explain xkcd - User contributions [en]

2960: Organ Meanings

2024-07-18T16:36:12Z

Maparent: /* Explanation */

{{comic
| number = 2960
| date = July 17, 2024
| title = Organ Meanings
| image = organ_meanings_2x.png
| imagesize = 407x346px
| noexpand = true
| titletext = IMO the thymus is one of the coolest organs and we should really use it in metaphors more.
}}

==Explanation==
{{incomplete|Created by a BOT'S PINEAL GLAND - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
This is a graph by [[Randall]] ranking how well he understands the function of certain human organs, compared to how much he understands {{w|metaphor}}s using them. 

A number of organs (and other body parts) are used in common vernacular for metaphorical meaning. The English language is full of sayings like "she had a lot of heart", "go with your gut", and "he hasn't got the stomach for it". One might expect understanding an organ's role and its use in metaphor to be strongly correlated, since the metaphors generally work by drawing a parallel to biological function. However, since our understanding of biological functions has evolved dramatically over time, and metaphorical language does not always keep up, the correspondence is often much looser. To complicate matters, many such anatomical metaphors vary from culture to culture, even though the biological functions remain largely consistent.{{Citation needed}}

The {{w|pineal gland}}, located in the center of the brain, was described as the “Seat of the Soul” by the dualist {{w|René Descartes}} in the 17th century. If this was what it was, the metaphors that might be derived from it would be pretty explicit. It was only in the mid-20th century that its real neuroendocrine (hormone-producing) biological role was grasped. Thus, the real meaning of the metaphor "the pineal gland of something" is uncertain, as is its actual function for the layman. It was also described as a "third eye", as its regulation of the circadian rhythm used to be linked to light perception in the organ, and still is in Tuataras.

The {{w|thymus}}, highlighted in the title text, plays an important role in the immune system. It is not commonly used in metaphors,{{Citation needed}} but is perhaps ripe for use in ones describing such things as resilience, indomitability, and adaptability to changing circumstance, were more people to know what it was.

{| class="wikitable" style="margin:auto"
|-
! Organ !! Biological understanding !! Metaphor understanding !! Biological function !! Metaphor meaning(s)!!Comments
|-
| {{w|Appendix_(anatomy)|Appendix}} || 3% || 85% || Maintaining gut flora, introducing pathogens to the immune system || Uselessness || The appendix was long assumed to be vestigial with no useful function, and it can be removed with minimal consequences. Modern research has show that it retains utility as reservoir for useful micro-organisms.
|-
| {{w|Nerves}} || 40% || 90% || Sensing stimuli, and controlling muscles and organs || Courage; lack of courage; unsettledness; arrogance; (emotional) feeling
|-
| {{w|Spine}} || 50% || 80% || Holding other bones up, protecting the spinal cord || Courage; resoluteness; structural integrity; centrality
|-
| {{w|Heart}} || 80% || 90% || Circulation of blood || Emotion; feeling; sympathy; love; courage; resilience; core; essence; the vulnerable self || The function of the heart is (relatively) easy to understand, since it is, in essence, a circulatory pump. But it's long been culturally associated with emotion and resolve.
|-
| {{w|Bones}} || 75% || 80% || Holding the skin and muscles up, and protection of underlying organs || Basic/underlying structure; something hidden; core; essence; an issue of debate
|-
| {{w|Stomach}} || 70% || 65% || Repository for cake and other, less important, foods || Ability to tolerate unpleasant circumstances; motivation || The stomach's primary function is as part of the digestive system, but it's often one of the first organs impacted by illness or disgust, which has made a strong stomach a metaphor for constitution and resolve.
|-
| {{w|Liver}} || 10% || 48% || Processing alcohol and other less important metabolic functions like toxin inactivation, decomposition/production of amino acids and lipids, etc. || Courage or lack thereof (e.g. lily livered)
|-
| {{w|Lungs}} || 60% || 52% || Oxygenation of blood; exhalation of carbon dioxide || Loudness (e.g. of singing); purification
|-
| {{w|Spleen}} || 22% || 34% || Storing extra blood, filtering blood for damaged cells and pathogens || Anger; viciousness
|-
| {{w|Thymus}} || 10% || 13% || Training immune cells (T-Cells) ||
|-
| {{w|Kidneys}} || 47% || 19% || Filtering blood for metabolic wastes and excess minerals ||
|-
| {{w|Pineal gland}} || 2% || 2% || Produces melatonin ||
|-
| {{w|Tongue}} || 70% || 5% || Taste; chewing; speaking || Speaking/Language; unidentified speakers (particularly in relation to gossip/secrets); something long and extended
|}

==Transcript==
:[A graph is shown with X and Y-axis without arrow or ticks. To the left of the Y-axis and below the X-axis there are labels with an arrow pointing up from the top of the Y-axis label and an arrow pointing right above the X-axis label, just beneath the x-axis.]
:Y-axis: How well I understand what it means when used in metaphors
:X-axis: How well I understand its actual biological function

:[On the graph is a scatter plot with 13 labels. Each label is written inside a line that goes just around the words. There are most in the top right corner, but they are spread all over the graph. Here in approximate reading order from top left with indicating of where on the graph the words are located:]
:[Top left:]
:Appendix
:[Top middle:]
:Nerves
:Spine
:[Top right:]
:Heart
:Bones
:Stomach
:[Center left:]
:Liver
:Spleen
:[Center right:]
:Lungs
:[Bottom left:]
:Thymus
:Pineal gland
:[Bottom middle:]
:Kidneys
:[Bottom right:]
:Tongue

{{comic discussion}}

[[Category:Scatter plots]]
[[Category:Rankings]]
[[Category:Biology]]
[[Category:Language]]

2911: Greenland Size

2024-03-26T10:11:33Z

Maparent: typo

{{comic
| number = 2911
| date = March 25, 2024
| title = Greenland Size
| image = greenland_size_2x.png
| imagesize = 262x304px
| noexpand = true
| titletext = The Mercator projection drastically distorts the size of almost every area of land except a small ring around the North and South Poles.
}}

==Explanation==
{{incomplete|Created by a GREEN LAND FOR ANTS - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
Because the Earth is curved, all flat maps have some distortion. (A common comparison is flattening an orange peel, which cannot be done without tearing and wrinkling it.) Different {{w|map projection}}s can distort different {{w|Map projection#Metric properties of maps|metric properties}}, such as distances, areas, and angles, while leaving others intact. It can be desirable to preserve different metrics in different applications.

The {{w|Mercator projection}}, depicted in the comic, prioritizes depicting correct angles. This allows for easy course planning at sea, and makes shapes fairly accurate. In exchange, Mercator is often criticized for distorting size: distances near the poles look larger than the same distance near the {{w|equator}}. A common complaint is that {{w|Greenland}} appears as big on the map as {{w|Africa}}, when Africa actually has 14 times as much area as Greenland. When these size distortions are presented out of context, they can create bias and misconceptions about different places.

[[Cueball]]'s dialogue leads the reader to expect this complaint. However, instead of comparing ''relative'' sizes of two landmasses within the map, [[Cueball]] compares the ''absolute'' sizes of the depiction of Greenland and the actual Greenland. On a typical world map, Greenland might be centimeters or inches across. Judging from the human characters, the mapped Greenland in this comic might be 10 cm across. In real life, Greenland is about 650 miles or 1,050 km across from east to west ([//britannica.com/place/Greenland source]). Cueball deems this difference misleading, presenting it as a failure of this specific map or projection.

Of course, this is absurd. The purpose of any map is to present information much more compactly so that it is easy to read and interpret. Any actual-size world map would have to be the size of the Earth's surface, in which case it would have few uses. In addition, if a map includes a {{w|Scale (map)|scale}}, it is easy to calculate{{Citation needed}} the actual size of the places depicted.

The title text is about the fact that a horizontal line on a worldwide Mercator projection corresponds to a line of latitude. Most lines of latitude are thousands of miles (kilometers) long, but they become smaller and smaller approaching the poles, and in fact there ''is'' a line of latitude in a small-diameter circle around each pole whose length would equal the width of the map that Cueball is looking at. If Cueball's map were 1 m wide, then this line of latitude would be at 89.999998568° N or S - that is, the line of latitude there would be one circle for each of the poles with a circumference of 1 m.

A map at a scale of 1:1 was discussed in {{w|Lewis Carroll}}'s "{{w|Sylvie and Bruno Concluded}}":

<blockquote>
''"That's another thing we've learned from your Nation," said Mein Herr, "map-making. But we've carried it much further than you. What do you consider the largest map that would be really useful?"'' 
''"About six inches to the mile."'' 
''"Only six inches!" exclaimed Mein Herr. "We very soon got to six yards to the mile. Then we tried a hundred yards to the mile. And then came the grandest idea of all! We actually made a map of the country, on the scale of a mile to the mile!"'' 
''"Have you used it much?" I enquired.'' 
''"It has never been spread out, yet," said Mein Herr: "the farmers objected: they said it would cover the whole country, and shut out the sunlight! So we now use the country itself, as its own map, and I assure you it does nearly as well."''
</blockquote>

The same idea was expanded in {{w|Jorge Luis Borges}}'s "{{w|On Exactitude in Science}}".

Mercator projections have been mentioned previously in [[977: Map Projections]], [[2082: Mercator Projection]], and [[2613: Bad Map Projection: Madagascator]].

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[Cueball and White Hat are looking at a world map on the wall showing a Mercator projection, with Cueball gesturing with his hand towards the map.]
:Cueball: This map is really misleading about the size of Greenland.
:Cueball: It's actually '''''much''''' bigger than that - it's hundreds of miles across.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring White Hat]]
[[Category:Maps]]
[[Category:Geography]]

2911: Greenland Size

2024-03-26T10:10:54Z

Maparent: Added a reference to Borges.

{{comic
| number = 2911
| date = March 25, 2024
| title = Greenland Size
| image = greenland_size_2x.png
| imagesize = 262x304px
| noexpand = true
| titletext = The Mercator projection drastically distorts the size of almost every area of land except a small ring around the North and South Poles.
}}

==Explanation==
{{incomplete|Created by a GREEN LAND FOR ANTS - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
Because the Earth is curved, all flat maps have some distortion. (A common comparison is flattening an orange peel, which cannot be done without tearing and wrinkling it.) Different {{w|map projection}}s can distort different {{w|Map projection#Metric properties of maps|metric properties}}, such as distances, areas, and angles, while leaving others intact. It can be desirable to preserve different metrics in different applications.

The {{w|Mercator projection}}, depicted in the comic, prioritizes depicting correct angles. This allows for easy course planning at sea, and makes shapes fairly accurate. In exchange, Mercator is often criticized for distorting size: distances near the poles look larger than the same distance near the {{w|equator}}. A common complaint is that {{w|Greenland}} appears as big on the map as {{w|Africa}}, when Africa actually has 14 times as much area as Greenland. When these size distortions are presented out of context, they can create bias and misconceptions about different places.

[[Cueball]]'s dialogue leads the reader to expect this complaint. However, instead of comparing ''relative'' sizes of two landmasses within the map, [[Cueball]] compares the ''absolute'' sizes of the depiction of Greenland and the actual Greenland. On a typical world map, Greenland might be centimeters or inches across. Judging from the human characters, the mapped Greenland in this comic might be 10 cm across. In real life, Greenland is about 650 miles or 1,050 km across from east to west ([//britannica.com/place/Greenland source]). Cueball deems this difference misleading, presenting it as a failure of this specific map or projection.

Of course, this is absurd. The purpose of any map is to present information much more compactly so that it is easy to read and interpret. Any actual-size world map would have to be the size of the Earth's surface, in which case it would have few uses. In addition, if a map includes a {{w|Scale (map)|scale}}, it is easy to calculate{{Citation needed}} the actual size of the places depicted.

The title text is about the fact that a horizontal line on a worldwide Mercator projection corresponds to a line of latitude. Most lines of latitude are thousands of miles (kilometers) long, but they become smaller and smaller approaching the poles, and in fact there ''is'' a line of latitude in a small-diameter circle around each pole whose length would equal the width of the map that Cueball is looking at. If Cueball's map were 1 m wide, then this line of latitude would be at 89.999998568° N or S - that is, the line of latitude there would be one circle for each of the poles with a circumference of 1 m.

A map at a scale of 1:1 was discussed in {{w|Lewis Carroll}}'s "{{w|Sylvie and Bruno Concluded}}":

<blockquote>
''"That's another thing we've learned from your Nation," said Mein Herr, "map-making. But we've carried it much further than you. What do you consider the largest map that would be really useful?"'' 
''"About six inches to the mile."'' 
''"Only six inches!" exclaimed Mein Herr. "We very soon got to six yards to the mile. Then we tried a hundred yards to the mile. And then came the grandest idea of all! We actually made a map of the country, on the scale of a mile to the mile!"'' 
''"Have you used it much?" I enquired.'' 
''"It has never been spread out, yet," said Mein Herr: "the farmers objected: they said it would cover the whole country, and shut out the sunlight! So we now use the country itself, as its own map, and I assure you it does nearly as well."''
</blockquote>

The same idea was expanded in {{w|Jorge Luis Borges}}'s "{{w| On Exactitude in Science}}".

Mercator projections have been mentioned previously in [[977: Map Projections]], [[2082: Mercator Projection]], and [[2613: Bad Map Projection: Madagascator]].

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[Cueball and White Hat are looking at a world map on the wall showing a Mercator projection, with Cueball gesturing with his hand towards the map.]
:Cueball: This map is really misleading about the size of Greenland.
:Cueball: It's actually '''''much''''' bigger than that - it's hundreds of miles across.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring White Hat]]
[[Category:Maps]]
[[Category:Geography]]