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8 logical fallacies that are hard to spot
From "if-by-whiskey" to the McNamara fallacy, being able to spot logical missteps is an invaluable skill.

- A fallacy is the use of invalid or faulty reasoning in an argument.
- There are two broad types of logical fallacies: formal and informal.
- A formal fallacy describes a flaw in the construction of a deductive argument, while an informal fallacy describes an error in reasoning.
In arguments, few things are more frustrating than when you realize that someone is using bad logic, but you can't quite identify what the problem is.
This rarely happens with the more well-known logical fallacies. For example, when someone in an argument starts criticizing the other person's reputation instead of their ideas, most people know that's an ad hominem attack. Or, when someone compares two things to support their argument, but it doesn't make sense, that's a false equivalency. But other fallacies are harder to spot. For example, say you're arguing about politics with a friend, and they say:
"The far-left is crazy. The far-right is violent. That's why the right answers lie the middle."
Sure, it might be true that moderation is the answer. But just because two extremes exist doesn't mean that the truth necessarily lies between those extremes. Put more starkly: If one person says the sky is blue, but someone else says it's yellow, that doesn't mean the sky is green. This is an argument to moderation, or the middle ground fallacy — you hear it a lot from people who are trying to mediate conflicts.
When you find yourself in arguments, it's valuable to be able to spot and, if necessary, call out logical fallacies like this. It can protect you against bad ideas. Check out a few more examples of logical fallacies that can be tough to spot.
Appeal to privacy
When someone behaves in a way that negatively affects (or could affect) others, but then gets upset when others criticize their behavior, they're likely engaging in the appeal to privacy — or "mind your own business" — fallacy. Examples:
- Someone who speeds excessively on the highway, considering his driving to be his own business.
- Someone who doesn't see a reason to bathe or wear deodorant, but then boards a packed 10-hour flight.
Language to watch out for: "You're not the boss of me." "Worry about yourself."
Sunk cost fallacy
When someone argues for continuing a course of action despite evidence showing it's a mistake, it's often a sunk cost fallacy. The flawed logic here is something like: "We've already invested so much in this plan, we can't give up now." Examples:
- Someone who intentionally overeats at an all-you-can-eat buffet just to get their "money's worth"
- A scientist who won't admit his theory is incorrect because it would be too painful or costly
Language to watch out for: "We must stay the course." "I've already invested so much...." "We've always done it this way, so we'll keep doing it this way."
If-by-whiskey
This fallacy is named after a speech given in 1952 by Noah S. "Soggy" Sweat, Jr., a state representative for Mississippi, on the subject of whether the state should legalize alcohol. Sweat's argument on prohibition was (to paraphrase):
If, by whiskey, you mean the devil's brew that causes so many problems in society, then I'm against it. But if whiskey means the oil of conversation, the philosopher's wine, "the stimulating drink that puts the spring in the old gentleman's step on a frosty, crispy morning;" then I am certainly for it.
Note: If-by-whiskey really only becomes a fallacy when it's used to conceal a lack of position, or to dodge a tough question. In Sweat's speech, if-by-whiskey was an effective rhetorical device used to summarize two competing perspectives on alcohol, and to make his position clear.
RationalWiki provides an example of the usual format this fallacy takes:
"If by [noun], you mean [negative descriptors of noun], then of course [statement of lack of support/belief]. If, however, by [noun], you mean [positive descriptors of noun], then [statement of support/belief]."
Slippery slope
This fallacy involves arguing against a position because you think choosing it would start a chain reaction of bad things, even though there's little evidence to support your claim. Example:
- "We can't allow abortion because then society will lose its general respect for life, and it'll become harder to punish people for committing violent acts like murder."
- "We can't legalize gay marriage. If we do, what's next? Allowing people to marry cats and dogs?" (Some people actually made this argument before same-sex marriage was legalized in the U.S.)
Of course, sometimes decisions do start a chain reaction, which could be bad. The slippery slope device only becomes a fallacy when there's no evidence to suggest that chain reaction would actually occur.
Language to watch out for: "If we do that, then what's next?"
"There is no alternative"
A modification of the false dilemma, this fallacy (often abbreviated to TINA) argues for a specific position because there are no realistic alternatives. Former British Prime Minister Margaret Thatcher used this exact line as a slogan to defend capitalism, and it's still used today to that same end: Sure, capitalism has its problems, but we've seen the horrors that occur when we try anything else, so there is no alternative.
Language to watch out for: "If I had a magic wand…" "What else are we going to do?!"
Ad hoc arguments
An ad hoc argument isn't really a logical fallacy, but it is a fallacious rhetorical strategy that's common and often hard to spot. It occurs when someone's claim is threatened with counterevidence, so they come up with a rationale to dismiss the counterevidence, hoping to protect their original claim. Ad hoc claims aren't designed to be generalizable. Instead, they're typically invented in the moment. RationalWiki provides an example:
Alice: "It is clearly said in the Bible that the Ark was 450 feet long, 75 feet wide and 45 feet high."
Bob: "A purely wooden vessel of that size could not be constructed; the largest real wooden vessels were Chinese treasure ships which required iron hoops to build their keels. Even the Wyoming which was built in 1909 and had iron braces had problems with her hull flexing and opening up and needed constant mechanical pumping to stop her hold flooding."
Alice: "It's possible that God intervened and allowed the Ark to float, and since we don't know what gopher wood is, it is possible that it is a much stronger form of wood than any that comes from a modern tree."
Snow job
This fallacy occurs when someone doesn't really have a strong argument, so they just throw a bunch of irrelevant facts, numbers, anecdotes and other information at the audience to confuse the issue, making it harder to refute the original claim. Example:
- A tobacco company spokesperson who is confronted about the health risks of smoking, but then proceeds to show graph after graph depicting many of the other ways people develop cancer, and how cancer metastasizes in the body, etc.
Watch out for long-winded, data-heavy arguments that seem confusing by design.
McNamara fallacy
Named after Robert McNamara, the U.S. secretary of defense from 1961 to 1968, this fallacy occurs when decisions are made based solely on quantitative metrics or observations, ignoring other factors. It stems from the Vietnam War, in which McNamara sought to develop a formula to measure progress in the war. He decided on bodycount. But this "objective" formula didn't account for other important factors, such as the possibility that the Vietnamese people would never surrender.
You could also imagine this fallacy playing out in a medical situation. Imagine a terminal cancer patient has a tumor, and a certain procedure helps to reduce the size of the tumor, but also causes a lot of pain. Ignoring quality of life would be an example of the McNamara fallacy.
Language to watch out for: "You can't measure that, so it's not important."
‘Designer baby’ book trilogy explores the moral dilemmas humans may soon create
How would the ability to genetically customize children change society? Sci-fi author Eugene Clark explores the future on our horizon in Volume I of the "Genetic Pressure" series.
- A new sci-fi book series called "Genetic Pressure" explores the scientific and moral implications of a world with a burgeoning designer baby industry.
- It's currently illegal to implant genetically edited human embryos in most nations, but designer babies may someday become widespread.
- While gene-editing technology could help humans eliminate genetic diseases, some in the scientific community fear it may also usher in a new era of eugenics.
Tribalism and discrimination
<p>One question the "Genetic Pressure" series explores: What would tribalism and discrimination look like in a world with designer babies? As designer babies grow up, they could be noticeably different from other people, potentially being smarter, more attractive and healthier. This could breed resentment between the groups—as it does in the series.</p><p>"[Designer babies] slowly find that 'everyone else,' and even their own parents, becomes less and less tolerable," author Eugene Clark told Big Think. "Meanwhile, everyone else slowly feels threatened by the designer babies."</p><p>For example, one character in the series who was born a designer baby faces discrimination and harassment from "normal people"—they call her "soulless" and say she was "made in a factory," a "consumer product." </p><p>Would such divisions emerge in the real world? The answer may depend on who's able to afford designer baby services. If it's only the ultra-wealthy, then it's easy to imagine how being a designer baby could be seen by society as a kind of hyper-privilege, which designer babies would have to reckon with. </p><p>Even if people from all socioeconomic backgrounds can someday afford designer babies, people born designer babies may struggle with tough existential questions: Can they ever take full credit for things they achieve, or were they born with an unfair advantage? To what extent should they spend their lives helping the less fortunate? </p>Sexuality dilemmas
<p>Sexuality presents another set of thorny questions. If a designer baby industry someday allows people to optimize humans for attractiveness, designer babies could grow up to find themselves surrounded by ultra-attractive people. That may not sound like a big problem.</p><p>But consider that, if designer babies someday become the standard way to have children, there'd necessarily be a years-long gap in which only some people are having designer babies. Meanwhile, the rest of society would be having children the old-fashioned way. So, in terms of attractiveness, society could see increasingly apparent disparities in physical appearances between the two groups. "Normal people" could begin to seem increasingly ugly.</p><p>But ultra-attractive people who were born designer babies could face problems, too. One could be the loss of body image. </p><p>When designer babies grow up in the "Genetic Pressure" series, men look like all the other men, and women look like all the other women. This homogeneity of physical appearance occurs because parents of designer babies start following trends, all choosing similar traits for their children: tall, athletic build, olive skin, etc. </p><p>Sure, facial traits remain relatively unique, but everyone's more or less equally attractive. And this causes strange changes to sexual preferences.</p><p>"In a society of sexual equals, they start looking for other differentiators," he said, noting that violet-colored eyes become a rare trait that genetically engineered humans find especially attractive in the series.</p><p>But what about sexual relationships between genetically engineered humans and "normal" people? In the "Genetic Pressure" series, many "normal" people want to have kids with (or at least have sex with) genetically engineered humans. But a minority of engineered humans oppose breeding with "normal" people, and this leads to an ideology that considers engineered humans to be racially supreme. </p>Regulating designer babies
<p>On a policy level, there are many open questions about how governments might legislate a world with designer babies. But it's not totally new territory, considering the West's dark history of eugenics experiments.</p><p>In the 20th century, the U.S. conducted multiple eugenics programs, including immigration restrictions based on genetic inferiority and forced sterilizations. In 1927, for example, the Supreme Court ruled that forcibly sterilizing the mentally handicapped didn't violate the Constitution. Supreme Court Justice Oliver Wendall Holmes wrote, "… three generations of imbeciles are enough." </p><p>After the Holocaust, eugenics programs became increasingly taboo and regulated in the U.S. (though some states continued forced sterilizations <a href="https://www.uvm.edu/~lkaelber/eugenics/" target="_blank">into the 1970s</a>). In recent years, some policymakers and scientists have expressed concerns about how gene-editing technologies could reanimate the eugenics nightmares of the 20th century. </p><p>Currently, the U.S. doesn't explicitly ban human germline genetic editing on the federal level, but a combination of laws effectively render it <a href="https://academic.oup.com/jlb/advance-article/doi/10.1093/jlb/lsaa006/5841599#204481018" target="_blank" rel="noopener noreferrer">illegal to implant a genetically modified embryo</a>. Part of the reason is that scientists still aren't sure of the unintended consequences of new gene-editing technologies. </p><p>But there are also concerns that these technologies could usher in a new era of eugenics. After all, the function of a designer baby industry, like the one in the "Genetic Pressure" series, wouldn't necessarily be limited to eliminating genetic diseases; it could also work to increase the occurrence of "desirable" traits. </p><p>If the industry did that, it'd effectively signal that the <em>opposites of those traits are undesirable. </em>As the International Bioethics Committee <a href="https://academic.oup.com/jlb/advance-article/doi/10.1093/jlb/lsaa006/5841599#204481018" target="_blank" rel="noopener noreferrer">wrote</a>, this would "jeopardize the inherent and therefore equal dignity of all human beings and renew eugenics, disguised as the fulfillment of the wish for a better, improved life."</p><p><em>"Genetic Pressure Volume I: Baby Steps"</em><em> by Eugene Clark is <a href="http://bigth.ink/38VhJn3" target="_blank">available now.</a></em></p>Octopus-like creatures inhabit Jupiter’s moon, claims space scientist
A leading British space scientist thinks there is life under the ice sheets of Europa.
Jupiter's moon Europa has a huge ocean beneath its sheets of ice.
- A British scientist named Professor Monica Grady recently came out in support of extraterrestrial life on Europa.
- Europa, the sixth largest moon in the solar system, may have favorable conditions for life under its miles of ice.
- The moon is one of Jupiter's 79.
Neil deGrasse Tyson wants to go ice fishing on Europa
<div class="rm-shortcode" data-media_id="GLGsRX7e" data-player_id="FvQKszTI" data-rm-shortcode-id="f4790eb8f0515e036b24c4195299df28"> <div id="botr_GLGsRX7e_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/GLGsRX7e-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/GLGsRX7e-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/GLGsRX7e-FvQKszTI.js"></script> </div>Water Vapor Above Europa’s Surface Deteced for First Time
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="9c4abc8473e1b89170cc8941beeb1f2d"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/WQ-E1lnSOzc?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>Lair of giant predator worms from 20 million years ago found
Scientists discover burrows of giant predator worms that lived on the seafloor 20 million years ago.
Bobbit worm (Eunice aphroditois)
- Scientists in Taiwan find the lair of giant predator worms that inhabited the seafloor 20 million years ago.
- The worm is possibly related to the modern bobbit worm (Eunice aphroditois).
- The creatures can reach several meters in length and famously ambush their pray.
A three-dimensional model of the feeding behavior of Bobbit worms and the proposed formation of Pennichnus formosae.
Credit: Scientific Reports
Beware the Bobbit Worm!
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="1f9918e77851242c91382369581d3aac"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/_As1pHhyDHY?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>FOSTA-SESTA: Have controversial sex trafficking acts done more harm than good?
The idea behind the law was simple: make it more difficult for online sex traffickers to find victims.
Has FOSTA-SESTA really lived up to it's promise of protecting sex trafficking victims - or has it made them easier to target?
- SESTA (Stop Enabling Sex Traffickers Act) and FOSTA (Allow States and Victims to Fight Online Sex Trafficking Act) started as two separate bills that were both created with a singular goal: curb online sex trafficking. They were signed into law by former President Trump in 2018.
- The implementation of this law in America has left an international impact, as websites attempt to protect themselves from liability by closing down the sections of their sites that sex workers use to arrange safe meetings with clientele.
- While supporters of this bill have framed FOSTA-SESTA as a vital tool that could prevent sex trafficking and allow sex trafficking survivors to sue those websites for facilitating their victimization, many other people are strictly against the bill and hope it will be reversed.
What is FOSTA-SESTA?
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="723125b44601d565a7c671c7523b6452"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/WBaqDjPCH8k?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>SESTA (Stop Enabling Sex Traffickers Act) and FOSTA (Allow States and Victims to Fight Online Sex Trafficking Act) were signed into law by former President Trump in 2018. There was some argument that this law may be unconstitutional as it could potentially violate the <a href="https://constitution.congress.gov/constitution/amendment-1/" target="_blank">first amendment</a>. A criminal defense lawyer explains this law in-depth in <a href="https://www.youtube.com/watch?v=RoWx2hYg5uo&t=38s" target="_blank" rel="nofollow">this video</a>. </p><p><strong>What did FOSTA-SESTA aim to accomplish?</strong></p><p>The idea behind the law was simple: make it more difficult for online sex traffickers to find victims. FOSTA-SESTA started as two separate bills that were both created with a singular goal: curb online sex trafficking. Targeting websites like Backpage and Craigslist, where sex workers would often arrange meetings with their clientele, FOSTA-SESTA aimed to stop the illegal sex-trafficking activity being conducted online. While the aim of FOSTA-SESTA was to keep people safer, these laws have garnered international speculation and have become quite controversial. </p><p><a href="https://www.businesswire.com/news/home/20180321006214/en/National-Anti-Trafficking-Coalition-Celebrates-Survivors-Senate-Passes" target="_blank" rel="noopener noreferrer">According to BusinessWire</a>, many people are in support of this bill, including the National Center for Missing and Exploited Children and World Without Exploitation (WorldWE). </p><p>"With the growth of the Internet, human trafficking that once happened mainly on street corners has largely shifted online. According to the National Center for Missing & Exploited Children, 73 percent of the 10,000 child sex trafficking reports it receives from the public each year involve ads on the website Backpage.com."</p><p>As soon as this bill was <a href="https://www.pivotlegal.org/sesta_fosta_censoring_sex_workers_from_websites_sets_a_dangerous_precedent" target="_blank" rel="noopener noreferrer">signed into law</a>, websites where sex workers often vetted and arranged meetings with their clients could now be held liable for the actions of the millions of people that used their sites. This meant websites could be prosecuted if they engaged in "the promotion or facilitation of prostitution" or "facilitate traffickers in advertising the sale of unlawful sex acts with sex trafficking victims." </p><p><strong>The bill's effects were felt around the world — from Canadians being unhappy with the impact of this American bill to U.K. politicians considering the implementation of similar laws in the future.</strong> </p><p>Heather Jarvis, the program coordinator of the Safe Harbour Outreach Project (SHOP), which supports sex workers in the St. John's area, <a href="https://www.cbc.ca/news/canada/newfoundland-labrador/heather-jarvis-website-shutdown-1.4667018" target="_blank" rel="noopener noreferrer">explained to CBC in an interview</a> that the American bill is impacting everyone, everywhere: "When laws impact the internet — the internet is often borderless — it often expands across different countries. So although these are laws in the United States, what we've seen is they've been shutting down websites in Canada and other countries as well."</p><p>Jarvis suggests in her interview that instead of doing what they aimed to do with the bill and improving the safety of victims of sex trafficking or sexual exploitation, the website shutdowns are actually making sex workers less safe. </p><p>While <a href="https://gizmodo.com/the-uk-wants-its-own-version-of-fosta-sesta-that-could-1827420794" target="_blank" rel="noopener noreferrer">one U.K. publication</a> refers to FOSTA-SESTA as "well-intentioned but ultimately deeply-flawed laws," it also mentions that politicians in the United Kingdom are hoping to pursue similar laws in the near future. </p>Has FOSTA-SESTA done more harm than good?
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTUxMzY5Ny9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY2ODUyNDc4OX0.dSEEzcflJJUTnUCFmuwmPAIA0f754eW7rN8x6L7fcCc/img.jpg?width=1245&coordinates=-68%2C595%2C-68%2C595&height=700" id="69d99" class="rm-shortcode" data-rm-shortcode-id="734759fa254b5a33777536e0b4d7b511" data-rm-shortcode-name="rebelmouse-image" alt="sex worker looking online for a job" data-width="1245" data-height="700" />Is this really going to help, or is this bill simply pushing sex work and sex-related content further into the dark?
Credit: Евгений Вершинин on Adobe Stock
<p>While <a href="https://www.businesswire.com/news/home/20180321006214/en/National-Anti-Trafficking-Coalition-Celebrates-Survivors-Senate-Passes" target="_blank">supporters of this bill</a> have framed FOSTA-SESTA as a vital tool that could prevent sex trafficking and allow sex trafficking survivors to sue those websites for facilitating their victimization, many other people are strictly against the bill and hope it will be reversed.</p><p><strong>One of the biggest problems many people have with this bill is that it forces sex workers into an even more dangerous situation, which is quite the opposite of what the bill had intended to do.</strong> </p><p>According to <a href="https://www.theglobeandmail.com/canada/article-anti-trafficking-activists-cheer-but-sex-workers-bemoan-shutdown-of/" target="_blank" rel="noopener noreferrer">Globe and Mail</a>, there has been an upswing in pimps sending sex workers messages that promise work - which puts sex workers on the losing end of a skewed power-dynamic, when before they could attempt to safely arrange their own meetings online. </p><p><strong>How dangerous was online sex work before FOSTA-SESTA? </strong></p><p><a href="https://www.beyond-the-gaze.com/wp-content/uploads/2018/01/BtGbriefingsummaryoverview.pdf" target="_blank" rel="noopener noreferrer">The University of Leicester Department of Criminology</a> conducted an online survey that focused on the relative safety of internet-based sex work compared with outdoor sex work. According to the results, 91.6 percent of participants had not experienced a burglary in the past 5 years, 84.4 percent had not experienced physical assault in the same period, and only 5 percent had experienced physical assault in the last 12 months. </p><p><a href="https://www.pivotlegal.org/sesta_fosta_censoring_sex_workers_from_websites_sets_a_dangerous_precedent" target="_blank" rel="noopener noreferrer">PivotLegal</a> expresses concerns about this: "It is resoundingly clear, both from personal testimony and data, that attacking online sex work is an assault on the health and safety of people in the real world. In a darkly ironic twist, SESTA/FOSTA, legislation aimed at protecting victims of and preventing human trafficking for the purposes of sexual exploitation, will do the exact opposite."</p><p><strong>Websites are also being hypervigilant (and censoring more content than needed) because they can't possibly police every single user's activity on their platform.</strong> </p><p>Passing this bill meant any website (not just the ones that are commonly used by sex traffickers) could be held liable for their user's posts. Naturally, this saw a general "tightening of the belt" when it came to what was allowed on various platforms. In late 2018, shortly after the FOSTA-SESTA bill was passed, companies like Facebook slowly began to alter their terms and conditions to protect themselves. </p><p>Facebook notably added sections that express prohibited certain sexual content and messages:</p><p style="margin-left: 20px;"><em>"Content that includes an implicit invitation for sexual intercourse, which can be described as naming a sexual act and other suggestive elements including (but not limited to):</em></p><p style="margin-left: 20px;"><em>– vague suggestive statements such as: 'looking forward to an enjoyable evening'</em></p><p style="margin-left: 20px;"><em>– sexual use of language […]</em></p><p style="margin-left: 20px;"><em>– content (self-made, digital or existing) that possibly portrays explicit sexual acts or a suggestively positioned person/suggestively positioned persons."<br><br> </em></p><p>Additionally, sections like this were also added, prohibiting things that could allude to sexual activity: </p><p style="margin-left: 20px;"><em>"Content in which other acts committed by adults are requested or offered, such as:</em></p><p style="margin-left: 20px;"><em>– commercial pornography</em></p><p style="margin-left: 20px;"><em>– partners that share fetishes or sexual interests"</em></p><p>Facebook wasn't the only website to crack down on their policies — the Craigslist classifieds section being removed and Reddit banned quite a large number of sex-worker related subreddits. </p><p><strong>Is FOSTA-SESTA really helpful?</strong> </p><p>This is the question many people are facing with the FOSTA-SESTA acts being passed just a few years ago. Is this really going to help, or is this bill simply pushing sex work and sex-related content further into the dark? Opinions seem to be split down the middle on this — what do you think?</p>What is the ‘self’? The 3 layers of your identity.
Answering the question of who you are is not an easy task. Let's unpack what culture, philosophy, and neuroscience have to say.
