I work most days on building critical thinking skills and am also on Facebook and other online sites each day. These two items go together. After all, if looking to spot logical fallacies, it is best to search for them in their natural habitat.

I have yet to see a definition of critical thinking that I find satisfactory. I have been working on my own, but am still at it. More than anything else, though, it is sticking to the point. Most logical fallacies in some way deflect the key point or stray from it.

Another distinction is that critical thinking reaches conclusions that are logically supported by a series of sound premises. Just declaring something to be so without offering proof is inadequate.

One key to critical thinking is to detach one’s self from one’s beliefs, for they are not the same. This may be the hardest part of the exercise. Cognitive dissonance and the backfire effect are potent enemies of critical thinking. But they can be overcome with practice. 

I saw an anti-vax article that included a graph which showed that measles rates were going down before the vaccine was introduced. To think critically about this, I would need to investigate the claim for accuracy and analyze what it would mean if true. Just dismissing it as the ramblings of a pro-disease lunatic would not be thinking critically.

Multiple reputable sources confirmed the chart’s findings. But this does not mean that the eradication of measles from U.S. is not owing to vaccination. Measles is an endemic disease, so populations can build resistance to it, but it can also be deadly when introduced to a new population. This, when combined with measles’ highly contagious nature and the susceptibly of preschoolers to it, explains the nine spikes on this chart, occurring at approximately four-year intervals. There has been no such spike, or even a tiny bump, since the vaccine was introduced in 1964. In fact, there were 364 measles deaths in 1963, and none in 2004, a reduction of 100 percent.

As this experience demonstrates, I am never afraid to have my views and beliefs challenged. If they are correct, they will survive the challenge. If they are wrong, I will be enlightened. Not everyone can embrace this concept. I have been unfriended multiple times for respectfully pointing out inconsistencies in an argument or offering a different opinion. Some persons are that welded to their positions. I can only lead them to the dihydrogen monoxide, I cannot force them to consume the liquefied molecule.

Maintaining its status as the runaway frontrunner for most frequent logical fallacy is the ad hominem. This is where the retort is to belittle the speaker rather than attempting to counter the argument. This is most often in the form of a genetic fallacy. It is ubiquitous in the anti-vax and anti-GMO camps, where the shill line is frequently employed. It is so extreme that some anti-vaxxers accused billionaire Mark Zuckerberg of being paid by Big Pharma to post a photo of his daughter getting her shots.

Almost every time the shill accusation is made, it is untrue and childish. But more importantly, it is irrelevant to the argument. I often point there are 1,783 studies that suggest GMO safety, and that vaccines work by mimicking disease in order to prep the immune system for the real thing. These statements are true whether or not someone is clandestinely paying me to write it.

Another common logical fallacy is the strawman. This is making up or greatly misrepresenting the opposing position to make it ridiculous and easy to tear down. For example, Ken Ham claims skeptics are desperate to find evidence of life on another planet since it would bolster the case for evolution. He then gleefully points out that no such evidence has been uncovered, so this proves the other side is wrong. In truth, skeptics are the most vocal in questioning claims of ancient aliens, abductions, Roswell, and Nirubians. Part of the reason for this position is realizing that the enormity of space makes contact unlikely, and that any hypothetical alien civilization would had to have developed the same type of technology as us for signals to reach from one planet to another.

Another example of misrepresenting a position comes in the form of challenging persons to shake disassembled watch parts in a box and see if a working timepiece results. This is meant to speak against the idea of random chance, and by extension, evolution. I could issue a counter challenge of providing an empty box and asking God put a watch in it. But that would be the logical fallacy of appealing to hypocrisy. A better response is to point out that while mutations are random, the natural selection that drives evolution is the opposite of chance. It’s also rather silly to tie the changes of biological population over time into a broken up Rolex, but that’s a little beyond a critical thinking lesson. So we’ll move on, but stay with the religion vs. atheism theme. 

Christian apologist author Frank Turek says there must be a God because if men created their own values, morals would be subjective and everyone would have their own and chaos would result. However, this is the argument from consequences. Whether chaos would result has no bearing on whether man got his idea of right and wrong from a deity or through experience, reflection, observation, upbringing, and society. As an aside, I don’t think Turek takes his morality from the Bible; otherwise he would support ISIS members who sell their daughters into slavery and stone adulterers.

Now we’ll look at some fallacies are that are more difficult to spot. Ad hominem are easy to detect since the person isn’t addressing the argument. We can know an argument to be a strawman if the opposing person didn’t say it. And it’s easy to see that possible results are not an argument for your point. But with denying the antecedent, it is possible to make a series of accurate statements, but structure them in such a way that makes for an illogical conclusion.

In this logical fallacy, the speaker starts with a conditional statement, then denies it, and finally arrives at a conclusion though these two. Example: “If Wayne is on the treadmill, he is exercising. Wayne is not on the treadmill. Therefore, Wayne is not exercising.” This is faulty logic since the treadmill is not the only way to exercise. Even if I were NOT exercising, this is still unsound thinking. Of course, an example this transparent would seldom be offered. In fact, other than Answers in Genesis, I know of no entity that speaks in such a manner. But more subtle examples abound. It might come in a form like this: “If the president cared about police officers, he would address the nation about the three killed this week. Yet all the White House offers is silence. So we know he hates cops and their families.”

Denying the antecedent has an equally erroneous twin, affirming the consequent. This switches the order of “if-then” propositions to include the consequent as part of the conditional statement. This is very common among creationists, in some cases being the central or only point. Answers in Genesis asserts that “No evidence can be valid if it contradicts the scriptural record,” then points out that the Big Bang is incompatible with the Bible. It follows by deducing this means the Big Bang could not have happened. This is faulty logic because AIG assumed its original premise to be true without offering supporting evidence.

Another tactic AIG uses is to poison the well. In these instances, the information might be factual, but is irrelevant to the point being made. For example, AIG condemns Old Earth Creationists for not being anti-Big Bang enough when thinking God blew the universe into existence. The organization’s resident astrophysicist, Jason Lisle wrote, “Some professing Christians agree with atheistic astronomers that the stars and planets formed by slow natural processes over billions of years, but stipulate that God’s hand directed these processes.”

That this subset of Christians finds fairly narrow common ground with atheists and scientists has no bearing on whether their beliefs are true. Lisle drops the word “atheistic” only to bias AIG readers against the Old Earth Creationists.

A similar tactic is guilt by association, such as pointing out that Stalin was an atheist. Indeed he was, but he was also white, male, mustachioed, Caucus-born, a former choir boy, a Sagittarius, and the son of a cobbler. Having one common trait with someone does not mean every view or distinction is shared. Nazi Germany was 94 percent Christian, but that is not a sound argument against the religion.

Then we have the appeal to authority, when someone who is an expert in his or her field is assumed to know a lot about whatever the topic is being addressed. I made several attempts to explain science to one of the guys who unfriended me. It was without success, as this man considered every doctor and scientist to be part of an evil cabal that deliberately kept people sick and uninformed. Yet he allowed an exception for Linus Pauling, praising his Nobel Prize in chemistry (an honor he would otherwise belittle), since Pauling had an iconoclastic view on illness and thought Vitamin C could cure everything. The former friend held up Pauling’s accomplishments in chemistry as reason to suppose we should trust his views about an unrelated field. Incidentally, the former friend was also engaged in the logical fallacy of special pleading, where one must carve out an exception to one’s own rule in order to make the argument work. In this case, the pleading was what we can never trust any scientist, unless it’s Pauling.

This is different than relying on someone who has expertise in the area they are addressing. Five years ago I came across a manner for scoring NCAA Tournament pools that used the Fibonacci Method. It purported to be a better way of finding who picked the best tournament, but it used some advanced math, so I was clueless about it. I e-mailed the description to a mathematics Ph.D, who wrote back that the ideas were sound. Since he was an expert in the field, I could reasonably trust his conclusions. This is especially true when consensus is strong. Since 99.8 percent of peer-reviewed papers published over the last 25 years endorse the notion of anthropogenic climate change, this is overwhelming reason to believe it.

This doesn’t mean they or any other experts can never be questioned or be wrong. It means that we need to go where the evidence leads. In the case of climate change, it is backed by a ton of data, peer review, and proper science, and until someone comes up with something better, we go with what the evidence shows.

To be clear, a person with a chemistry degree can make an intelligent, accurate, and original observation about medicine. If they did so, a rebuttal of “Where did you get your medical degree” would be committing a genetic fallacy. But using only a degree, or similar authority, as evidence that they are correct, is erroneous. thinking. 

Finally, I know the mathematics Ph.D. was right about the pool method being a better way to determine a champion because I won it.