden of proof lies on the party making a conclusion that moves away from the null hypothesis. For example, in the question of alien visitation of Earth, the null hypothesis is that no strong evidence exists either for or against. If you assert that Earth has definitely not been visited, then you bear as much of a burden as does the person who asserts that Earth has been visited. Steve wrote in regarding the episode on the megalithic structures at Pumapunku, calling out my conclusion that there's no reason to introduce anyone other than the Tiwanaku for their construction projects:
...The stonework shows evidence of precision machining and repeatitive craftsmanship unlike any other site and this cannot be ignored the way you have. Further many of the carved stones are reportedly diorite and granite exceedingly hard materials.
Are you asserting that a culture barely out of the stoneage was capable of carving stone with a near diamondlike hardness with this level of precision with primitive tools? If so kindly explain how?
Debunking rumors requires you prove that such a thing is possible. You cannot simply handwave and say "maybe they found a way". You must scientifically show a methodology. If you cannot present a solution using their level of technology, you have debunked nothing.
Steve's made a number of errors. To begin with, there is no diorite or granite at Pumapunku, despite a lot of paranormalists promoting this statement to make the carving seem more impressive than it really was. Pumapunku is almost all clay and rubble, with facing stones of sandstone and a bit of andesite. It is very well carved, but it's hardly "unlike any other site". Pumapunku is not nearly as impressive as a number of other sites from the ancient world, such as the Greek Parthenon, the Palace of Darius at Persepolis, and the Udayagiri Caves in India. I did not ignore this in the episode at all, in fact I made these specific comparisons.
But his biggest error was in saying that my discussion failed because the burden of proof was on me. The null hypothesis of Pumapunku is that it is exactly what it appears to be, and what all the historical and archeological accounts show it to be: a city of the Tiwanaku culture dating from about the year 500. We do not need to be able to prove which of the many possible stonecutting techniques was used in order to observe that the stonecutting was indeed accomplished. It's right there. The null hypothesis need not be complete in every detail; it still remains the null hypothesis. We'd love to know which techniques they used, but they simply didn't leave enough evidence.
If there were any observations from Pumapunku that are irreconcilable with our knowledge of ancient peoples — for example, if the stones were indeed impossible to carve or too heavy to move — then that would change the null hypothesis. In that case, saying that Pumapunku was built by the Tiwanaku would be the extraordinary claim. But this isn't the case; there simply isn't anything there that is unexpected or surprising to archaeologists. Pumapunku is very beautifully done, but it's hardly the only case of human beings doing high quality or difficult work.
Jarek from Kettering, Ohio wrote in about my episode on Stalin's human-ape hybrids, which studied whether or not the Soviets ever actually tried to create such hybrid creatures like the popular urban legend claims. Like a lot of people, Jarek has made a value judgement based on faulty knowledge:
Because of the ear mouse, there has been a huge public backlash against any type of research mixing human and animal genes. Lots of states have passed laws banning human-animal hybrids. That might be a good topic to do an episode on. Scientists have lost public support on this issue and are now viewed as mad and unethical, and for once I agree with that assessment.
Jarek's is a fairly common misunderstanding of technology. The "ear mouse" he refers to was an experiment in growing replacement cartilage, performed in 1995. A strain of lab mouse was used that was immunocompromised, meaning that (among other traits) it would not reject foreign tissue. A biodegradable structure in the shape of an ear was placed under the mouse's skin, and was seeded with bovine cartilage cells. The idea was to see if the cartilage would grow, and it did; potentially showing that it may be possible to grow human transplant tissue the same way. There was no genetic connection between the mouse and the cells in the ear structure. The mouse was a perfectly normal mouse, and the cartilage was bovine. The reporting media didn't always get this right, and many people, such as Jarek, had the wrong idea that it was some kind of bizarre genetic hybrid creature.
It's quite common for people I speak with to reveal that their objection to some technology is based on a misunderstood concept. Objection to a technology, for any reason, is everyone's right; but I don't think many people would disagree that it's best to properly understand what it is you think you're objecting to. In this particular case, Jarek's casting a giant umbrella over a wide spectrum of biological research, some of which he might not object to if he understood it better.
Trying to breed a race of half-human creatures is pretty extreme, and few would probably support that; but what about the use of cell cultures to produce life-saving vaccines, or gene therapy to correct Parkinson's disease? These are more debatable ethics questions. It's often risky to use a single fat brush to paint an entire field of research as either completely good or completely bad.
Another common — in fact, almost universal — response to skeptical thinking is "My experience was X, thus X is correct and anything else is wrong." Maybe this is "ghosts are real" or "reflexology works", all based on uncontrolled personal experience. Here's an email from Naomi, a former nurse in Michigan, who wrote in response to the section in the detoxification episode where we discussed colon cleansing:
I suppose it may not matter to you, but I can state without reservation and in all good conscience that you are wrong in your assessment of bowel cleansing theory and (one) currently marketed product. I had a long career as a nurse; I've handled, well, let's see how to phrase this nicely: "Lots of bedpans with loads of...stuff" in them" and also have used one of these maligned products with great benefit. Frankly, I don't care what any organization or individual views as "truth." I prefer personal experience to someone else's opinion.
Working as a nurse, or anything else, does not guarantee scientific thinking. Personal experiences are uncontrolled, meaning they are subject to a vast, unknown number of variables. External factors, personal biases, preconceived notions, and misinterpretation of results all combine to make anecdotal personal experiences nearly useless as far as being reliable sources of information.
Of course Naomi's probably right to put more stock in her own experiences than in someone else's opinion, but there was no opinion component to the data discussed in my episode. When we want to know something, we can guess or form an opinion or even rely on anecdotes, but it's not a very good way. A better way is to design a test, where we eliminate variables by such processes as randomization, blinding, and statistics. What this process has shown us about colon cleansing is that it has no known health benefits, nor has anyone suggested a plausible reason that it might. It does, however, present considerable risk of infection and injury, and is at best an unnecessary expense.
A question I'd ask Naomi is how would she suggest confirming her experience to the satisfaction of the doctors? Does she think that designing a clinical trial would be a good idea? If she agrees, then it's easy to direct her to the literature that shows her experience has failed to be replicated once controls were applied to remove the variables that were present during her experience. If she doesn't agree that testing is an appropriate way to improve knowledge — and many alt-med proponents think this way — I'd remind her that virtually everything she depends on for transportation, communication, and even eating, is the result of research and testing.
Finally, here's an email that demonstrates the tendency of some true believers to cling to a desired conclusion, and to ignore or misrepresent any information they come across that contradicts it. James from the Ozarks wrote in about my episode on the Starchild skull, the skull of a child who died in Mexico some 900 years ago, and who probably had untreated hydrocephalus, which caused the skull to be grossly enlarged. Some, like James, insist that the skull is a human-alien hybrid; the only evidence for which is a mitochondrial DNA test they had done — which tests the maternal DNA — and found it to be human; thus, "compatible" with their hypothesis that it had a human mother and an alien father:
This article is full of inconsistent information bordering on out right lies. Current Dna Analysis of the Star child skull shows that the mother was human but the fathers DNA came back as no known species, the Nuclear DNA was placed against those of known species in a data base of millions of known species and there was no match. None! You should actually do research and get current findings before you make yourselves the authority on something you know nothing about.
The literature does not contain any record of a test such as James describes, nor any need for one. There was one other DNA test done, which looked for certain sequences unique to humans. It was indeed human, and in fact had both X and Y chromosomes. We know from the mtDNA test that its mother was an American Indian, and the fact that it also had a Y chromosome (which is passed from the father), that it had a father with a Y chromosome and who was able to breed with a human woman. This is not consistent with James' understanding. James has either not read the Starchild literature (the same thing he accuses me of), or he was not able to understand it and so morphed it in his own mind to conform to his desired conclusion that the skull is alien, or is deliberately disdainful of it. All three are possible, and all three show James to be ideologically motivated to insist upon the alien explanation.
With some people, you just have to move on.
By Brian Dunning
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Cite this article:
Dunning, B. "Frequent Listener Feedback." Skeptoid Podcast. Skeptoid Media,
24 Jan 2012. Web.
9 Dec 2016. <http://skeptoid.com/episodes/4294>
References & Further Reading
Beck, E. "Sex and Genetics Before the Flood." The Newsletter of The North Texas Skeptics. The North Texas Skeptics, 1 Feb. 2008. Web. 21 Jan. 2012. <http://www.ntskeptics.org/2008/2008february/february2008.htm>
Chappel, M. "Colon Therapeutics 23-Oct-03." FDA.gov. US Food and Drug Administration, 23 Oct. 2003. Web. 25 Dec. 2009. <http://www.fda.gov/ICECI/EnforcementActions/WarningLetters/2003/ucm147792.htm>
Goldacre, B. "Be Fit: The Detox Myth." The Guardian. 8 Jan. 2005, Newspaper: 9.
Janusek, J. Identity and Power in the Ancient Andes: Tiwanaku Cities Through Time. New York: Routledge, 2004. 133-137.
Novella, S. "The Starchild Project." The New England Skeptical Society. The New England Skeptical Society, 1 Feb. 2006. Web. 14 Jan. 2010. <http://www.theness.com/index.php/the-starchild-project/>
Young-Sánchez, M. Tiwanaku: Ancestors of the Inca. Denver: Denver Art Museum, 2004. 32-34.
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