explain xkcd - User contributions [en]

2929: Good and Bad Ideas

2025-02-18T15:42:52Z

162.158.154.206: /* Explanation */

{{comic
| number = 2929
| date = May 6, 2024
| title = Good and Bad Ideas
| image = good_and_bad_ideas_2x.png
| imagesize = 595x522px
| noexpand = true
| titletext = While it seemed like a fun prank at the time, I realize my prank fire extinguishers full of leaded gasoline were a mistake.
}}

==Explanation==
This is a scatter plot comparing how good an idea sounds to how good the idea is. For example, leaded gasoline sounded like a good idea due to its anti-knocking effects, but is a bad idea due to lead toxicity. Fake prank fire extinguishers both sound bad and ''are'' bad, as they can make a dangerous situation worse. Putting mold on infections sounds like a bad idea, but some molds, like ones containing penicillin, have helpful antibiotic effects.

The title text combines leaded gasoline and a fake prank fire extinguisher into something worse than either. The fire extinguisher is fake and releases flammable material onto the fire, and there is additional lead toxicity.

===Table of the entries===
{| class="wikitable sortable"

|-
! Idea !! What it means !! How good it sounds !! How good it actually is !! Explanation
|-
|{{w|Leaded gasoline}}||Adding {{w|Tetraethyllead|tetraethyl lead}} as an antiknocking agent to allow for increased performance||data-sort-value="+65%"|65%||data-sort-value="-95%"|-95%||Leaded gasoline was introduced in the early 1920s to allow higher pressures and temperatures in an engine without causing {{w|Engine_knocking|detonation (knocking)}}, allowing for increased fuel efficiency and engine performance; it also works to prevent engine valve wear. In essence, it artificially raises the {{w|octane rating}} of the fuel, reducing the need for fuel refinement, thus reducing waste and/or expense. Lead, however, is both toxic and bioaccumulative, meaning that lead released into the air over decades built up to harmful levels in people (as well as other animals) and almost certainly contributed to a host of health issues. Some scientists even hypothesise that {{w|Lead–crime hypothesis|crime levels are influenced by lead exposure}}. (It should be noted that this only "[sounded] like a good idea" due to deliberate campaigns to obscure the known dangers).
|-
|{{w|Bloodletting}}||Releasing "bad blood" from the veins||data-sort-value="-90%"|-90%||data-sort-value="-100%"|-100%||You need (most of) your blood. Losing [https://www.ncbi.nlm.nih.gov/books/NBK542273/ more than 15%] of a person's total blood volume results in adverse effects. Bloodletting was performed as a medical procedure for at least 2000 years until the 19th century. The idea was to withdraw blood to balance the body's "humors". Despite this long history, the notion that bleeding someone is bad now seems like basic common sense, and it's now well-understood that blood-letting (outside of {{what if|98|certain rare and specific cases}}) does no good, causes significant harm and quite certainly causes many deaths.
|-
|{{w|Asbestos}}||Mineral which does not burn, tolerates extremely high temperatures and forms small fibers. These qualities make it excellent for insulation and fire protection||data-sort-value="+90%"|90%||data-sort-value="-80%"|-80%||Asbestos was used extensively in ships and buildings throughout most of the 20th century. Unfortunately, the microscopic fibers that make up asbestos greatly increase the risk of {{w|Asbestosis|lung disease}} and cancer when inhaled, causing its use to be banned in most countries.
|-
|Extension cords with prongs on both ends||allows easy connection between 2 female connectors||data-sort-value="+5%"|~0%||data-sort-value="-80%"|-80%||Prongs on both ends would make it easier to plug the extension cord in on either side. But once plugged into an outlet, the other end becomes a serious shock hazard, as seen in [https://www.youtube.com/watch?v=L08LjkN1k70 this Backyard Scientist video]. Short circuits (both ends connected to outlets supplying power) would be much more likely, resulting in more sparks, fires and damage to wiring. Double-ended cords are also sometimes used as an especially dangerous way to feed power from a generator into an outlet, introducing a shock hazard to any utility workers attempting to restore power.
|-
|Stair kayaking||Riding down a flight of stairs in a {{w|kayak}}||data-sort-value="-60%"|-60%||data-sort-value="-75%"|-75%|| Stair kayaking is a stunt where a person positions a kayak at the top of a flight of stairs and then, using their paddle to push off, [https://youtu.be/46BjHAxgddU?t=154 rides the kayak down the stairs]. This poses significant easily foreseeable risks of injury or death, as well as being very bad for the kayak, which is designed to ride on {{w|Kayak|water}}, not stairs.{{Citation needed}}
|-
|Fake prank fire extinguishers||A “fake prank” fire extinguisher would be something that appears to be a prank fire extinguisher, but is actually a real fire extinguisher. However, Randall appears to mean using a fake fire extinguisher as a prank. Intentionally placing empty or otherwise non-functional {{w|fire extinguisher|fire extinguishers}} as a {{w|practical joke}}.||data-sort-value="-105%"|-100%||data-sort-value="-85%"|-85%|| The idea of placing fake fire extinguishers as a prank, presumably so that a person who thinks they are grabbing a real fire extinguisher will instead find a decoy, sounds, and indeed would be, very dangerous and potentially life-threatening for many people. In the United States, (and presumably most countries), this would also be a felony in most, if not all, jurisdictions. This exact scenario was depicted in the 2001/Season 3 Christmas episode of Family Guy, where Brian failed to put out a fire because the fire extinguisher shot fake snakes instead, acting as further fuel to the fire. An example of a similar situation, although not intended as a prank, can be found [https://twitter.com/ThatSamWinkler/status/1657154071051239424 here].
The title text expands this idea by having the prank fire extinguishers filled with (leaded) gasoline. This is literally adding fuel to the fire.
|-
|Always saying what you think||...regardless of the feelings of others or other considerations||data-sort-value="+65%"|65%||data-sort-value="-60%"|-60%||Openness and honesty are seen as positive character traits in people. Taking it to the extreme of ''always'' telling people what you think has been {{w|Radical_honesty|espoused by some}}, but can lead to awkward, unpleasant or dangerous situations. It may harm your relationship with the other person if they don't like what you think, or they may reply without concern for ''your'' feelings or other considerations. Keeping negative thoughts to yourself or telling "white lies" can be considered a better alternative in some situations.
Unrestrictively saying what you think to somebody in power (a boss, soldier, dictator, drunk) can negatively impact your earning potential, health or freedom, even if you have a point. Or else, on the offchance that your (first) thoughts are less correct, [https://quoteinvestigator.com/2010/05/17/remain-silent/ "Better to remain silent and be thought a fool than to speak and to remove all doubt."]
|-
|Replying to spammers||Clicking on the "Reply" button from {{w|spam email}}s and writing (and sending) a reply (or worse, clicking on the links in these emails)||data-sort-value="-50%"|-50%||data-sort-value="-50%"|-50%||At best, you confirm your email address and identify yourself as someone likely to respond to such messages and so encourage the spammers to deluge you with more messages. At worst, the spammer may extract sensitive information about you, make you a victim of a scam or gain control of your computer.
|-
|{{w|Solar car}}s||Having {{w|Solar panel|solar panels}} on the car's surface (mostly hood and roof) for power generation||data-sort-value="+95%"|95%||data-sort-value="-35%"|-35%||Powering electric vehicles with solar panels seems like an excellent idea: it would provide power with no increased land use, and theoretically could allow a vehicle to operate indefinitely without being fueled or charged. However, such vehicles would require power storage (due to power requirements, weather conditions, shade from roadside features and nighttime driving), adding significant weight. Adding solar panels to a plug-in or hybrid vehicle would add cost, weight, manufacturing complexity and maintenance requirements. Solar panels on moving cars are less efficient than in stationary installations, where they can be aimed at the Sun, and subject to damage from both collisions and road debris; even without these problems, the size of automobiles relative to their power requirements would sharply limit the car's range (unless it was a normal electric vehicle with supplemental solar panels). Solar cars do exist (the {{w|World Solar Challenge}} is a competition for such cars), but as a practical form of transportation, the negatives likely outweigh the positives. See also [[1924: Solar Panels]].
|-
|{{w|Heelys|Heelies}}||Heelys are shoes with an inline skate wheel built in the sole, at the heel. ||data-sort-value="+25%"|25%||data-sort-value="-40%"|-40%||Heelys allow the wearer (usually children) to shift between normal walking and rolling like being on skates. This sounds like fun but [https://abcnews.go.com/Health/Exercise/story?id=3242181&page=1 has been suggested] to be a potentially significant injury risk.
|-
|{{w|Prequel|Prequels}}||A work of fiction (often a movie) telling the "story before the story" of another work.||data-sort-value="+75%"|75%||data-sort-value="-15%"|-15%||More of a good story sounds great on the surface, and audiences who are invested in a set of characters and/or a setting often love the idea of finding out what led up to certain events. But there are several pitfalls. Spin-offs of a popular property are often low-quality cash grabs. Prequels, specifically, are constrained by the fact that they have to lead to the story that's already been released, which can lead to contrived storytelling. There's less room for suspense, since the future of the storyline has already been established. There's a tendency to invent or fill in detailed backstories, which can undermine character arcs and/or destroy the mystery and nuance of certain characters. And, since they tend only to be made where the original is already well-received, regression to the mean tends to mean they are more likely than not to fail to live up to expectations. Prequels can be good, but there are a lot of ways they can go wrong.
|-
|Transitions® lenses||A brand name for {{w|Photochromic_lens|photochromic lenses}} in glasses or contacts, which get darker (like sunglasses) in bright light.||data-sort-value="+30%"|30%||data-sort-value="-20%"|-20%||Photochromic lenses are clear lenses that darken when exposed to UV light, then turn clear again when the UV is removed. The advantage is that wearers of glasses don't need to have separate (prescription) sunglasses or contacts. However, the process is relatively slow (about a minute) so not so useful when there is a quick succession of shade and bright light, as in a forest or when driving. If used in a car, the windscreen filters out UV light to some degree, which prevents the glasses from darkening as required. Finally, the process is temperature dependent, so in hot weather the glasses don't become as dark, and in cold weather they might stay dark for too long.

Additionally, the following should be considered. UV-conscious people protect their face against UV light, so the skin doesn't form wrinkles and ages slower. Sunscreen is difficult to apply around eyes without getting the substance on eyeballs (cosmetic substances should not get there{{Citation needed}}). One of the reasons behind wearing sunglasses may be to protect skin around eyes from forming so called crow's feet. Under UV-filtering sunglasses, UV-activated transitions contact lenses will not darken defeating their purpose. At the same time transitions contacts are typically at least twice as expensive as the regular ones.
|-
|Cutting pizza in squares||Cutting (a presumably round) pizza in squares||data-sort-value="-25%"|-25%||data-sort-value="-20%"|-20%||Most people cut pizza into wedges and hold it by the crust. Cutting it into squares could allow for more pieces to be shared, if the resulting wedges would be too thin to be practical. However, pieces near the center will have no crust to hold it by, getting cheese and sauce all over your fingers. Cuts around the edge will probably leave smaller leftover scraps which are mostly crust. While hardly a disaster like the other items in its quadrant, square pizza pieces are just not very useful and rather inefficient. Cutting a rectangular pizza into squares might not suffer from the problems above, but, unless the pizza itself is square and cut only into four squares, some people will end up with a higher crust-to-topping ratio than others. Cutting a round pizza into squares is popular in Chicago and is sometimes called tavern-style or party-cut and some<sup><nowiki>[</nowiki>''{{w|Wikipedia:Manual_of_Style/Words_to_watch#Unsupported_attributions|who?}}''<nowiki>]</nowiki></sup> [https://www.bonappetit.com/story/real-chicago-pizza-tavern-style consider it the real Chicago style pizza] [https://destinationeatdrink.com/the-real-chicago-style-pizza-isnt-deep-dish/ rather than deep dish pizza].{{Dubious}}
|-
|{{w|Project Orion (nuclear propulsion)|Project Orion}}||Study by the U.S. government looking into nuclear pulse propulsion for spacecraft.||data-sort-value="-95%"|-95%||data-sort-value="-25%"|-25%||Using repeated nuclear explosions to generate motion sounds bad for both the spacecraft and everything else, especially with a ground launch, but there are ways to address a lot of the concerns, so it isn't as bad as it sounds. Project Orion's theorized specific impulse and thrust would also be far higher than anything chemical rockets can accomplish. The efficiency of Project Orion is extremely low, however, and the {{w|ablation}} issues are extremely difficult to overcome.

See also [[2423: Project Orion]].
|-
|{{w|Soup}}||Soup||data-sort-value="0%"|~0%||data-sort-value="0%"|~0%||Soup is probably one of the oldest foods created by prehistoric cooks. Many people enjoy it, though some consider many soups somewhat lacking as a meal on their own, or boring.
|-
|{{w|Washer-dryer|Combo washer dryers}}||A device that combines a washing machine and laundry dryer||data-sort-value="+80%"|80%||data-sort-value="+20%"|20%||Better at space efficiency, but worse at each task than separate devices and unable to do both tasks in parallel (useful when you have more than one batch of laundry).
|-
|Cutting sandwiches diagonally||Cutting sandwiches made with rectangular sliced bread diagonally||data-sort-value="+30%"|30%||data-sort-value="+20%"|20%||[https://www.popularmechanics.com/science/math/a32690399/triangles-rectangles-best-way-cut-sandwich-math/ Generally] [https://www.npr.org/2009/11/28/120914097/rectangles-vs-triangles-the-great-sandwich-debate regarded] as the superior way to slice a sandwich, providing more aesthetically pleasing display of the contents, better support in the hand and fewer all-crust bites.
|-
|{{w|Diverging diamond interchange}}s||Road junction where the two (sets of) lanes cross over to switch sides (so if you normally drive on the right, now you drive on the left), then switch back to normal after the junction||data-sort-value="-30%"|-30%||data-sort-value="+15%"|15%||Highway engineers believe the shape improves safety and traffic flow through the interchange because switching to the other side facilitates merging to and from the other road in the junction. However, the shape appears to be insanity to an unfamiliar driver, who may assume that driver confusion would lead to increased accidents.
|-
|Toasting sandwiches||Making a sandwich first and then cooking it, as in a dedicated {{w|Pie_iron|sandwich toaster}}, a {{w|toaster oven|toaster oven}}, frying pan or under a grill.||data-sort-value="+45%"|45%||data-sort-value="+50%"|50%||The grilled cheese sandwich is a familiar form to most people, and many other sandwiches are improved by toasting as a final step. Doing so makes the sandwich warm, while also making the bread crisp and crunchy, while often melting or softening the fillings, which provides contrasting textures that many find pleasing. Other sandwiches, such as the {{w|western sandwich|Western}} or {{w|club sandwich|club}} are prepared using toast. The {{w|peanut butter, banana and bacon sandwich|Elvis}} is a specific case of a sandwich that normally wouldn't be toasted, but is improved by it - peanut butter, bacon, banana and jelly, with the assembly lightly fried.
|-
|{{w|Crumple zone}}s||Areas of a car that are designed to deform in a controlled way in case of a crash. ||data-sort-value="-55%"|-55%||data-sort-value="+55%"|55%||Most people's intuition would be that stronger cars are safer, and intending parts of a vehicle to collapse ''by design'' might seem crazy. But engineered crumple zones are designed to gradually absorb the kinetic energy in a vehicle collision and protect the passenger cabin. The result is that the occupants experience less intense deceleration and ideally without the damage significantly compressing the shell around them. This significantly reduces the danger of injury or death from higher speed crashes.
|-
|{{w|Sliced bread}}||Bread, sliced by the baker before packaging for sale||data-sort-value="+95%"|95%||data-sort-value="+65%"|65%||It's far more convenient for making sandwiches or toast, but unfortunately pre-sliced bread will go stale faster and some applications may be better off thicker or thinner than the slices provided. Sliced bread is often used as a comparator for how good something is, using the phrase 'the best thing since sliced bread'.
|-
|{{w|Pizza}}||Pizza - a dish made by arranging ingredients on thin dough and cooking it, usually cut radially||data-sort-value="+55%"|55%||data-sort-value="+75%"|75%||Pizza is a widely popular dish throughout much of the world, uncontroversial {{w|Anchovies_as_food|except}} {{w|Pineapple|certain}} [https://www.taste.com.au/recipes/nutty-choc-pizza-fresh-berries/2c0220a4-8463-45ff-b2ba-ac7e5012a006 toppings].
|-
|Eating citrus fruit while at sea||Having a supply of {{w|citrus fruit}} on long sea journeys, especially during the {{w|Age of Sail}} ||data-sort-value="0%"|~0%||data-sort-value="+75%"|75%||For a long time, {{w|Scurvy|scurvy}} was a danger to sailors, who generally subsisted on a monotonous diet of shelf-stable foods with low vitamin content while on long voyages. Most citrus fruits are rich in vitamin C, which prevents scurvy. Eating orange or lemons doesn't seem like a significant activity one way or the other, but it's an easy way to prevent a disease that causes serious ill-health and possibly a painful death.
|-
|Putting mold on infections||Seemingly a reference to the ancient practice of pressing moldy bread against infected wounds||data-sort-value="-110%"|-100%||data-sort-value="+60%"|60%||While this sounds like a good way to get a fungal infection, with the correct mold this is a primitive way to obtain an antibiotic. Certain fungi naturally produce antibiotic substances, and this is where humans discovered {{w|penicillin}}.
|-
|Wheels on luggage||Some luggage bags have small wheels inset on their frame and a carrying handle.||data-sort-value="+100%"|100%||data-sort-value="+90%"|90%||A relatively simple fitting for rigid or semi-rigid luggage that substantially eases its transport over long distances on flat surfaces such as travel terminals.
|-
|{{w|Heat pump}}s||A technology that moves heat energy from a cold area to a warm area, most familiar as the technology that keeps a refrigerator cold. It can be used to heat a home interior in winter or cool it in summer.||data-sort-value="+55%"|55%||data-sort-value="+95%"|95%||Unlike traditional furnaces, heat pumps do not generate heat (beyond a small overhead). Instead, they move existing thermal energy from a coolable environment across to a warmable one. This allows a space to be heated with significantly less energy use than a furnace or resistance heater that generates heat directly from chemical or electrical energy. Because these units are usually operated by electricity, they can provide heating with renewable energy (potentially using {{w|thermal energy storage}} for load-shifting), reduce or eliminate the need for natural gas connections and prevent several risks that come with traditional furnaces (such a carbon monoxide leaks and fires). In addition, heat pumps can operate in the reverse direction as air conditioners, so a single unit can be designed to both heat and cool a building. It sounds like a good idea and works out better than expected in real life.
According to [https://www.technologyreview.com/2023/02/14/1068582/everything-you-need-to-know-about-heat-pumps/ MIT Technology review]:
<blockquote>Heat pumps today can reach 300% to 400% efficiency or even higher, meaning they’re putting out three to four times as much energy in the form of heat as they’re using in electricity. For a space heater, the theoretical maximum would be 100% efficiency, and the best models today reach around 95% efficiency.</blockquote>

See also [[2790: Heat Pump]].
|-
|{{w|Laser eye surgery}}||Surgical techniques using lasers for precision cutting in the eyeball.||data-sort-value="-60%"|-60%||data-sort-value="+90%"|90%||In the popular imagination, lasers are often thought of as something used for destroying their target. In fact, laser pointers commonly include warnings about how and when they should be used. Firing them into people's eyes, then, does not sound like a great idea.{{Citation needed}} However. this technology has substantially improved the eyesight of millions of people worldwide by allowing the treatment of eye problems otherwise only corrected by lenses or entirely untreatable. Randall has previously commented on laser eye surgery, amongst other ideas both good and bad, in [[1681: Laser Products]].
|-
|{{w|Fecal transplant}}s||Transfer of portions of the {{w|Gut microbiota|gut microbiome}} of a healthy person to the sterilized gut of an ill person.||data-sort-value="-110%"|-100%||data-sort-value="+95%"|95%||The gut microbiome is a collection of organisms that lives in our guts. It can influence our health. It is responsible for the last stages of digesting our food. It can also produce neurotransmitters that are carried by blood to our brain influencing our behavior, and play a role in disease immunity, among other systemic effects that are still not well understood. A healthy microbiome can be destroyed by bad eating habits, unhealthy lifestyles, infections or the use of antibiotics. Sometimes it may be beneficial to completely sterilize the gut and then take a sample of a healthy biome from another person. A sample is enough, as the organisms will multiply. As long as the patient eats correctly, the microbiome after transplant should develop correctly.

It sounds bad because we tend to think of our feces as something gross, to be discarded, and other people's bacteria as infectious. It is called fecal transplant as our feces contain about 50% of gut bacteria, but nowadays the sample usually takes the form of a coated pill that is applied rectally.
|-
|}

==Transcript==
:[Two axes with double arrows cross each other in the middle. At the end of each arrow, there are labels. Scattered over the chart are 28 entries. Below these entries are given for each of the four quadrants, plus three that are on the Y-axis. For each quadrant the entries are listed in reading order, top to bottom left to right.]

:[X axis from left to right:]
:Sounds like a good idea
:Sounds like a bad idea

:[Y axis from top to bottom:]
:Actually a bad idea
:Actually a good idea

:[Top left quadrant (sounds like a good idea, actually a bad idea):]
:Leaded gasoline
:Asbestos
:Always saying what you think
:Solar cars
:Heelies
:Prequels
:Transitions® lenses

:[Top middle (actually a bad idea):]
:Extension cords with prongs on both ends

:[Top right quadrant (sounds like a bad idea, actually a bad idea):]
:Bloodletting
:Fake prank fire extinguishers
:Stair kayaking
:Replying to spammers
:Cutting pizza in squares
:Project Orion

:[Center (neutral):]
:Soup

:[Bottom left quadrant (sounds like a good idea, actually a good idea):]
:Combo washer dryers
:Cutting sandwiches diagonally
:Toasting sandwiches
:Sliced bread
:Pizza
:Wheels on luggage
:Heat pumps

:[Bottom middle (actually a good idea):]
:Eating citrus fruit while at sea

:[Bottom right quadrant (sounds like a bad idea, actually a good idea):]
:Diverging diamond interchanges
:Crumple zones
:Putting mold on infections
:Laser eye surgery
:Fecal transplants

==Trivia==
*A much leaner version of this comic appeared in the first [[What If? (book) | "What If?" book]], chapter "Weird (and Worrying) Questions from the What If? Inbox, #9".

{{comic discussion}}

[[Category:Charts]]
[[Category:Scatter plots]]
[[Category:Rankings]]
[[Category:Food]]

Talk:2956: Number Line Branch

2024-07-21T07:52:44Z

162.158.154.206:

Is it significant that the branch point is close to the value of π? [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 20:28, 8 July 2024 (UTC)
:I was thinking the same thing, but decided it was probably nothing worth mentioning - probably just an arbitrary starting point. *Possibly* referencing the strange appearance of π but I doubt it. Anything can be significant if you believe hard enough, anyway.--[[Special:Contributions/162.158.158.60|162.158.158.60]] 20:30, 8 July 2024 (UTC)
: Keep in mind π isn't special. Most real numbers are like π. The rational numbers, and the roots of polynomials with rational coefficients (algebraic completion), are the aberration. --[[Special:Contributions/172.71.160.71|172.71.160.71]] 07:25, 10 July 2024 (UTC)

How does adding a new branch to a railway line reduce congestion? Isn't this more like a highway? [[Special:Contributions/141.101.105.47|141.101.105.47]] 23:30, 8 July 2024 (UTC)
:Read about the 2nd avenue subway. [[Special:Contributions/172.70.111.168|172.70.111.168]] 02:22, 9 July 2024 (UTC)

What is "thrembo"? [[User:AndroidTheLucario|Your favorite aura doggo]] ([[User talk:AndroidTheLucario|talk]]) 04:12, 9 July 2024 (UTC)
: I think the whole section can be removed. The point is to explain the comic, not to describe what is seen (unless it's relevant for the explanation, which, so far, seems not be the case). "Various symbols" should cover it. [[User:Elektrizikekswerk|Elektrizikekswerk]] ([[User talk:Elektrizikekswerk|talk]]) 06:35, 9 July 2024 (UTC)

The symbols seem well chosen TBH, I can totally see how they substitute for 4, 5, 6, 7, 8 [[Special:Contributions/162.158.146.32|162.158.146.32]] 14:42, 9 July 2024 (UTC)
:Except that, according to the title text, they should be 4, 8, 16, 32, 64. [[Special:Contributions/172.71.242.159|172.71.242.159]] 15:59, 9 July 2024 (UTC)
::I think that the express train travels on the regular number line, so I think the second branch parallels the regular number line. Thus, 4, 5, 6, 7, 8. [[User:Sarah the Pie(yes, the food)|Sarah the Pie(yes, the food)]] ([[User talk:Sarah the Pie(yes, the food)|talk]]) 02:11, 10 July 2024 (UTC)

Mathematicians been there, done that: https://en.wikipedia.org/wiki/Non-standard_model_of_arithmetic
Although a nonstandard model of the integers can't branch by Peano axioms. [[Special:Contributions/172.71.160.71|172.71.160.71]] 15:08, 9 July 2024 (UTC)
:Hold my beer! [Prompts Claude 3.5 Sonnet to create a non-standard model of arithmetic.]
::"Here is a non-standard model of arithmetic consistent with the Peano postulates:
::Axioms:
::
::∃0, ω : 0 ≠ ω
::∀x : S(x) = x + 1 if x ∈ ℕ; S(ω) = ω
::
::Theorems:
::T1. ∀n ∈ ℕ : n < ω
::T2. ∀n ∈ ℕ : n + ω = ω
::T3. ω + ω = ω
::
::Lemma:
::L1. ∀n ∈ ℕ : S(n) ≠ ω
::"Induction" Principle:
::For any property P, if P(0) ∧ P(ω) ∧ (∀x : P(x) → P(S(x))), then ∀x : P(x)
::
::Conclusions:
::C1. This model "satisfies" Peano axioms while introducing a non-standard element.
::C2. Arithmetic with ω leads to paradoxical results.
::C3. Use of this model may violate conservation of sanity."

:Oh, no! .... Tentacled one sleeps. Ph'nglui mglw'nafh Cthulhu. Accept this new soul. [[Special:Contributions/172.70.210.103|172.70.210.103]] 03:24, 10 July 2024 (UTC)
:::That is just the ''[later edit:'' positive'']'' integers plus infinity, it should place you in the thrall of Asmodeus, not Cthulhu. [[Special:Contributions/108.162.245.42|108.162.245.42]]
::::The Russell-Riemann-Cantor diagonalization applies to integers with infinity, mapping each integer to a tentacle on an Eldritch manifold. [[Special:Contributions/172.70.210.53|172.70.210.53]] 03:59, 10 July 2024 (UTC)

Personally I would have branched off between 9 and 10, and had single character symbols for 10, 11, 12, 13, 14, and 15 so that you could do base 16 without having to use letters. Randell just lacks vision. [[User:Andyd273|Andyd273]] ([[User talk:Andyd273|talk]]) 15:12, 9 July 2024 (UTC)
:Letters are single character symbols! I think he should extend the number line with all the letters, getting to 36 (z) before needing any new symbols[[User:PotatoGod|PotatoGod]] ([[User talk:PotatoGod|talk]]) 21:46, 9 July 2024 (UTC)

In my eyes they all seem like geometry or geometry-related symbols. A square, sideways pi, phi (the golden ratio), a spiral, and a triangle. That should probably be noted somewhere.--[[User:Rerere284|Rerere284]] ([[User talk:Rerere284|talk]]) 18:23, 10 July 2024 (UTC)
: I was thinking that the first symbol looks like a square too, so what is this stuff about a Brahmi letter instead of a square? How do we get that complicated with a square? [[User:Ianrbibtitlht|Ianrbibtitlht]] ([[User talk:Ianrbibtitlht|talk]]) 18:57, 10 July 2024 (UTC)

assuming particular mappings of the depicted symbols to phonemes, and saying "Putting these 5 phonemes together gives a word that sounds a bit like 'bisect,'" is absolutely a stretch and should be removed. --[[Special:Contributions/162.158.159.208|162.158.159.208]] 22:20, 10 July 2024

I'm rather surprised that these mathematicians have decided to subdivide each integer by 8, instead of by 10, like good metricists.[[Special:Contributions/172.70.86.132|172.70.86.132]] 08:13, 11 July 2024 (UTC)

It looks to me that the split happens just beyond 3, probably at around 3.14156... [[User:Xplora1a|Xplora1a]] ([[User talk:Xplora1a|talk]]) 13:09, 11 July 2024 (UTC)

The new branch comes up between 3 and 4, which may reference The Secret Number, a sci-fi novel in which a mathematician find a number between 3 and 4. [[User:799571388|799571388]] ([[User talk:799571388|talk]]) 07:41, 16 July 2024 (UTC)

Not even a mention of the line with two origins. Who are you people?[[Special:Contributions/162.158.154.206|162.158.154.206]] 07:52, 21 July 2024 (UTC)

Talk:2530: Clinical Trials

2021-10-20T10:38:22Z

162.158.154.206:

Is this comic in reaction to some specific recent event? It seems like it might be related to vaccine trials, given the pandemic the world has been dealing with for the last 2 years... if so, it then seems to be a condemnation... am I reading too much into this?
[[User:Ericfromabeno|Ericfromabeno]] ([[User talk:Ericfromabeno|talk]]) 21:49, 18 October 2021 (UTC)
:That's exactly how I understood it as well. Maybe that wasn't Randall's intent, but it does seem to convey a skeptical tone about the untested vaccines and their related mandates? [[Special:Contributions/127.0.0.1|127.0.0.0]] 18:56, 19 October 2021 (UTC)

I would say this in relation to the mutiple treatments for Covid19 some of which have great clinical evaluation, others less so. I'll make a first draft [[User:Kev|Kev]] ([[User talk:Kev|talk]]) 21:53, 18 October 2021 (UTC)
:On this website there are far too many people who think everything is about Covid19. --[[Special:Contributions/162.158.88.219|162.158.88.219]] 06:30, 19 October 2021 (UTC)
::It comes to mind after a year full of iterations of the "3-step clinical trial procedure" shown in the comic. See e.g. https://en.wikipedia.org/wiki/List_of_unproven_methods_against_COVID-19

Note that a proper clinical trial does not "prove" its treatment to be effective, but it actually should do its damnedest to show that any observed (net) benefits are down to simple statistical fluke, but then fail, leaving the positive result 'proven'. And obviously extract every possible risk factor in the process. (Thalidomide fell down badly on this, many years ago, partly because of the numbers involved and the fact that susceptible mothers were often taking a cocktail of multiple 'remedies' over much of the nine months, which made the reality slow to be teased out. But the lessons learnt mean that authorising ''anything'' for pregnant women are tortuous, and testing on (non-pregnant) women in general is hampered by having to account for menstral cycles, so we end up with far too many man-tested drugs that say "not for use in pregnancy" just to keep far to the safe-side, plus still far more unknown levels of efficacy/etc in the 'generic' female body than we should have. But it's being addressed. Onward, ever onward!) [[Special:Contributions/162.158.159.49|162.158.159.49]] 23:14, 18 October 2021 (UTC)

The way I understood the title text was that the "change" was the one written in red, that is "now we have to do clinical trials". The title text's joke is thus that, because before that change clinical trials weren't part of the procedure ("standard of care"), you don't have to test the idea of testing ideas. Closely related to that "joke" is https://existentialcomics.com/comic/404 (but seriously this isn't a simple problem). [[Special:Contributions/108.162.229.101|108.162.229.101]] 01:21, 19 October 2021 (UTC)

Shouldn't Test if it works be step 2? Have idea, see if it works, impliment? [[Special:Contributions/172.68.129.137|172.68.129.137]] 01:52, 19 October 2021 (UTC)
:No. Steps 1 and 2 both include elements of testing and exploration; you need to perform experiments to come up with a good idea and convince -yourselves- that it is, in fact, good, and then you likely need to perform or at least show more tests to convince others that it is, in fact a good idea. But the addition of clinical trials added a further "and then you need to double triple check that your idea actually works rather than that it seemed to work in your initial experiments" step to (try to) avoid bad side effects and false correlation. [[User:Mneme|Mneme]] ([[User talk:Mneme|talk]]) 02:40, 19 October 2021 (UTC)
:I'm of the opinion that it was part of the joke... since it does seem to follow the actual behavioral pattern of "do thing, promote thing, [justify thing], propagate thing"... which makes this thread of conversation both topical and meta (kudos to Randall if ''this'' result was intended)[[Special:Contributions/162.158.107.4|162.158.107.4]] 21:14, 19 October 2021 (UTC)

Mention of "anti-worming treatments" in the explanation. This is misleading, and gives the impression that drugs can only have a single function. It's like talking about the use of "headache medicine" for preventing heart attacks. If you want to refer to a specific medicine, do so by name but make damn sure that your claims about that medicine are accurate [[User:Mneme|Mneme]] ([[User talk:Mneme|talk]]) 04:36, 19 October 2021 (UTC)

While the awareness of clinical trials is of course more relevant because of COVID, I don't think this is intended to be topical. The title is very straightforwards-- "the invention of clinical trials" and is almost joke-less (basically just the format). The real joke is in the title text, where it's pointed out that because the "standard of care" before the invention of clinical trials was not to do clinical trials, we didn't need to go through this step to start doing them; just convince people it was a good idea. 02:40, 19 October 2021 (UTC)
: I think it's *extremely* topical, with the relatively recent debunking of ivermectin as (yet another) substance that has been widely claimed, distributed, and mis-used as a supposed COVID preventative/cure. [[User:BunsenH|BunsenH]] ([[User talk:BunsenH|talk]]) 03:49, 19 October 2021 (UTC)
:: If you like, it is topical by -context-, but not by content. Which is an interesting (but important) line to draw. [[User:Mneme|Mneme]] ([[User talk:Mneme|talk]]) 04:31, 19 October 2021 (UTC)

A recent editor pulled out my comment about how there isn't a joke, but I'd argue that that's necessary in some form. One of the reasons people go to Explain XKCD is that they're going "wait, did I miss a joke?" So explaining that as far as the community is concerned the main text is in-earnest education rathar than a missed joke does have an important purpose. [[User:Mneme|Mneme]] ([[User talk:Mneme|talk]]) 04:37, 19 October 2021 (UTC)

This list looks like the difference between philosophy, particularly ancient Greek and Indian philosophy (probably others, but I do not know them as well), and science. The philosophical ideas were adopted based on who was able to convince more people that they had a better idea. When the scientific revolution rolled around in the 15th and 16th century in Europe, many of these ancient ideas were actually tested and only those that really worked were retained as true. Many well known and well respected ideas that failed testing were finally abandoned. That sure sounds like the elements of this list. [[User:Nutster|Nutster]] ([[User talk:Nutster|talk]]) 07:11, 19 October 2021 (UTC)

The Covid-19 paragraph seems a bit misleading. Arguments advanced in favour of vaccine skepticism have mostly been not so much to do with treatments being used before clinical trials were complete, as with clinical trials being brought forward to accelerate the process, which has been misinterpreted as them being 'rushed'. [[Special:Contributions/162.158.154.206|162.158.154.206]] 10:38, 20 October 2021 (UTC)

Talk:2529: Unsolved Math Problems

2021-10-20T10:25:38Z

162.158.154.206:

Does anyone have any clue whether the writing on the board in the weirdly abstract panel means anything? Maybe add an explanation about it?[[Special:Contributions/162.158.227.91|162.158.227.91]] 13:23, 17 October 2021 (UTC)

Center panel possibly related to "The drunkards walk" and theories on randomised motion.
https://www.quantamagazine.org/random-walk-puzzle-solution-20160907/
More references https://mathworld.wolfram.com/RandomWalk.html

Someone's gotta point out that "walking randomly on a grid, never visiting the same square twice" would rapidly trap you in a corner (even the example has a 50/50 chance of that happening on the next move) [[Special:Contributions/172.70.130.125|172.70.130.125]] 04:29, 16 October 2021 (UTC)

Not if it's an infinite grid.

I think there's two different ways to interpret the question - as a uniform random element of the set of all non-self-intersection NxK length paths, in which case it's fine, or as a path defined by a random walk in which moves onto your own path are not allowed, which doesn't seem well defined, since you might end up in a situation where you are surrounded by your own path and cannot continue for all NxK steps.

An early example of a cursed problem is the Cantor Function. https://en.wikipedia.org/wiki/Cantor_function

I admire whoever wrote the description of the curve in the "cursed" panel. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 05:36, 16 October 2021 (UTC)

"Algebreic" is a misspelling of "algebraic". Could Randall really have made this mistake, or is it another malamanteau? What does "breic" come from? [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 06:10, 16 October 2021 (UTC)

I wonder if Randall was actually referring to that quote about "Into the Woods", or he just thought "Sondheim calculus" sounded cool and it was a total coincidence. I found it when I googled "sondheim calculus" to make sure it wasn't a real thing. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 06:29, 16 October 2021 (UTC)

In panel 2, what would 'k' be? [[Special:Contributions/172.69.35.108|172.69.35.108]] 08:00, 16 October 2021 (UTC)

'k' would represent the number of marbles placed on the ground. [[Special:Contributions/162.158.88.127|162.158.88.127]] 08:09, 16 October 2021 (UTC)
:Though probably correct, I think the implied state is that an integer multiple (k) of N steps is made (s=N*k), with that number of marbles dropped, not s=(N*k)+c steps (for N>c) which would have the same result (uselessly) for all values of s where c ranges 0..N-1. It just introduces inflections into the graph (with s as an axis) that needn't be there (with just a k-based one). Or, in other words, selectively poll all s-values that are exactly divisible by N, and forget all the rest. (That divisor is k, and hence k is the number of marbles. Or perhaps k+1 if you leave one on the starting spot too.) [[Special:Contributions/162.158.159.25|162.158.159.25]] 21:59, 16 October 2021 (UTC)

To me, the cursed curve looks a bit like a crosier https://commons.wikimedia.org/wiki/File:Crosiere_of_arcbishop_Heinrich_of_Finstingen.jpg

--> I had the same impression and added it. --[[Special:Contributions/162.158.94.219|162.158.94.219]] 11:40, 16 October 2021 (UTC)

No explanation of the "Euler Field Manifold Hypergroup (Isomorphic to a)..." part?

The cursed curve looks almost like someone took a graph of the Binet formula in the complex plane, stretched it out a bit, and rotated it onto the i axis.
: This was my first thought too when I saw it. [[Special:Contributions/172.69.34.87|172.69.34.87]] 17:16, 16 October 2021 (UTC)
: It looks like Vulcan script to me. [[User:LtPowers|LtPowers]] ([[User talk:LtPowers|talk]]) 13:51, 16 October 2021 (UTC)
: That's what it looks like to me too; recognized it from that Numberphile video on Fibonacci numbers in the complex plane [[Special:Contributions/108.162.245.245|108.162.245.245]] 07:36, 17 October 2021 (UTC)
: It looks to me like someone has raised a dark spirit, which is about to manifest from a column of black smoke. [[Special:Contributions/162.158.154.206|162.158.154.206]] 10:25, 20 October 2021 (UTC)

Could the cursed curve be a reference to the logistic map?

Can someone produce a high resolution image of the Cursed Curve? It needs to be on a T-shirt [[User:Avimimus|Avimimus]] ([[User talk:Avimimus|talk]]) 21:39, 16 October 2021 (UTC)

Is someone going to mention the title text?

I swear I've seen that third plot, I thought it was in XKCD, but a quick run through tagged entries didn't find anything... unfortunately I consume a lot of math media so I can't place it. It's bugging me so I hope this note will serve as encourgement to someone that DOES remember [[Special:Contributions/162.158.106.221|162.158.106.221]] 21:29, 16 October 2021 (UTC)
:I'm sure I've seen components of the cursed-curve, not sure if they fit together like that, easily, though. The differentiation of dy/dt (which is odd in itself) of the first (lower) bit looks discontinuous, followed by a chaotic oscilation (may just be the culmination of the less frenetic chaos that created the first set of x=f(y) - again, an unusual way round) that then settles into a pattern where ''regardless'' of the 'prime axis', you have multiple real roots on the other, towards some great-attractor value.
: In more standard x/y (or y=f'(x)?) notation, it is clear that there are multiple real roots for various values of x within a range, and possible none at all beyond that (or it's a plotting error insofar as x tends to ±infinity it has a very narrow range of y that is never sampled properly, but should connect to that pulse 'randomness'). If it's a plot of real vs imaginary components of a complex function to a different continuous value, I suspect someone is playing silly-buggers with multiple (perhaps nested?) trigonometric functions, polynomials and variable-shifted powers. But it's nearly thirty years since I did mathematics at the level needed to disentangle this neatly (back when Mandelbrots and Julias were still a staple wall-poster for any student not more into the likes of Iron Maiden skull-motifs or <insert your favourite classic film here>, and even then it might be) so don't ask me where to start. [[Special:Contributions/162.158.89.140|162.158.89.140]] 16:48, 17 October 2021 (UTC)

To me the curve in panel three looks like a cursed (ha) mixture of an oscillatory time responses of dynamic systems with either an Nquist plot or simply trajectories of eigenvalues (of a stable system) at the end. Links: https://en.wikipedia.org/wiki/Nyquist_stability_criterion#Nyquist_plot , https://electronicscoach.com/time-response-of-second-order-system.html https://en.wikipedia.org/wiki/Eigenvalues_and_eigenvectors [[User:Domi|Domi]] ([[User talk:Domi|talk]])Domi

Are there any examples of "cursed" math problems? I've seen "weirdly abstract" and "weirdly concrete" ones, but not "cursed" ones. [[Special:Contributions/162.158.63.117|162.158.63.117]] 01:03, 17 October 2021 (UTC)

The symbol in the third panel looks like an unalome, which is not a mathematical symbol but a Buddhist or mystical one https://en.wikipedia.org/wiki/Yantra_tattooing#Types_and_designs

There is at least one paper on arxiv defining quasimonoid, 1401.7748. It's from 2014 so it existed long before the comic. --[[Special:Contributions/162.158.88.253|162.158.88.253]] 14:04, 17 October 2021 (UTC)

Links, '''please'''! Not all of us are mathematicians. If you mention something that you think the cursed curve might represent, please provide a link to something describing that something so the rest of us can read it and attempt to learn more. [[User:Shamino|Shamino]] ([[User talk:Shamino|talk]]) 17:44, 17 October 2021 (UTC)

That cursed squiggle sure looks like the sort of thing that used to flow from {{w|Saul Steinberg}}'s pen, as seen in the pages of the New Yorker back in the 60s. The most relevant example I can find right now is from 1965: https://fineartamerica.com/featured/new-yorker-february-20th-1965-saul-steinberg.html [[Special:Contributions/162.158.255.177|162.158.255.177]] 03:38, 18 October 2021 (UTC)

So, is the middle one an actual unsolved problem? --[[Special:Contributions/162.158.91.236|162.158.91.236]] 16:07, 18 October 2021 (UTC)

In this comic ponytail is obviously not Dr. Adams. (Discussion came up two comics ago.) --[[Special:Contributions/162.158.88.115|162.158.88.115]] 21:42, 18 October 2021 (UTC)

Is Panel #2 a real unsolved problem? It reads like one.

Adding to the first comment - should we include an explanation of the formula in the first panel as well? The denominator means "is an element of aleph-5, the fifth [https://en.wikipedia.org/wiki/Aleph_number infinite cardinal number]". The numerator is less clear; a dot over a variable usually indicates a derivative, but I haven't seen a dot over a set. Raising R (set of real numbers) to the power of Z (set of integers) refers to the set of all functions from the integers to the reals. I don't recognize the diamond with a line through the bottom or the two arrows.

Shout-out to whoever wrote the incomplete tag. [[Special:Contributions/162.158.74.172|162.158.74.172]] 20:21, 19 October 2021 (UTC)

Is there a reason why the article uses "millennium" (correct) and "millenium" (incorrrect)?