explain xkcd - User contributions [en]

2501: Average Familiarity

2021-08-12T13:08:19Z

141.101.99.220: /* Explanation */ Additional trivia. In leiu of a Trivia section. (Not worth it for this one snippet, I thought.)

{{comic
| number = 2501
| date = August 11, 2021
| title = Average Familiarity
| image = average familiarity.png
| titletext = "How could anyone consider themselves a well-rounded adult without a basic understanding of silicate geochemistry? Silicates are everywhere! It's hard to throw a rock without throwing one!"
| imagesize =
}}

==Explanation==
{{incomplete|Created by A SILICATE (DON'T WE ALL KNOW THE FORMULA?). Do NOT delete this tag too soon.}}

This comic claims that scientists vastly overestimate how familiar other people are with their own field of study. As an example, Randall shows a pair of {{w|geochemistry|geochemists}} specializing in {{w|silicate}} chemistry. The scientists are under the impression other people at least know the chemical makeup of {{w|olivine}}, some {{w|feldspar}}s and {{w|quartz}}. In truth, the average person can't be expected to know the chemical makeup of ''any'' arbitrarily-chosen substance reliably (or any material at all, if that average person's job and hobby do not involve chemistry — aside from the few that made their way into {{w|common knowledge}}, like H2O for water or CO2 for carbonic gas), and may not even know the definition of "feldspar" beyond "a rock", if at all.

It even goes so far as to initially gloss over the 'everyday' knowledge of quartz. Perhaps like a gardener forgetting to mention the lawn he maintains (along with the 'actual' plants in the borders or vegetable patches), there seemed no need to mention such a trivial inclusion in the set of things ''everybody'' knows'... until prompted by the slightly-less-overestimating partner in the conversation. Quartz is a basic silicon oxide (SiO2) that ''can'' be found as distinct large-scale crystals (probably obvious to the layman, as an ice-cube is in a drink) but also features as a hard-wearing micro-constituent of many rocks, even as erosion and other processes act upon them. At a certain high level of weathering - hazily defined as between gravels and silts - sand is overwhelmingly the ultimate residual silicon-dioxide grains in most cases (the main exception to this being coral sands, which are calcium carbonates) though with varying internal linkages as SiO4 'units' (sharing oxygen atoms) and other residual constituents dictating the general colour, feel and other physical qualities as you enjoy your day at the beach.

The title text plays on the phrase "you can't throw a rock without hitting one," a common hyperbole about how common something is. Indeed, {{w|Silicate mineral|silicate}} rocks are extremely common on Earth — not only would a rock thrown in a random direction stand a decent chance of striking a silicate mineral rock (assuming the thrower is out in a field instead of indoors [or is indoors with brick and tile]) but the randomly-selected rock being ''thrown'' also has a very high chance of being a silicate mineral rock. You would probably have to be standing upon a desert island to be most unable to discover a silicate substance to throw/hit, although dig a little and you may yet find the atoll is founded upon an ancient volcanic plug that is primarily silicates. Otherwise, go to your nearest chalk downland (carbonaceous), but know that your search is over if you see any embedded flint (silicaceous). As a whole, the Earth's crust is about 30% silicon, second in rank only to the oxygen with which it and other elements are commonly bound.

==Transcript==
:[Ponytail and Cueball are standing and talking. Ponytail has her palm raised.]
:Ponytail: Silicate chemistry is second nature to us geochemists, so its easy to forget that the average person probably only knows the formulas for olivine and one or two feldspars.
:Cueball: And quartz, of course.
:Ponytail: Of course.

:[Caption below the panel]
:Even when they're trying to compensate for it, experts in anything wildly overestimate the average person's familiarity with their field.

{{comic discussion}}
[[Category:Geology]]

2501: Average Familiarity

2021-08-12T08:55:37Z

141.101.99.220: s/average Joe/average person/ to match comic's neutral language rather than not male US centric

Talk:1317: Theft

2014-01-16T01:48:10Z

141.101.99.220:

This comic seems to be about the idea that true identity theft would require the thief to take on the identity perfectly. The thief in the comic is Randall Munroe making fun of himself and how he is often existential and is excited about space... 1st post--[[Special:Contributions/173.245.55.78|173.245.55.78]] 05:19, 15 January 2014 (UTC)

Maybe it's a shared account, so it really is Megan's own existentialism & Randall's love of space -- a true crisis!
[[Special:Contributions/108.162.216.57|108.162.216.57]] 15:10, 15 January 2014 (UTC)

Is it worth mentioning the contextual element where this comic correlates with the relase of news of a rash of identity theft during the last quarter of 2013?[[Special:Contributions/199.27.128.137|199.27.128.137]] 00:54, 16 January 2014 (UTC)

The title text is a reference to a Greg Egan short story from the collection Axiomatic called Learning to be Me. [[Special:Contributions/141.101.99.220|141.101.99.220]] 01:48, 16 January 2014 (UTC)