843: Misconceptions

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"Grandpa, what was it like in the Before time?" "It was hell. People went around saying glass was a slow-flowing liquid. You folks these days don't know how good you have it."
Title text: "Grandpa, what was it like in the Before time?" "It was hell. People went around saying glass was a slow-flowing liquid. You folks these days don't know how good you have it."


The Wikipedia article List of common misconceptions gives a list of commonly-repeated anecdotes that are widely believed to be true, but actually are not.

The teacher, Miss Lenhart, is announcing that since it is the first Tuesday in February, by law and custom the reading of this article is requirement to stem the repetition of these incorrect anecdotes. (Funnily enough the comic was released the first Wednesday in January, which could just as well have been written in the comic).

She continues to make it clear that this is to make the students in general a little less wrong, and the main outcome will be that the guest of any future parties the students ever attend, will not have to listen to them retell these misconceptions and for that these guest will thank those who have decided on this new law in advance.

In the caption below the comic Randall expresses his wishes that he lived in a parallel universe where this rule had been used for many years. So he would not have to listen to all these stories at every party he goes to. Since Randall likes to correct people if they are wrong (see 386: Duty Calls), not having to discuss with those that believe these misconceptions, would make his parties much better.

The title text refers to a specific one of these false stories about glass:

That glass, while seeming solid, is actually an extremely viscous liquid and will flow over time, as is seen on older buildings where the window panes are thicker at the bottom.

In reality, older manufacturing processes did not produce glass panes with as uniform thickness as modern processes, and people tended to install the uneven panes with the thicker side at the bottom for stability. Glass simply does not flow at room temperature; it's more viscous than solid lead by a factor of over a billion. The fact that glass is solid at room temperature was again referenced in a foot note, under the pipe with glass, in 1649: Pipelines.


[Miss Lenhart the teacher is standing in front of a board, looking at a laptop computer she is holding in one hand while elocuting.]
Miss Lenhart: Okay, middle school students, it's the first Tuesday in February.
Miss Lenhart: This means that by law and custom, we must spend the morning reading through the Wikipedia article List of Common Misconceptions, so you can spend the rest of your lives being a little less wrong.
Miss Lenhart: The guests at every party you'll ever attend thank us in advance.
[Caption below the panel:]
I wish I lived in this universe.

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Note: The xkcd forums contain a great discussion of this comic.

When I took Calculus-based Physics in college (2003), my professor taught us that glass was an "extremely viscous fluid." When was glass reclassified as an amorphous solid?
Smperron (talk) Your professor was simply incorrect. Glass never was, and has never been, an "extremely viscous fluid". Molten glass is a "molecular liquid" where the viscosity depends on temperature. 22:14, 13 December 2012 (UTC)
"Extremely viscous fluid" is just another way to describe an amorphous solid (as opposed to the crystallic solid). There is no sharp cut-off between these states. Just at some point it starts feeling solid enough, so it gets called a solid. See the Pitch Drop Experiment [1] for an example (though glass is obviously harder than pitch). 19:21, 16 January 2014 (UTC)

I had a chemistry professor in 2011 tell me that glass flowed, even citing old buildings with thicker glass on the bottom. I tried to argue against it, but I was interrupting a lecture. I discussed it with some students later, though. 00:49, 1 February 2014 (UTC)

If you think you had a problem, try convincing anyone that weather turns into seismic activity and vice versa.

I used Google News BEFORE it was clickbait (talk) 19:53, 24 January 2015 (UTC)

Is there really a law or custom about the first Tuesday in February?, or is that just a misconception? Mountain Hikes (talk) 17:55, 4 January 2016 (UTC)

Note "I wish I lived in this universe" at the bottom. Herobrine (talk) 09:07, 17 April 2018 (UTC)
"Before time"
Why is the "B" in "Before time" capitalized?
If it's a reference to "B.C.", what's the link here?Pacerier (talk) 13:02, 4 March 2016 (UTC)
I believe "the Before time" is a reference to Star Trek (Original) Season 1, Episode 8 "Miri". 22:07, 29 June 2016 (UTC)