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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."
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]."
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."
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.
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."
Northwell Health is using insights from website traffic to forecast COVID-19 hospitalizations two weeks in the future.
- The machine-learning algorithm works by analyzing the online behavior of visitors to the Northwell Health website and comparing that data to future COVID-19 hospitalizations.
- The tool, which uses anonymized data, has so far predicted hospitalizations with an accuracy rate of 80 percent.
- Machine-learning tools are helping health-care professionals worldwide better constrain and treat COVID-19.
The value of forecasting<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTA0Njk2OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyMzM2NDQzOH0.rid9regiDaKczCCKBsu7wrHkNQ64Vz_XcOEZIzAhzgM/img.jpg?width=980" id="2bb93" class="rm-shortcode" data-rm-shortcode-id="31345afbdf2bd408fd3e9f31520c445a" data-rm-shortcode-name="rebelmouse-image" data-width="1546" data-height="1056" />
Northwell emergency departments use the dashboard to monitor in real time.
Credit: Northwell Health<p>One unique benefit of forecasting COVID-19 hospitalizations is that it allows health systems to better prepare, manage and allocate resources. For example, if the tool forecasted a surge in COVID-19 hospitalizations in two weeks, Northwell Health could begin:</p><ul><li>Making space for an influx of patients</li><li>Moving personal protective equipment to where it's most needed</li><li>Strategically allocating staff during the predicted surge</li><li>Increasing the number of tests offered to asymptomatic patients</li></ul><p>The health-care field is increasingly using machine learning. It's already helping doctors develop <a href="https://care.diabetesjournals.org/content/early/2020/06/09/dc19-1870" target="_blank">personalized care plans for diabetes patients</a>, improving cancer screening techniques, and enabling mental health professionals to better predict which patients are at <a href="https://healthitanalytics.com/news/ehr-data-fuels-accurate-predictive-analytics-for-suicide-risk" target="_blank" rel="noopener noreferrer">elevated risk of suicide</a>, to name a few applications.</p><p>Health systems around the world have already begun exploring how <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7315944/" target="_blank" rel="noopener noreferrer">machine learning can help battle the pandemic</a>, including better COVID-19 screening, diagnosis, contact tracing, and drug and vaccine development.</p><p>Cruzen said these kinds of tools represent a shift in how health systems can tackle a wide variety of problems.</p><p>"Health care has always used the past to predict the future, but not in this mathematical way," Cruzen said. "I think [Northwell Health's new predictive tool] really is a great first example of how we should be attacking a lot of things as we go forward."</p>
Making machine-learning tools openly accessible<p>Northwell Health has made its predictive tool <a href="https://github.com/northwell-health/covid-web-data-predictor" target="_blank">available for free</a> to any health system that wishes to utilize it.</p><p>"COVID is everybody's problem, and I think developing tools that can be used to help others is sort of why people go into health care," Dr. Cruzen said. "It was really consistent with our mission."</p><p>Open collaboration is something the world's governments and health systems should be striving for during the pandemic, said Michael Dowling, Northwell Health's president and CEO.</p><p>"Whenever you develop anything and somebody else gets it, they improve it and they continue to make it better," Dowling said. "As a country, we lack data. I believe very, very strongly that we should have been and should be now working with other countries, including China, including the European Union, including England and others to figure out how to develop a health surveillance system so you can anticipate way in advance when these things are going to occur."</p><p>In all, Northwell Health has treated more than 112,000 COVID patients. During the pandemic, Dowling said he's seen an outpouring of goodwill, collaboration, and sacrifice from the community and the tens of thousands of staff who work across Northwell.</p><p>"COVID has changed our perspective on everything—and not just those of us in health care, because it has disrupted everybody's life," Dowling said. "It has demonstrated the value of community, how we help one another."</p>
A leading British space scientist thinks there is life under the ice sheets of Europa.
- 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>
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A fairly old idea, but a really good one, is about to hit the store shelves.
- The idea of growing food from CO2 dates back to NASA 50 years ago.
- Two companies are bringing high-quality, CO2-derived protein to market.
- CO2-based foods provide an environmentally benign way of producing the protein we need to live.
The basic idea<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTQ0NTM3Ny9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxOTc4NzE1MX0.qxFjO6GkVVEjS_VEKy4pIkrmv-gknDbBgTHourWFUcc/img.jpg?width=980" id="20397" class="rm-shortcode" data-rm-shortcode-id="fa52d13cbf404456d0a5be77ff2e091e" data-rm-shortcode-name="rebelmouse-image" data-width="1089" data-height="898" />
Credit: Big Think<p> The basic mechanism for deriving food from CO<sup>2</sup> involves a fairly simple closed-loop system that executes a process over and over in a cyclical manner, producing edible matter along the way. In space, astronauts produce carbon dioxide when they breathe, which is then captured by microbes, which then convert it into a carbon-rich material. The astronauts eat the material, breathe out more CO<sup>2</sup>, and on and on. On Earth, the CO<sup>2</sup> is captured from the atmosphere. </p>
Drawing first breath<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTQ0NTM3NS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NDQyNjAwMH0.3b4FuXhLwAqGtXzFu2dw8Gec6phKp3bxkajLOJKFOYE/img.jpg?width=980" id="03d4b" class="rm-shortcode" data-rm-shortcode-id="a5131ef8090c05af83989905de39c53d" data-rm-shortcode-name="rebelmouse-image" data-width="1000" data-height="780" />
Credit: NASA<p> NASA's investigation into using CO<sup>2</sup> for food production began with a 1966 report written by R. B. Jagow and R. S. Thomas and published by Ames Research Center. The nine-chapter report was called "<a href="https://ntrs.nasa.gov/citations/19670025254" target="_blank">The Closed Life-Support System</a>." Each chapter contained a proposal for growing food on long missions. </p><p> Chapter 8, written by J. F. Foster and J. H. Litchfield of the Battelle Memorial Institute in Columbus, Ohio, proposed a system that utilized a hydrogen-fixing bacteria, <em><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC247306/" target="_blank">Hydrogenomonas</a></em>—NASA had been experimenting with the bacteria for several years at that point—and recycled CO<sup>2</sup> in a compact, low-power, closed-loop system. The system would be able to produce edible cell matter in way that "should then be possible to maintain continuous cultures at high efficiencies for very long periods of time." </p><p> At the time, extended missions that would benefit from such a system were off in the future. </p><p> In 2019, and with its eye toward upcoming Mars missions, NASA returned to the idea, sponsoring the <a href="https://www.nasa.gov/directorates/spacetech/centennial_challenges/co2challenge/challenge-announced.html" target="_blank">CO2 Conversion Challenge</a>, "seeking novel ways to convert carbon dioxide into useful compounds." Phase 1 of the contest invited proposals for processes that could "convert carbon dioxide into glucose in order to eventually create sugar-based fuel, food, medicines, adhesives and other products." </p><p> In May 2109, NASA announced the <a href="https://www.nasa.gov/spacetech/centennial_challenges/co2challenge/winning-teams-design-systems-to-convert-carbon-dioxide-into-something-sweet.html" target="_blank">winners</a> of Phase 1. The space agency concluded acceptance of <a href="https://www.co2conversionchallenge.org/#about" target="_blank">Phase 2</a> entries on December 4, 2020.</p>
Approaching the Finnish line<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTQ0NTM2Mi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0MTkyNDYzNH0.02upErPyJQO5YvKEmk-Hqrve4Prg_5cZHMaXBFCAbOQ/img.jpg?width=980" id="e593a" class="rm-shortcode" data-rm-shortcode-id="e2d8de8068bcd9f497f284d2fafc7b9c" data-rm-shortcode-name="rebelmouse-image" data-width="1400" data-height="930" />
Credit: Solar Foods<p> We've <a href="https://bigthink.com/technology-innovation/protein-from-air?rebelltitem=1#rebelltitem1" target="_self">written previously</a> about <a href="https://solarfoods.fi" target="_blank">Solar Foods</a>, a company backed by the Finnish government who <a href="https://solarfoods.fi/our-news/business-finland-greenlights-solar-foods-e8-6m-project/" target="_blank">recently invested</a> €4.3 million to help complete the company's €8.6 million commercialization of their nutrient-rich CO<sup>2</sup>-based protein powder, <a href="https://solarfoods.fi/solein/" target="_blank">Solein</a>. The company anticipates Solein will provide protein to some 400 million meals by 2025, and has so far developed 20 different food products from it. </p>
In the air tonight<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTQ0NTM2NC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY3MjQ4MjgxMH0.6VP4Aw_JzTG7lnuQeXiUnpAppJTdnsxVTuPdiUiW9oI/img.jpg?width=980" id="4b5a0" class="rm-shortcode" data-rm-shortcode-id="9e683650fd8175592794dff6ae0799bf" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="894" />
Air Protein taco
Credit: Air Protein<p> Another player, <a href="https://www.airprotein.com" target="_blank">Air Protein</a>, is based in California's Bay Area and is also bringing to market their own CO<sup>2</sup> protein named after the company. The company <a href="https://www.prnewswire.com/news-releases/air-protein-introduces-the-worlds-first-air-based-food-300955972.html" target="_blank">describes</a> it as a "nutrient-rich protein with the same amino acid profile as an animal protein and packed with crucial B vitamins, which are often deficient in a vegan diet." </p><p> The company recently <a href="https://www.greenqueen.com.hk/air-protein-bags-us32m-in-series-a-to-commercialise-climate-friendly-meat/" target="_blank">secured $32 million</a> in venture-capital funding. </p><p> Although Air Protein is actually flour—like Solein—the company is positioning Air Protein as offering "the first air-based meat," while Solein was announced first, and there's <a href="https://www.afr.com/life-and-luxury/food-and-wine/company-that-makes-meat-out-of-air-attracts-big-backers-20210108-p56sk0" target="_blank" rel="noopener noreferrer">no public timetable</a> yet for the arrival of Air Protein products on store shelves. In any event, non-animal "meats" are a <a href="https://bigthink.com/technology-innovation/whopper" target="_self">hot market</a> these days with the success of Beyond Burger and Impossible Foods cruelty-free meat substitutes. </p>
Striking oil<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTQ0NTM2Ny9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1MzE3NjA3NH0.1o05KthbzT9JokT7-0UzWDq4MiLIfXJIGfPddhLNKqk/img.jpg?width=980" id="a45ef" class="rm-shortcode" data-rm-shortcode-id="143316dcc3691fcce024e83a6cbaca3f" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="959" />
Deforestation for palm oil
Credit: whitcomberd/Adobe Stock<p> Though Air Protein's promotional materials emphasize meat substitutes that will be derived from their flour, a <a href="https://youtu.be/c8WMM_PUOj0" target="_blank">TED Talk</a> by company co-founder Lisa Dyson reveals another Air Protein product that could arguably have an even greater impact by potentially eliminating the need for palm oil and the deforestation it requires — their CO<sup>2</sup> process can produce oils.</p><p><span></span>The company has already created a citrus-like oil that can be used for fragrances, flavoring, as a biodegradable cleaner, and "even as a jet fuel." Perhaps more excitingly, the company has made another oil that's similar to palm oil. Since palm trees are the <a href="https://www.ran.org/palm_oil_fact_sheet" target="_blank">crop most responsible</a> for the decimation of the world's rain forests, an environmentally benign replacement for it would be a very big deal. Dyson also notes that their oils could substitute morally problematic coconut oil, whose harvesting has lately been reported to often involve the abuse of macaque monkeys.</p>