# Debunking Denialism

Defending science against the forces of irrationality.

## Butchering Scientific Studies

Sometimes, people who promote pseudoscience online try to reference the scientific literature. In one sense, this is progress. They are going from just making arbitrary assertions to trying to justify them. In another sense, it is a turn for the worse. That is because the papers they reference are either of incredibly low scientific quality or rarely support what is being claimed. However, the behavior gives the illusion of evidential support for some readers. A lot of the time, they damage their own position by spamming long lists of links to videos and blog articles, but some promoters of pseudoscience are more sophisticated.

Previously, I wrote a short introduction on how to counter cranks that reference the scientific literature. Consider this to be the intermediate to advanced version. It will attempt to provide scientific skeptics with additional tools to counter pseudoscience online. The focus will be on research articles, specifically clinical trials. However, the general arguments can often be extended to other forms of research articles. Some of the tools are evidential or methodological in nature and directly related to the meat of the article such as whether or not there was a control group or control for confounders, the appropriateness of the statistical analysis and whether the conclusion accurately reflected the results. Others are more sociological in nature, looking at the journal itself, the presence or absence of peer-review, impact factor, who the authors are etc. These do not necessary count against the research in the article directly and should not be used alone, but provide useful external arguments if combined with criticisms of the study itself. There is of course some overlap between and within these broad categories.

First, a word of warning. Knowledge can be used for good or evil, and this is no exception. It is very dangerous to find oneself in a situation when the studies that run counter to one’s position are subjected to merciless criticisms while the research that support it is being accepted with little or no critical thought. This is known as pseudoskepticism and something to avoid at all cost. It can even undermine the rationality of some of the giants in science seemingly without difficulty. Read more of this post

## How HIV/AIDS Denialists Abuse Bayes’ Theorem

Image by Matt Buck, under Attribution-ShareAlike 2.0 Generic.

Note: Snout (Reckless Endangerment) has made some good arguments in the comment to this post. The gist is that HIV/AIDS denialists overestimate the false positive rate by assuming that the initial test is all there is, when in fact, it is just the beginning of the diagnostic process. Snout also points out that it is probably wrong to say that most people who get tested have been involved in some high-risk behavior, as a lot of screening goes on among e. g. blood donors etc. I have made some changes (indicated by del or ins tags) in this post because I find myself convinced by the arguments Snout made.

There have already been several intuitive introductions to Bayes’ theorem posted online, so there is little point in writing another one. Instead, let us apply elementary medical statistics and Bayes’ theorem to HIV tests and explode some of the flawed myths that HIV/AIDS denialists spread in this area.

The article will be separated into three parts: (1) introductory medical statistics (e. g. specificity, sensitivity, Bayes’ theorem etc.), (2) applying Bayes’ theorem to HIV tests to find the posterior probability of HIV infection given a positive test result in certain scenarios and (3) debunking HIV/AIDS denialist myths about HIV tests by exposing their faulty assumptions about medical statistics. For those that already grasp the basics of medical statistics, jump to the second section.

(1) Introductory medical statistics

A medical test usually return a positive or a negative result (or sometimes inconclusive). Among the positive results, there are true positives and false positives. Among the negative results, there are true negatives and false negatives.

True positive: positive test result and have the disease.
False positive: positive test result and do not have the disease

True negative: negative test result and do not have the disease.
False negative: negative test result and have the disease.

For the purpose of this discussion, $+$ will indicate a positive test, $-$ will indicate a negative test, $HIV$ will indicate having HIV and $\neg HIV$ will indicate not having HIV.

$P(A)$ is the probability of an event A, say, the probability that a fair dice will land on three. Conditional probabilities, such as $P(A \mid B)$, represents the probability of event A, given that event B has occurred. If A and B are statistically independent events, then $P(A \mid B) = P(A)$, if $P(B) \neq 0$ (because the definition of $P(A \mid B)$ has $P(B)$ in the denominator).

Let us define some conditional probabilities that are relevant for HIV tests and Bayes theorem: Read more of this post

## The Widespread Abuse of Heritability

Together with evolution, heritability is perhaps one of the most misunderstood and abused concepts in biology.

Some white supremacists appeal to moderate to high estimates of heritability for phenotypic traits to justify genetic determinism, that genes explain between-group differences, the discrimination of ethnic groups or other malignant and pseudoscientific beliefs that are incompatible with science.

Some egalitarian dislikes scientific results regarding moderate to high heritability estimates because they believe that it indicate that the environment is unimportant in explaining the phenotype of individuals and latch onto single studies showing low heritability as if that meant that genes are less important.

As we shall see, both of these groups believe things that are flawed from a scientific standpoint. But before we discuss why and how this is, it might be beneficial to know something about what heritability actually is. Our definition of heritability will be unpacked and improved in several stages to facilitate understanding. Read more of this post

## Some Falsehoods about the Y chromosome and Male Brains

Note: Greg Laden has made a comment on this post saying that I misrepresented his position. I am open to the possibility and have therefore asked some follow-up questions, but at the time of writing this note (2012-07-26 22:23 GMT +1 DST), Laden has not clarified the situation for me. Keep this in mind while reading this post. Will update this again when he does.

Note: I just noticed (2012-07-28 22:08 GTM +1 DST) that Heina Dadabhoy did not mean what she actually said, but said it as a joke in response to a tweet by Zvan. There is an alternative explanation, namely as a post hoc rationalization when Heina discovered that she had been called on it, but it seems less likely. In essence, this means that we can probably consider both the claim made by Greg and Heina to be jokes or awkwardly expressed science. The only think left now is for Greg to finish writing up his follow-up and/or setting me straight by explaining more in detail in what way I misrepresented him.

Note: As a clarification (2012-07-28 23:06 GMT +1 DST) for Kelseigh Nieforth (‏@Nezchan), I reject this alternative explanation. It is possible, but relatively implausible. I did not intend to sound “mean-spirited & insulting”, quite the opposite. My intent was to rebuke what I felt was going to be the standard misogynist reply (i.e. claiming that Heina only said it was a joke when she noticed it had gotten a lot of attention and reflected badly upon her).

Note: Greg Laden has clarified his position over at his Scienceblogs blog. The general idea is that testosterone alters the male brain during different stages of development and “damaged” referred to the fact that androgens and other biosocial factors influence certain men to be more statistically likely to exhibit socially noxious and harmful behaviors that are incompatible with progressive, egalitarian and peaceful world. I have no general problems with this position (note added 2021-08-03 20:16 GTM +1 DST).

Note: This blog post has been linked by a men’s rights activist blog. All forms of discrimination is morally wrong, but most men’s rights activism I have come across seems to be equal parts pseudoscience and blanket anti-feminism. I therefore, in general, reject men’s rights activism. This post should not, and cannot, be interpreted as giving men’s rights activism any support, whatsoever (clarification added 2012-08-04 14:14 GMT +1 DST).

The background to this story is that Heina Dadabhoy and Greg Laden, at a panel discussion on gender differences at SkepchickCon/CONvergence, claimed that the Y chromosome was “broken” and that the male brain is a female brain damaged by testosterone. Amidst substantial criticism of these claims, the FtB blogger Stephanie Zvan decided to take upon herself to defend these flawed notions. As we shall see, her attempt is filled with incorrect characterizations and selective use of the scientific literature,

But first, let us make sure we have understood the claims being put forward in the video, so that we do not incorrectly characterize them as something they are not. A video of the panel discussion can be found here. I will post enough of the discussion for context, but readers are encouraged to check if I have gotten everything right. Laden was especially hard to take a transcript of, because he talks very fast and often changes mid-sentence, but hopefully I got the gist. It starts with a question from the audience at 35:41 about the gender differences in autism diagnosis and how males are supposedly more often autistic than females:

Heina Dadabhoy: That is an underdiagnosis issue, actually. They have been doing more and more research on women and autism. A lot of us women who fall on the spectrum only find out when we are adults, because a lot of the behaviors that manifest…the ways that girl tend to manifest it is slightly different and you know a girl who gets obsessed with something they are like “oh, well she is a girl and she has her little obsessions, how cute and when it is a boy it is like “oh, why isn’t he out beating up his peers?” so that is a big issue with autism.

Member in the audience: …inaudible… [probably something to do with differential disease susceptibility between genders e. g. red-green color blindness or hemophilia - E. K.]

Heina Dadabhoy: That is the Y chromosome. It’s broken [Dadabhoy smiles and laughs - E. K.]

Greg Laden: There is… there is … One thing that psychology does…There is some reasonable evidence that certain….There are gender differences.. [inaudible]. But there are gender differences. One of the most important gender differences.. in other words males versus females do not overlap that much at all… in certain areas and one of…one place they do not overlap at all, and you can’t change this… with culture… much..like you can change spatial orientation by giving everyone Tetris when they are born and will be the same. What we can’t change is that, for example, is the number of kids that cannot read until much later…the age at which you start to read and how you have dyslexia and so on that are boys is an order of magnitude higher in girls and you can do everything you want to fix that and you can only fix them a little bit. Most of those differences disappear and are not necessarily that significant, but is real. You know, the male brain is a female brain damaged by testosterone in various stages in it’s life. I think probably there are some very interesting adult difference…you cannot look at at a person and say that, but population differences between males and females that has to do with brain development because hormonal differences and…most of them are probably kind of trivial but there probably are some…yeah autism…I don’t think that is an example of one, but there probably are some things but if we where that different, it would be a hard time communicating…[inaudible].

So, right of the bat we can see that Zvan has incorrectly characterized both what Dadabhoy and Laden had stated. Dadabhoy stated that the Y chromosome was broken, not, as Zvan wants to have it that the Y chromosome is a broken X chromosome. Laden stated that male brain is a female brain damaged by testosterone in various stages in it’s life and did not use the term development. As we shall see, it is these false characterizations that Zvan’s bases her arguments on, but the bigger problem is that Zvan has no scientific foundation for her argument, leading the entire tortuous justification of the notion that men are genetically and neurologically “broken” to collapses onto itself.

The Y chromosome is not broken, but contains 86 unique and functioning genes

In her attempt to justify the absurd notion that men are genetically broken, Zvan appeals to the fact that the Y chromosome cannot recombine with the X chromosome to the same degree that the X chromosome can with another X chromosome. While this is true, this does not justify the original claim that the Y chromosome is a broken X chromosome, or the stronger claim that the Y chromosome is broken. In fact, the Y chromosome contains 86 fully functioning genes and this does not even count the genes that exists on both the X and Y chromosome. For the vast majority of individuals, the Y chromosome is fully functional and does not produce genetic defects or pathology. So nothing is actually “broken”.

X-linked recessive disorders signify a problem with the X chromosome, not the Y one

Zvan points out that males are more at risk for certain heritable disease because the related gene only occurs once, while in females it occurs twice (since they have two X chromosomes). This is also true, but the causative factor is the disabling mutation in the X chromosome that causes the disease, not something to do with the Y chromosome. So in other words, what is “broken” in these cases, is the X chromosome, not the Y.

Lack of large-scale recombination is sometimes a good thing

The loss of an ability for large-scale recombination is not something uniformly bad. In fact, if large-scale recombination between the Y chromosome and X chromosome was possible, it could result in males without the necessary sex-determining or sex-influencing regions in their Y chromosomes and females with harmful genes only found on the Y chromosomes, so the lack of large-scale recombination between X and Y is clearly adaptive. A loss does not need to be evolutionary or physiologically detrimental. Read more of this post

## Genetic Risk Factors and Parental Responsibility

The interaction of nature and circumstance is very close, and it is impossible to separate them with precision. Nurture acts before birth, during every stage of embryonic and pre-embryonic existence, causing the potential faculties at the time of birth to be in some degree the effect of nurture. We need not, however, be hypercritical about distinctions; we know that the bulk of the respective provinces of nature and nurture are totally different, although the frontier between them may be uncertain, and we are perfectly justified in attempting to appraise their relative importance.

- Sir Francis Galton, Inquiries into human faculty and its development (1883).

The nature versus nurture (or biology versus the environment) controversy has raged on for thousands of years. Modern science, however, has rejected this dichotomy as trivially false. It is not nature versus nurture, but nature through nurture. Both play essential roles in shaping organisms such as ourselves and they often interact with each other. However, as Galton remarked above, one could still discuss the relative merits of partial biological and environmental explanations. When people reduce the complex interaction of biology, psychology, biological and social environment to “mostly biology” or “mostly environment”, they are perpetually restraining humanity into the black-and-white cage that is nature versus nurture, despite paying lip service to modern science. Worse is that “mostly biology” is incorrectly interpreted as some form of genetic determinism, whereas “mostly environment” is erroneously conceived as the notion of the blank slate and the hail of vitriolic straw man arguments begin. The fact that some Internet commentators, journalists and other interested parties do not have sufficient scientific understanding, especially with regards to biology and psychology, makes it even more troubling. This, in turn, leads to a lot of misunderstandings about the science.

Clearly not the best setup for an intellectually productive discussion. Read more of this post

## The Intellectual Bankruptcy of Eugenics

For the purpose of this article, eugenics is defined as “the belief that certain individuals should be killed, be forced to undergo sterilization or other be exposed to other coercive measures to prevented them from reproducing in order to protect the population from harm and to ensure the genetic quality of future generations”. I will occasionally attribute other beliefs to eugenics, such as beliefs in “racial purity” or that evolutionary beneficial implies moral, so let’s consider this a working definition for now. Yes, I am aware that there are people who support other forms of eugenics based on voluntarism etc. but those groups are not the target here.

As we shall see, there are many problems with eugenics. It is based on a multitude of scientific falsehoods, has huge practical problems, it is arguably not cost-effective and wildly unethical. Some of these points are somewhat overlapping, but they emphasize specific problems.

1. Eugenics is based on artificial selection, but this is in practice mainly useful for selecting genes with additive effects. However, most genes have interacting effects, making eugenics less efficient, although not impossible.

2. Eugenics is based on a naive view of development. There is hardly never a direct 1:1 relationship between one gene and one phenotypic trait. In general, most traits are polygenic (influenced by many genes) and most genes are pleiotropic (affect many different traits). It is more accurate to think of the situation as a huge, complex network of genes and gene products influencing each other. The heritability of personality traits and certain complex hereditary diseases tend to be moderate (calculated from twin and adoption studies). Using Genome-wide association studies to analyze hundreds of thousands of single nucleotide polymorphisms (SNPs), scientists have found that candidate SNPs can only account for a fraction of his heritability (“missing heritability problem”). This may be accounted for by rare gene variants that are unique for different populations, variation in copy number or genetic interactions.

3. Eugenics is based on a naive view of the power of genes. Genes tend to be risk factors for certain conditions, where environment can act as the trigger. A classical example is the condition know as phenylketonuria (PKU). The genetic risk factor is a mutated version of a gene coding for the enzyme known as phenylalanine hydroxylase that catalyze the hydroxylation of the amino acid phenylalanine to tyrosine. When this is non-functional, phenylalanine accumulates and is converted to phenylketones. This in turn causes mental retardation, brain damage and seizures. An incredibly successful treatment is a diet free of phenylalanine and monitoring of the blood levels of this amino acid. In this case, environmental interventions are more beneficial, cheaper and less unethical than eugenics.

4. If you imagine the general problem outlined in point 3, but instead think of it being hundreds of different genetic and environmental risk factors, then you have an approximate view of most complex human diseases.

5. Even for so called single gene disorders, an individual with one copy of the defect allele and one copy of the healthy allele may have a selective advantage. The classic example is that a person heterozygous for the allele that in the homozygous condition causes sickle-cell anemia has a higher resistance to malaria. The allele, although detrimental in the homozygous condition, is retained in the population by balancing selection. Eliminating gene variants that cause disease in the homozygous condition may lead to less prevalence of individuals with heterozygous advantage. Read more of this post

## Belief and Knowledge

Helen Quinn is a particle physicists at the Stanford Linear Accelerator Center and a former president of the American Physical Society and also has been involved in science education and the public understanding of science. Quinn has written an extremely important article that was published a few years ago in the journal Physics Today called Belief and knowledge—a plea about language, dealing with how well-defined scientific concepts are sometimes misunderstood and even abused by the public, which is often incredibly frustrating.

Quinn starts with a personal anecdote: as her husband where describing the topic of his thesis to a layperson, which was using a coincidence set up for to see that two particles detected simultaneously where most likely coming from the same event.

I remember the puzzlement of a friend as my husband described his thesis research—a coincidence experiment. His listener stopped listening; she was thinking about why anyone would try to measure coincidences. I pointed out that the word “coincident” simply means “occurring at the same time.” The experiment used its precise timing to ensure that two particles detected at the same time had a very high probability of coming from the same source event. Thus the term coincidence was used in a sense opposite to the everyday meaning, where a coincidence is two uncorrelated events that come together. Words shift their meaning; each community develops its own usage. That change in meaning leads to miscommunication.

Quinn points out that this problem does not just arise with the term coincident, but with other terms, such as theory and energy and explains how this can lead to misunderstanding of science. Read more of this post

## Summary of Victor Stenger’s Case against the Fine-tuning Argument

Victor Stenger is a physicist, philosopher and prolific author, and has recently published the book The Fallacy of Fine-tuning: Why the Universe is Not Designed for Us. It contains perhaps the best currently existing response to the creationist argument from fine-tuning from the perspective of physics. Now, other philosophical and mathematical responses exists, but this is a comprehensive overview of the scientific case against the fine-tuning argument. I will summarize some of the more interesting parts of Stenger’s case below by paraphrasing certain parts of the last part of the final chapter in the book (pp. 293-294) as well as mentioning other problems mentioned in other parts of the book.

1. Many proponents of the fine-tuning argument quote Stephen Hawking out of context to try and show that Hawking thinks that the expansion rate of the universe is fine-tuned. In reality, Hawking just lists this problem as a problem for the big bang theory before cosmological inflation is taken into account. When it is, the fine-tuning problem of the expansion rate goes away.

2. Many proponents of the fine-tuning argument appeal to the singularity theorem proved by Hawking and Penrose in order to try and established that the universe began in a singularity. However, a singularity would be very massive and have infinitesimal volume. This is forbidden in quantum mechanics due to Heisenberg’s uncertainty principle, which states (in one of its versions) that the uncertainty in momentum times the uncertainty in position cannot be less than a specific non-zero number. Thus, the theorem proved by Hawking and Penrose is not applicable anymore.

3. Claims about fine-tuning are made against the backdrop of our particular form of life, yet other forms of life may be possible. Read more of this post

## The Top Five Most Annoying Statistical Fallacies

Mathematical statistics and probability is hard. It often involves what, at a first glance, involves complicated calculations and the sheer volume of data coming out of some studies can often be hard to interpret, even if you know all of the mathematics behind it. Although it is important to understand the math, it is equally important (or perhaps even more important) to understand what the results mean and don’t mean. It is easy to get dazzled by fancy mathematics or over-interpret results to mean something they really do not. Therefore, a basic understanding of statistical fallacies should be a part of every scientific skeptics toolbox or baloney detection kit.

Here is a list of the most common statistical fallacies, what they are and how to combat them.

1. Confusing correlation with causation

A correlation is when two variables vary together, whereas. For instance, ice cream sales may increase in the summer and decrease in the winter. The same may be true for drowning accidents. Does this mean we can draw the conclusion that drowning accidents causing ice cream sales? Does this mean that people have become so selfish and morally vile that they prefer to buy ice cream and watching people drown than trying to save them!? Fortunately, not really. Just because two variables vary together does not mean that one caused the other. It might be that the other caused the first, that they both cause each other or that a third factor causes both. In the case of ice cream sales and drowning accidents, a third factor that probably explain the correlation is season. In the summer, more people eat ice cream and go bathing, but fewer to these things in the winter. Confusing correlation with causation is widespread in many areas of pseudoscience, such as the anti-vaccination movement; one of their claims is that as the number of vaccines given have increased, so has the rates of cancer. This shows that the two factors correlate, not that vaccines caused cancer (in fact, the vaccine against HPV and Hepatitis B can prevent cancers) is a correlation, not a causation. A more likely factor is better healthcare as a third factor; better healthcare has meant more vaccines, but also increased lifespan, which is associated with an increase in the risk of cancer.

2. Post hoc

Post hoc and denotes the fallacy of thinking that A causes B just because B follows A in time. This fallacy, like the fallacy of confusing correlation with causation, is understandable from an evolutionary perspective. Those that where too skeptical of attributing an upset stomach to poisonous berries where less likely to reproduce. However, this kind of instinct-based reasoning can no longer be thought of as justified in our modern society Read more of this post

## Symphony of Science: Combining the Awe and Wonder of Science with Music

John Boswell is a musician and producer that has made some of the best music videos about science ever. According to his website, called The Symphony of Science, the “goal of the project is to bring scientific knowledge and philosophy to the public, in a novel way, through the medium of music. Science and music are two passions of mine that I aim to combine, in a way that is intended to bring a meaningful message to listeners, while simultaneously providing an enjoyable musical experience”. He does this by remixing and tuning spoken words by scientists and putting them together with photos and clips from lectures given by them. The videos and audio can be downloaded at the website, but the videos are also posted on Youtube.

At the time of this writing, there are 17 videos of pure awesomeness.

Watch them, rate them, add to favorites and spread the beautiful message of science. Boswell has hit upon an idea that may transform the way the general population views science. It is an enormously powerful approach.

## What is Scientific Methodology?

What exactly is science? Thinkers from Aristotle to Larry Laudan have pondered some version of this question and come up with different explanations or criteria. Most of us have seen the linear method containing steps like coming up with an idea, testing it and evaluating the results. This, however, is an oversimplification and the real process of science. This does not mean that rules of thumb like falsifiability is wrong or unhelpful, however, science is much more dynamic, combining interacting features such as exploration, testing, interaction with society and communicating results in the peer-review literature.

There are many factors influencing the start of scientific exploration. It could be a practical problem, like how to reduce smog from a major city or treat malaria, it could be due to the development of new technology, such as biotelemetry equipment that reduces effects of measurements in animal research, or simply unintentional accidents, like Alexander Flemming’s discovery of penicillin. It can also be due to being put into a research group, talking to academic advisers, reading an exciting new article in the peer-review literature and so on.

When designing an experiment in many areas of science, a null hypothesis is often tested. This is usually stated as no statistically significant different between two groups, two treatments or two physical variables. Results can often be confusion, hard to interpret or inconclusive. This spurs further research, trying to fix the problems or approach the issue from a different angle. Often an experiment needs to be useful, coherent and cost-effective.

Research is often published in the peer-review literature, presented at scientific conferences, discussed with colleagues and used to build upon the state of knowledge by improving explanations and models or replicating already existing research in order to critically evaluate it.

Some of this knowledge can be used to improve our life and society, from finding the link between smoking and lung cancer and treating infections to renewable sources of energy and designing smarter computers.

## Appeal to Scientific Consensus is not an Appeal to Popularity or Authority

A common claim among various kinds of pseudoscientists such as creationists or climate change denialists is that appealing to scientific consensus is either an appeal to the popularity of a position or an appeal to an authority and that therefore, appealing to scientific consensus is a logical fallacy.

However, appealing to scientific consensus is not the claim that “the scientific community is an authority or that it is a popular position, and therefore correct”, but rather, there is an additional premise in the appeal to scientific consensus that does not normally exist in the average appeal to authority. To elucidate the difference, let us see how this plays out.

P1. There is a scientific consensus on X (evolution, global warming, HIV causing AIDS or whatever).

Now, had we gone straight from this to the conclusion that X is true, it would have been an argument from authority or appeal to popularity. However, let us not forget our additional premise.

P2. If there is a scientific consensus on X, then it is probably the case that X is a reasonable scientific conclusion supported by most different lines of converging evidence.

In general, the scientific community as a whole is very conservative in making strong statements, because as we all know, making categorical statements may come back to haunt you. So we can be reasonably sure that, in the majority of cases, a consensus position is at the very least support by most currently known evidence. It is easy to see how the following conclusion follows.

C. It is probably the case that X is a reasonable scientific conclusion supported by most different lines of converging evidence (from P1 and P2 by modus ponens).

Too be sure, the scientific community is not infallible or always right. However, when the majority of the evidence available supports a position, it is reasonable to hold it as a tentative conclusion regardless.

## How to Critically Read and Evaluate a Scientific Paper

There are many pseudoscientific groups out there, from creationists and 9/11 truthers to opponents of vaccination and psychiatry that attempt to prop up their beliefs by referencing the scientific literature. However, they often do this in deceptive ways, either misrepresenting good science or taking it out of context or referencing to bad science, published in journals with very low credibility and often not even peer-review. If you are ever faced with someone who is clearly presenting pseudoscience referencing the scientific literature, there is one overarching rule to keep in mind: read the article. I cannot possibly stress this enough, read the article, or at least read a credible summary of it or an already written debunking of the argument using that reference from a reliable source. The goal of this post is to serve as a short introduction to how to read and critically evaluate a scientific paper.

How do you gain access to the paper in question? Easy. Buy it online, or go get a library card from a university library. They often give you the ability to access the papers remotely. Sometimes you can find the paper in full online, if it was published in an open access journals. Key questions we should ask ourselves are: does the article support the claim that the person referencing does? Is the article published in a peer-review journal? What is the impact factor of the journal? Is the method flawed? Is the conclusion in proportion to the results? Have there been independent replication? We will look at these questions, and more, below. But first, let us take a look at what a scientific paper looks like. I have been intentionally vague so far in what I mean by a scientific paper. There are actually two main categories of scientific papers (there are more): research article and review article. Let us look at review articles to begin with. Read more of this post

## Refuting “Radiometric Dating Methods Makes Untenable Assumptions!”

A very common claim of young earth creationists in trying to reject the evidence for an old earth is to loudly proclaim that radiometric dating methods “makes assumptions” and that these “assumptions” are somehow fatally flawed or not supported by evidence. These claims generally land in three different categories: (1) radiometric dating assumes that initial conditions (concentrations of mother and daughter nuclei) are known, (2) radiometric dating assumes that rocks are closed systems and (3) radiometric dating assumes that decay rates are constant. Most young earth creationists reject all of these points. As a scientific skeptics, we ask ourselves: is this really the case? Let us critically examine each of these claims and see if they hold up against the science. While doing so, we will have to learn about how radiometric dating actually works.

There are many different kinds of radiometric dating and not all conclusions we will reach can be extrapolated to all methods used. Also, different radiometric dating techniques independently converges with each other and with other dating techniques such as dendrochronology, layers in sediment, growth rings on corals, rhythmic layering of ice in glaciers, magnetostratigraphy, fission tracks and many other methods. This serves as strong evidence for the reliability of radiometric dating methods.

1. How does radiometric dating work?

A lot of atoms are stable. Some are not. There exists different versions, or isotopes of many elements. These isotopes differ in the number of neutrons they have in their nuclei. Those isotopes that are not stable decay into daughter nuclei. Those that did the decaying are called parent nuclei. If you have a rock that contains radioactive isotopes, these will decay over time. As time goes on, the ratio of the parent to daughter nuclei will change and decrease (as more parent nuclei decay into daughter nuclei, the former decreases and the latter increases). Measuring this ratio gives us an idea of how long ago the rock formed.

But wait a second! Doesn’t this assume that the rocks are closed systems? Surely, if some daughter nuclei left the rock or parent nuclei entered the rock, the dates would come out all wrong! While this is technically true, there are several mini-industries dedicated developing methods and techniques to make sure that there is no contamination and check to see if the rocks where disturbed between forming and being tested by scientists. How is this done? Let’s find out! Read more of this post