The Universe of Discourse


Sun, 14 Apr 2024

Stuff that is and isn't backwards in Australia

I recently wrote about things that are backwards in Australia. I made this controversial claim:

The sun in the Southern Hemisphere moves counterclockwise across the sky over the course of the day, rather than clockwise. Instead of coming up on the left and going down on the right, as it does in the Northern Hemisphere, it comes up on the right and goes down on the left.

Many people found this confusing and I'm not sure our minds met on this. I am going to try to explain and see if I can clear up the puzzles.

“Which way are you facing?” was a frequent question. “If you're facing north, it comes up on the right, not the left.”

(To prevent endless parenthetical “(in the Northern Hemisphere)” qualifications, the rest of this article will describe how things look where I live, in the northern temperate zones. I understand that things will be reversed in the Southern Hemisphere, and quite different near the equator and the poles.)

Here's what I think the sky looks like most of the day on most of the days of the year:

Two similar
hand-drawn diagrams, side by side.  One, labeled ‘SOUTH VIEW’, shows
the sun coming up from a point at the left (east) end of the horizon
labeled ‘sunrise’, passing upward in a circular arc, then down to a
point on the right (west) labeled ‘sunset’.  The other diagram,
labeled ‘NORTH VIEW’, shows the same horizon, but no sun, no arc, and
no sunrise or sunset.

The sun is in the southern sky through the entire autumn, winter, and spring. In summer it is sometimes north of the celestial equator, for up to a couple of hours after sunrise and before sunset, but it is still in the southern sky most of the time. If you are watching the sun's path through the sky, you are looking south, not north, because if you are looking north you do not see the sun, it is behind you.

Some people even tried to argue that if you face north, the sun's path is a counterclockwise circle, rather than a clockwise one. This is risible. Here's my grandfather's old grandfather clock. Notice that the hands go counterclockwise! You study the clock and disagree. They don't go counterclockwise, you say, they go clockwise, just like on every other clock. Aha, but no, I say! If you were standing behind the clock, looking into it with the back door open, then you would clearly see the hands go counterclockwise! Then you kick me in the shin, as I deserve.

Yes, if you were to face away from the sun, its path could be said to be counterclockwise, if you could see it. But that is not how we describe things. If I say that a train passed left to right, you would not normally expect me to add “but it would have been right to left, had I been facing the tracks”.

At least one person said they had imagined the sun rising directly ahead, then passing overhead, and going down in back. Okay, fair enough. You don't say that the train passed left to right if you were standing on the tracks and it ran you down.

Except that the sun does not pass directly overhead. It only does that in the tropics. If this person were really facing the sun as it rose, and stayed facing that way, the sun would go up toward their right side. If it were a train, the train tracks would go in a big curve around their right (south) side, from left to right:

We are
looking down a train platform in Sardinia, with the tracks on our
right.  In the distance the tracks are directly ahead of us, but as
they approach they curve around to our right.

Mixed gauge track (950 and 1435mm) at Sassari station, Sardinia, 1996 by user Afterbrunel, CC BY-SA 3.0 DEED, via Wikimedia Commons. I added the big green arrows.

After the train passed, it would go back the other way, but they wouldn't be able see it, because it would be behind them. If they turned around to watch it go, it would still go left to right:

Mirror image
of the previous picture, as if we were looking the other way down the
same train platform.  Now the tracks begin adjacent to the platform on
our left, and curve off to the right as they stretch away into the
distance.

And if they were to turn to follow it over the course of the day, they would be turning left to right the whole time, and the sun would be moving from left to right the whole time, going up on the left and coming down on the right, like the hands of a clock — “clockwise”, as it were.

One correspondent suggested that perhaps many people in technologically advanced countries are not actually familiar with how the sun and moon move, and this was the cause of some of the confusion. Perhaps so, it's certainly tempting to dismiss my critics as not knowing how the sun behaves. The other possibility is that I am utterly confused. I took Observational Astronomy in college twice, and failed both times.

Anyway, I will maybe admit that “left to right” was unclear. But I will not recant my claim that the sun moves clockwise. E pur si muove in senso orario.

Sundials

Here I was just dead wrong. I said:

In the Northern Hemisphere, the shadow of a sundial proceeds clockwise, from left to right.

Absolutely not, none of this is correct. First, “left to right”. Here's a diagram of a typical sundial:

diagram of a hypothetical sundial with numbers
8,9,10,11,12,1,2,3,4 arranged clockwise in a
semicircle.

It has a sticky-up thing called a ‘gnomon’ that casts a shadow across the numbers, and the shadow moves from left to right over the course of the day. But obviously the sundial will work just as well if you walk around and look at it from the other side:

The
exact same diagram, but rotated 180 degrees.  The numerals are now
upside down.

It still goes clockwise, but now clockwise is right to left instead of left to right.

It's hard to read because the numerals are upside down? Fine, whatever:

The
exact same as previous, except that the numerals (and only the
numerals) have been rotated again, so they are right side up.

Here, unlike with the sun, “go around to the other side” is perfectly reasonable.

Talking with Joe Ardent, I realized that not even “clockwise” is required for sundials. Imagine the south-facing wall of a building, with the gnomon sticking out of it perpendicular. When the sun passes overhead, the gnomon will cast a shadow downwards on the wall, and the downward-pointing shadow will move from left to right — counterclockwise — as the sun makes its way from east to west. It's not even far-fetched. Indeed, a search for “vertical sundials” produced numerous examples:

wooden sundial mounted on a
brick wall; the numbers run counter-clockwise down the left edge from VII
to X, then along the bottom edge from XI through XII to II, and then
up the right edge from III to VI.

Sundial on the Moot Hall by David Dixon, CC BY 2.0 https://creativecommons.org/licenses/by/2.0, via Wikimedia Commons and Geograph.

Winter weather on July 4

Finally, it was reported that there were complaints on Hacker News that Australians do not celebrate July 4th. Ridiculous! All patriotic Americans celebrate July 4th.


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Sat, 13 Apr 2024

3-coloring the vertices of an icosahedron

I don't know that I have a point about this, other than that it makes me sad.

A recent Math SE post (since deleted) asked:

How many different ways are there to color the vertices of the icosahedron with 3 colors such that no two adjacent vertices have the same color?

I would love to know what was going on here. Is this homework? Just someone idly wondering?

Because the interesting thing about this question is (assuming that the person knows what an icosahedron is, etc.) it should be solvable in sixty seconds by anyone who makes the least effort. If you don't already see it, you should try. Try what? Just take an icosahedron, color the vertices a little, see what happens. Here, I'll help you out, here's a view of part of the end of an icosahedron, although I left out most of it. Try to color it with 3 colors so that no two adjacent vertices have the same color, surely that will be no harder than coloring the whole icosahedron.

The explanation below is a little belabored, it's what OP would have discovered in seconds if they had actually tried the exercise.

Let's color the middle vertex, say blue.

The five vertices around the edge can't be blue, they must be the other two colors, say red and green, and the two colors must alternate:

Ooops, there's no color left for the fifth vertex.

The phrasing of the question, “how many” makes the problem sound harder than it is: the answer is zero because we can't even color half the icosahedron.

If OP had even tried, even a little bit, they could have discovered this. They didn't need to have had the bright idea of looking at a a partial icosahedron. They could have grabbed one of the pictures from Wikipedia and started coloring the vertices. They would have gotten stuck the same way. They didn't have to try starting in the middle of my diagram, starting at the edge works too: if the top vertex is blue, the three below it must be green-red-green, and then the bottom two are forced to be blue, which isn't allowed. If you just try it, you win immediately. The only way to lose is not to play.

Before the post was deleted I suggested in a comment “Give it a try, see what happens”. I genuinely hoped this might be helpful. I'll probably never know if it was.

Like I said, I would love to know what was going on here. I think maybe this person could have used a dose of Lower Mathematics.

Just now I wondered for the first time: what would it look like if I were to try to list the principles of Lower Mathematics? “Try it and see” is definitely in the list.

Then I thought: How To Solve It has that sort of list and something like “try it and see” is probably on it. So I took it off the shelf and found: “Draw a figure”, “If you cannot solve the proposed problem”, “Is it possible to satisfy the condition?”. I didn't find anything called “fuck around with it and see what you learn” but it is probably in there under a different name, I haven't read the book in a long time. To this important principle I would like to add “fuck around with it and maybe you will stumble across the answer by accident” as happened here.

Mathematics education is too much method, not enough heuristic.


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Sun, 31 Mar 2024

Stuff that is backwards in Australia

I thought at first was going to be kind of a dumb article, because it was just going to be a list of banal stuff like:

  • When it's day here, it's night there, and vice versa

but a couple of years back I was rather startled to realize that in the Southern Hemisphere the sun comes up on the right and goes counterclockwise through the sky instead of coming up on the left and going clockwise as I have seen it do all my life, and that was pretty interesting.

Then more recently I was thinking about it more carefully and I was stunned when I realized that the phases of the moon go the other way. So I thought I'd should actually make the list, because a good deal of it is not at all obvious. Or at least it wasn't to me!

  1. When it's day here, it's night there, and vice versa. (This isn't a Southern Hemisphere thing, it's an Eastern Hemisphere thing.)

  2. When it's summer here, it's winter there, and vice versa. Australians celebrate Christmas by going to the beach, and July 4th with sledding and patriotic snowball fights.

  3. Australia's warmer zones are in the north, not the south. Their birds fly north for the winter. But winter is in July, so the reversals cancel out and birds everywhere fly south in September and October, and north in March and April, even though birds can't read.

  4. The sun in the Southern Hemisphere moves counterclockwise across the sky over the course of the day, rather than clockwise. Instead of coming up on the left and going down on the right, as it does in the Northern Hemisphere, it comes up on the right and goes down on the left.

  5. In the Northern Hemisphere, the shadow of a sundial proceeds clockwise, from left to right. (This is the reason clock hands also go clockwise: for backward compatibility with sundials.) But in the Southern Hemisphere, the shadow on a sundial goes counterclockwise.

  6. In the Southern Hemisphere, the designs on the moon appear upside-down compared with how they look in the Northern Hemisphere. Here's a picture of the full moon as seen from the Northern Hemisphere. The big crater with the bright rays that is prominent in the bottom half of the picture is Tycho.

    Photo of the moon as seen
from the Northern Hemisphere

    In the Southern Hemisphere the moon looks like this, with Tycho on top:

    Photo of the moon as seen
from the Northern Hemisphere

    Australians see the moon upside-down because their heads are literally pointing in the opposite direction.

  7. For the same reason, the Moon's phases in the Southern Hemisphere sweep from left to right instead of from right to left. In the Northern Hemisphere they go like this as the month passes from new to full:

    New moon, all dim Bright crescent on the right-hand edge Bright on the right half Bright except for a dim crescent on the left-hand edge Full moon, all bright

    And then in the same direction from full back to new:

    Full moon, all bright Bright except for a dim crescent on the right-hand edge Dim on the right half Dim except for a bright crescent on the left-hand edge New moon, all dim

    But in the Southern Hemisphere the moon changes from left to right instead:

    New moon, all dim Dim except for a bright crescent on the left-hand edge Dim on the right half Bright except for a dim crescent on the right-hand edge Full moon, all bright

    And then:

    Full moon, all bright Bright except for a dim crescent on the left-hand edge Bright on the right half Bright crescent on the right-hand edge New moon, all dim

    Unicode U+263D and U+263E are called FIRST QUARTER MOON ☽ and LAST QUARTER MOON ☾ , respectively, and are depicted Northern Hemisphere style. (In the Southern Hemisphere, ☽ appears during the last quarter of the month, not the first.) Similarly the emoji U+1F311 through U+1F318, 🌑🌒🌓🌔🌕🌖🌗🌘 are depicted in Northern Hemisphere order, and have Northern Hemisphere descriptions like “🌒 waxing crescent moon”. In the Southern Hemisphere, 🌒 is actually a waning crescent.

  8. In the Northern Hemisphere a Foucault pendulum will knock down the pins in clockwise order, as shown in the picture. (This one happens to be in Barcelona.) A Southern Hemisphere Foucault pendulum will knock them down in counterclockwise order, because the Earth is turning the other way, as viewed from the fulcrum of the pendulum.

  9. Northern Hemisphere tornadoes always rotate counterclockwise. Southern Hemisphere tornadoes always rotate clockwise.

Dishonorable mention

As far as I know the thing about water going down the drain in one direction or the other is not actually true.

Addendum 20240414

Several people took issue with some of the claims in this article, and the part about sundials was completely wrong. I wrote a followup.


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Fri, 08 Mar 2024

Werewolf ammunition

This week I read on Tumblr somewhere this intriguing observation:

how come whenever someone gets a silver bullet to kill a werewolf or whatever the shell is silver too. Do they know that part gets ejected or is it some kind of scam

Quite so! Unless you're hunting werewolves with a muzzle-loaded rifle or a blunderbuss or something like that. Which sounds like a very bad idea.

Once you have the silver bullets, presumably you would then make them into cartidge ammunition using a standard ammunition press. And I'd think you would use standard brass casings. Silver would be expensive and pointless, and where would you get them? The silver bullets themselves are much easier. You can make them with an ordinary bullet mold, also available at Wal-Mart.

Anyway it seems to me that a much better approach, if you had enough silver, would be to use a shotgun and manufacture your own shotgun shells with silver shot. When you're attacked by a werewolf you don't want to be fussing around trying to aim for the head. You'd need more silver, but not too much more.

I think people who make their own shotgun shells usually buy their shot in bags instead of making it themselves. A while back I mentioned a low-tech way of making shot:

But why build a tower? … You melt up a cauldron of lead at the top, then dump it through a copper sieve and let it fall into a tub of water at the bottom. On the way down, the molten lead turns into round shot.

That's for 18th-century round bullets or maybe small cannonballs. For shotgun shot it seems very feasible. You wouldn't need a tower, you could do it in your garage. (Pause while I do some Internet research…) It seems the current technique is a little different: you let the molten lead drip through a die with a small hole.

Wikipedia has an article on silver bullets but no mention of silver shotgun pellets.

Addendum

I googled the original Tumblr post and found that it goes on very amusingly:

catch me in the woods the next morning with a metal detector gathering up casings to melt down and sell to more dumb fuck city shits next month


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Wed, 06 Mar 2024

Optimal boxes with and without lids

Sometime around 1986 or so I considered the question of the dimensions that a closed cuboidal box must have to enclose a given volume but use as little material as possible. (That is, if its surface area should be minimized.) It is an elementary calculus exercise and it is unsurprising that the optimal shape is a cube.

Then I wondered: what if the box is open at the top, so that it has only five faces instead of six? What are the optimal dimensions then?

I did the calculus, and it turned out that the optimal lidless box has a square base like the cube, but it should be exactly half as tall.

For example the optimal box-with-lid enclosing a cubic meter is a 1×1×1 cube with a surface area of !!6!!.

Obviously if you just cut off the lid of the cubical box and throw it away you have a one-cubic-meter lidless box with a surface area of !!5!!. But the optimal box-without-lid enclosing a cubic meter is shorter, with a larger base. It has dimensions $$2^{1/3} \cdot 2^{1/3} \cdot \frac{2^{1/3}}2$$

and a total surface area of only !!3\cdot2^{2/3} \approx 4.76!!. It is what you would get if you took an optimal complete box, a cube, that enclosed two cubic meters, cut it in half, and threw the top half away.

I found it striking that the optimal lidless box was the same proportions as the optimal complete box, except half as tall. I asked Joe Keane if he could think of any reason why that should be obviously true, without requiring any calculus or computation. “Yes,” he said. I left it at that, imagining that at some point I would consider it at greater length and find the quick argument myself.

Then I forgot about it for a while.

Last week I remembered again and decided it was time to consider it at greater length and find the quick argument myself. Here's the explanation.

Take the cube and saw it into two equal halves. Each of these is a lidless five-sided box like the one we are trying to construct. The original cube enclosed a certain volume with the minimum possible material. The two half-cubes each enclose half the volume with half the material.

If there were a way to do better than that, you would be able to make a lidless box enclose half the volume with less than half the material. Then you could take two of those and glue them back together to get a complete box that enclosed the original volume with less than the original amount of material. But we already knew that the cube was optimal, so that is impossible.


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Mon, 04 Mar 2024

Children and adults see in very different ways

I was often struck with this thought when my kids were smaller. We would be looking at some object, let's say a bollard.

The kid sees the actual bollard, as it actually appears, and in detail! She sees its shape and texture, how the paint is chipped and mildewed, whether it is straight or crooked.

I don't usually see any of those things. I see the bollard abstractly, more as an idea of a “bollard” than as an actual physical object. But instead I see what it is for, and what it is made of, and how it was made and why, and by whom, all sorts of things that are completely invisible to the child.

The kid might mention that someone was standing by the crooked bollard, and I'd be mystified. I wouldn't have realized there was a crooked bollard. If I imagined the bollards in my head, I would have imagined them all straight and identical. But kids notice stuff like that.

Instead, I might have mentioned that someone was standing by the new bollard, because I remembered a couple of years back when one of them was falling apart and Rich demolished it and put in a new one. The kid can't see any of that stuff.


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Sun, 03 Mar 2024

Even without an alien invasion, February 22 on Talos I would have been a shitshow

One of my favorite videogames of the last few years, maybe my most favorite, is Prey. It was published in 2017, and developed by Arkane, the group that also created Dishonored. The publisher (Bethesda) sabotaged Prey by naming it after a beloved 2006 game also called Prey, with which it had no connection. Every fan of Prey (2006) who was hoping for a sequel was disappointed and savaged it. But it is a great, great game.

(I saw a video about the making of the 2017 Prey in which Raphael Colantonio talked about an earlier game of theirs, Dark Messiah of Might and Magic, which was not related to the Might and Magic series. But the publisher owned the Might and Magic IP, and thought the game would sell better if it was part of their established series. They stuck “Might and Magic” in the title, which disappointed all the Might and Magic fans, who savaged it. Then when Bethesda wanted to name Prey (2017) after their earlier game Prey (2006), Colantonio told them what had gone wrong the previous time they tried that strategy. His little shrug after he told that story broke my heart a little.)

This article contains a great many spoilers for the game, and also assumes you are familiar with the plot. It is unlikely to be of interest to anyone who is not familiar with Prey. You have been warned.

(If you're willing to check it out on my say-so, here's a link. I suggest you don't read the description, which contains spoilers. Just buy it and dive in.)


A recent question on Reddit's r/prey forum asked what would have happened if the Typhon organisms had not broken out when they did. The early plot of Prey is all there, but it is a little confusing, because several things were happening at once. The short answer to the question though, is that February 22, 2035 would have been the worst day of Alex Yu's life even if his magnificent space station hadn't been overrun by terrifying black aliens.

Morgan escapes the sim lab anyway

January had contingency plans for at least two situations. One was a Typhon escape, which we know all about.

But there was another plan for another situation. Morgan was having her memory erased before each round of testing. January explains that there was a procedure that was supposed to bring Morgan back up to speed after the tests were over. We know this procedure was followed for some time: Morgan's office has been used. Her assistant Jason Chang still hasn't gotten over his delight at working for such a hot boss. There are puzzled emails around asking why she never remembers her office combination. There's painful email from Mikhaila asking why Morgan is snubbing her. Clearly, at some point in the recent past, Morgan was still walking around the station in between tests, working and talking to people.

January's second contingency plan was in case Alex stopped bringing Morgan back up to speed after each round of tests, and just kept her in the simulation day after day — perhaps even more than once per day. (No wonder her eye is red!) And crucially, that plan was already in motion on February 22, the day the Typhon escaped.

The first thing that happens to the player in Prey is that Morgan fails all the tests. (“Is she…” “Yes, she's… hiding behind the chair.”) Why? We find out later Morgan was supposed to receive neuromods that would give her Typhon powers such as mimicry. They didn't. Marco Simmons says he installed exactly what Patricia brought down. There's email in the sim lab that asks Neuromod to check that something isn't wrong with the production process. But nothing is wrong with the production process. What really went wrong is that January had secretly replaced the neuromods with fakes, so that when they were removed from Morgan's brain, her memory wouldn't be affected. The next time Morgan woke up in her apartment and it was still March 15, she would realize what was happening.

It's hard to guess just what would have happened next, but I'm sure it would have been rather dramatic.

But that's not all

There are at least five other situations that would have blown up that same day. February 22 2035 on Talos I was always going to be an incredible shitshow.

  1. Emmanuel Mendez

    Because Frank Jones is a fuckup, Emmanuel Mendez has become aware that the escape pods don't work. He has decided to alert the crew by reprogramming the giant floating billboards to display “ESCAPE PODS ARE FAKE”. He completes this task on February 22 but dies without activating the program that will change the display.

    Those billboards are visible from everywhere on the station, including the cafeteria.

  2. Halden Graves

    Halden Graves, head of the Neuromod Division, has just figured out that the neuromods, even the non-Typhon ones, are made with exotic material from the Typhon, and he completely loses his shit, to the point of chopping open his own head to get them out. That might attract some attention.

  3. Josh Dalton

    On February 22, Josh Dalton murdered Lane Carpenter with the BFG 9000 and then fled with it into the GUTS.

  4. Alton Weber

    Weber is on the Life Support security team. He has had a paranoid breakdown and stolen a shotgun. There's probably going to be a firefight outside the Life Support restrooms.

  5. Mikhaila Ilyushin

    Mikhaila is about to be arrested. Alex already suspected that something about her was fishy. Mikhaila has sent Divya Naaz to install snooping devices in the doors in Psychotronics, and Divya has been caught. Alex isn't going to wait any longer to stop Ilyushin.

Coming soon

These are starting to fall apart but the shit won't really hit the fan until sometime after February 22.

  1. Annelise Gallegos and Quinten Purvis

    Annelise Gallegos has been overcome by her conscience and is blowing the whistle on the experiments in Psychotronics and the murder of the “Volunteers”. On February 22, Alex has ordered Sarah Elazar to arrest her, as soon as her shift is over. The Typhon escape prevents that. What would have happened to Gallegos? I suspect she would would have died in an ⸢unfortunate accident⸣.

    But it's too late for the Yus. Gallegos has already prepared her thumb drive with all the damning evidence, and Quinten Purvis has hidden with it in a cargo container. If the Typhon hadn't gotten loose that day, he would have been on his way to Earth with it.

    [ Addendum 20240327: There's a hint that Sarah Elazar is on the trail, and I think I remember that she has sent someone to investigate the cargo hold, but it's not clear that they would have been able to stop Purvis. ]

  2. Hunter Hale

    Shuttles are supposed to take the Volunteers back to Earth when their service is complete. The Shuttle Bay flight control staff have recently noticed that the shuttles are not going straight back to Earth, but are stopping somewhere else just after leaving, and then proceeding to Earth on a slightly altered course.

    What's really happening is that the shuttle pilot, Hunter Hale, makes a stop at the Psychotronics airlock and drops off some or all of the Volunteers so they can be turned into Neuromods.

    Alex is paying Hale five times the normal salary to keep his mouth shut about this, but HR has noticed and is asking questions about it. Between the flight control staff and HR, the truth is going to come out.

    [ Addendum 20240327: The security staff has brought the suspicious shuttle course to the attention of Sarah Elazar, who is going to investigate. ]

  3. Sarah Elazar

    Elazar suspects that the Yus are up to something dirty. She doesn't know what yet, but she's going to find out.

  4. Disappearing neuromods

    Everyone seems to be pilfering neuromods. Emmanuella Da Silva has some stashed in the drop ceiling of the Shuttle Bay locker room. Yuri Kimura has four under her desk, and Elias Black is blackmailing her. Lorenzo Calvino has some in both of his secret safes. Lily Morris has them hidden in the fire alarms in half a dozen places around the station. That dumbass Grant Lockwood has tried to walk back to Earth with his stolen neuromods.

    I probably missed a few, they're all over.

    (I said none of this would come to light until after February 22, but it won't be long before someone wonders what became of Lockwood. It's also possible Alex will find out about the Lily Morris conspiracy that day, from Eddie Voss. I almost feel sorry for Alex.)

    [ Addendum 20240327: Elazar, as usual, is on the ball. She knows Lockwood is missing and has dispatched someone to find him. ]

Minor shit

Not giant disasters, but troublesome nevertheless.

  1. Lorenzo Calvino

    It won't be long before someone, probably Miyu Okabe, figures out that Lorenzo Calvino has a severe, progressive mental impairment.

  2. Price Broadway

    Broadway, the alcoholic in Waste Processing, is endangering everyone's lives by leaving empty vodka bottles in the eel tanks. His supervisor knows and has reported him to HR. She says HR will help, but I imagine they'll just fire him.

    Maybe he'll end up on Hunter Hale's shuttle home.

  3. Volunteers

    What's up with the Volunteers in the dormitory in Neuromod Division? Some of them are stealing and selling supplies. Other are stealing dangerous equipment and weapons. What for?

Drama drama drama

Even without the Typhon, Prey could have been a great game!

You play Morgan, of course. The first fifteen minutes are the same, right up until Bellamy would have died.

When you wake up for the second time on March 15, you figure out what is happening, and confront the Sim Lab staff. You escape, go rogue, and make your way to the Arboretum to confront Alex. Meanwhile all sorts of stuff is going down. Alton Weber is on a rampage in Life Support. Josh Dalton is loose in the GUTS. You'll have to deal with him to get to the Arboretum. (What, did you think you were going to take the elevator?) Somewhere along the line you find out about Purvis in the cargo container and have to decide how to handle that. And then Mendez changes the billboards and there's a panic…

What else?

A lot is happening on Talos I. I probably left something out.

(The shortage of escape pods doesn't count. Someone would have noticed long ago that there aren't nearly enough. I think we have to assume that there are more escape pods than we see in the game. Perhaps Morgan's simulation omitted them.)

(And in my headcanon, that poor schmuck Kevin Hague never does find out his wife has cheated on him with the asshole football star.)

Let me know what I missed.


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Fri, 16 Feb 2024

Etymology roundup 2024-02

The Recurse Center Zulip chat now has an Etymology channel, courtesy of Jesse Chen, so I have been posting whenever I run into something interesting. This is a summary of some of my recent discoveries. Everything in this article is, to the best of my knowledge, accurate. That is, there are no intentional falsehoods.

Baba ghanouj

I tracked down the meaning of (Arabic) baba ghanouj. It was not what I would have guessed.

Well, sort of. Baba is “father” just like in every language. I had thought of this and dismissed it as unlikely. (What is the connection with eggplants?) But that is what it is.

And ghanouj is …
“coquetry”.

So it's the father of coquetry.

Very mysterious.

Eggnog

Toph asked me if “nog” appeared in any word other than “eggnog”. Is there lemonnog or baconnog? I had looked this up before but couldn't remember what it was except that it was some obsolete word for some sort of drink.

“Nog” is an old Norfolk (England) term for a kind of strong beer which was an ingredient in the original recipe, sometime in the late 17th or early 18th century.

I think modern recipes don't usually include beer.

Wow

“Wow!” appears to be an 18th-century borrowing from an indigenous American language, because most of its early appearances are quotes from indigenous Americans. It is attested in standard English from 1766, spelled “waugh!”, and in Scots English from 1788, spelled “vow!”

Riddles

Katara asked me for examples of words in English like “bear” where there are two completely unrelated meanings. (The word bear like to bear fruit, bear children, or bear a burden is not in any way related to the big brown animal with claws.)

There are a zillion examples of this. They're easy to find in a paper dictionary: you just go down the margin looking for a superscript. When you see “bear¹” and “bear²”, you know you've found an example.

The example I always think of first is “venery” because long, long ago Jed Hartman pointed it out to me: venery can mean stuff pertaining to hunting (it is akin to “venison”) and it can also mean stuff pertaining to sex (akin to “venereal”) and the fact that these two words are spelled the same is a complete coincidence.

Jed said “I bet this is a really rare phenomenon” so I harassed him for the next several years by emailing him examples whenever I happened to think of it.

Anyway, I found an excellent example for Katara that is less obscure than “venery”: “riddle” (like a puzzling question) has nothing to do with when things are riddled with errors. It's a complete coincidence.

The “bear” / “bear” example is a nice simple one, everyone understands it right away. When I was studying Korean I asked my tutor an etymology question, something like whether the “eun” in eunhaeng 은행, “bank”, was the same word as “eun” 은 which means “silver”. He didn't understand the question at first: what did I mean, “is it the same word”?

I gave the bear / bear example, and said that to bear fruit and to bear children are the same word, but the animal with claws is a different word, and just a coincidence that it is spelled the same way. Then he understood what I meant.

(Korean eunhaeng 은행 is a Chinese loanword, from 銀行. 銀 is indeed the word for silver, and 行 is a business-happening-place.)

Right and left

The right arm is the "right" arm because, being the one that is (normally) stronger and more adept, it is the right one to use for most jobs.

But if you ignore the right arm, there is only one left, so that is the "left" arm.

This sounds like a joke, but I looked it up and it isn't.

Leave and left

"Left" is the past tense passive of "leave". As in, I leave the room, I left the room, when I left the room I left my wallet there, my wallet was left, etc.

(As noted above, this is also where we get the left side.)

There are two other words "leave" in English. Leaves like the green things on trees are not related to leaving a room.

(Except I was once at a talk by J.H. Conway in which he was explaining some sort of tree algorithm in which certain nodes were deleted and he called the remaining ones "leaves" because they were the ones that were left. Conway was like that.)

The other "leave" is the one that means "permission" as in "by your leave…". This is the leave we find in "sick leave" or "shore leave". They are not related to the fact that you have left on leave, that is a coincidence.

Normal norms

Latin norma is a carpenter's square, for making sure that things are at right angles to one another.

So something that is normal is something that is aligned the way things are supposed to be aligned, that is to say at right angles. And a norm is a rule or convention or standard that says how things ought to line up.

In mathematics and physics we have terms like “normal vector”, “normal forces” and the like, which means that vectors or forces are at right angles to something. This is puzzling if you think of “normal” as “conventional” or “ordinary” but becomes obvious if you remember the carpenter's square.

In contrast, mathematical “normal forms” have nothing to do with right angles, they are conventional or standard forms. “Normal subgroups” are subgroups that behave properly, the way subgroups ought to.

The names Norman and Norma are not related to this. They are related to the surname Norman which means a person from Normandy. Normandy is so-called because it was inhabited by Vikings (‘northmen’) starting from the 9th century.

Hydrogen and oxygen

Jesse Chen observed that hydrogen means “water-forming”, because when you burn it you get water.

A lot of element names are like this. Oxygen is oxy- (“sharp” or “sour”) because it makes acids, or was thought to make acids. In German the analogous calque is “sauerstoff”.

Nitrogen makes nitre, which is an old name for saltpetre (potassium nitrate). German for nitre seems to be salpeter which doesn't work as well with -stoff.

The halogen gases are ‘salt-making’. (Greek for salt is hals.) Chlorine, for example, is a component of table salt, which is sodium chloride.

In Zulip I added that The capital of Denmark, Copenha-gen, is so-called because in the 11th century is was a major site for the production of koepenha, a Germanic term for a lye compound, used in leather tanning processes, produced from bull dung. I was somewhat ashamed when someone believed this lie despite my mention of bull dung.

Spas, baths, and coaches

Spas (like wellness spa or day spa) are named for the town of Spa, Belgium, which has been famous for its cold mineral springs for thousands of years!

(The town of Bath England is named for its baths, not the other way around.)

The coach is named for the town of Kocs (pronounced “coach”), Hungary, where it was invented. This sounds like something I would make up to prank the kids, but it is not.

Spanish churches

“Iglesia” is Spanish for “church”, and you see it as a surname in Spanish as in English. (I guess, like “Church”, originally the name of someone who lived near a church).

Thinking on this, I realized: “iglesia” is akin to English “ecclesiastic”.

They're both from ἐκκλησία which is an assembly or congregation.

The mysterious Swedish hedgehog

In German, a hedgehog is “Igel”. This is a very ancient word, and several other Germanic languages have similar words. For example, in Frisian it's “ychel”.

In Swedish, “igel” means leech. The hedgehog is “igelkott”.

I tried to find out what -kott was about. “kotte” is a pinecone and may be so-called because “kott” originally meant some rounded object, so igelkott would mean the round igel rather than the blood igel, which is sometimes called blodigel in Swedish.

I was not able to find any other words in Swedish with this sense of -kott. There were some obviously unrelated words like bojkott (“boycott”). And there are a great many Swedish words that end in -skott, which is also unrelated. It means “tail”. For example, the grip of a handgun is revolverskott.

[ Addendum: Gustaf Erikson advises me that I have misunderstood ‑skott; see below. ]

Bonus hedgehog weirdness: In Michael Moorcock's Elric books, Elric's brother is named “Yyrkoon”. The Middle English for a hedgehog is “yrchoun” (variously spelled). Was Moorcock thinking of this? The -ch- in “yrchoun” is t͡ʃ though, which doesn't match the stop consonant in “Yyrkoon”. Also which makes clear that “yrchoun” is just a variant spelling of “urchin”. (Compare “sea urchin”, which is a sea hedgehog. or compare “street urchin”, a small round bristly person who scuttles about in the gutter.)

In Italian a hedgehog is riccio, which I think is also used as a nickname for a curly-haired or bristly-haired person.

Slobs and schlubs

These are not related. Schlub is originally Polish, coming to English via (obviously!) Yiddish. But slob is Irish.

-euse vs. -ice

I tried to guess the French word for a female chiropractor. I guessed “chiropracteuse" by analogy with masseur, masseuse, but I was wrong. It is chiropractrice.

The '‑ice' suffix was clearly descended from the Latin '‑ix' suffix, but I had to look up ‘‑euse’. It's also from a Latin suffix, this time from ‘‑osa’.

Jot

When you jot something down on a notepad, the “jot” is from Greek iota, which is the name of the small, simple letter ι that is easily jotted.

Bonus: This is also the jot that is meant by someone who says “not a jot or a tittle”, for example Matthew 5:18 (KJV):

For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled.

A tittle is the dot above the lowercase ‘i’ or ‘j’. The NIV translates this as “not the smallest letter, not the least stroke of a pen”, which I award an A-plus for translation.

Vilifying villains

I read something that suggested that these were cognate, but they are not.

“Vilify” is from Latin vīlificō which means to vilify. It is a compound of vīlis (of low value or worthless, I suppose the source of “vile”) and faciō (to make, as in “factory” and “manufacture”.)

A villain, on the other hand, was originally just a peasant or serf; that is, a person who lives in a village. “Village” is akin to Latin villa, which originally meant a plantation.

Döner kebab

I had always assumed that “Döner” and its “ö” were German, but they are not, at least not originally. “Döner kebab” is the original Turkish name of the dish, right down to the diaresis on the ‘ö’, which is the normal Turkish spelling; Turkish has an ‘ö’ also. Döner is the Turkish word for a turning-around-thing, because döner kebab meat roasts on a vertical spit from which it is sliced off as needed.

“Döner” was also used in Greek as a loanword but at some point the Greeks decided to use the native Greek word gyro, also a turning-around-thing, instead. Greek is full of Turkish loanwords. (Ottoman Empire, yo.)

“Shawarma”, another variation on the turning-around-vertical-spit dish, is from a different Ottoman Turkish word for a turning-around thing, this time چویرمه (çevirme).

The Armenian word for shawarma is also shawarma, but despite Armenian being full of Turkish loanwords, this isn't one. They got it from Russian.

Everyone loves that turning-on-a-vertical-spit dish. Lebanese immigrants brought it to Mexico, where it is served in tacos with pineapple and called tacos al pastor (“shepherd style”). I do not know why the Mexicans think that Lebanese turning-around-meat plus pineapples adds up to shepherds. I suppose it must be because the meat is traditionally lamb.

Roll call

To roll is to turn over with a circular motion. This motion might wind a long strip of paper into a roll, or it might roll something into a flat sheet, as with a rolling pin. After rolling out the flat sheet you could then roll it up into a roll.

Dinner rolls are made by rolling up a wad of bread dough.

When you call the roll, it is because you are reading a list of names off a roll of paper.

Theatrical roles are from French rôle which seems to have something to do with rolls but I am not sure what. Maybe because the cast list is a roll (as in roll call).

Wombats and numbats

Both of these are Australian animals. Today it occurred to me to wonder: are the words related? Is -bat a productive morpheme, maybe a generic animal suffix in some Australian language?

The answer is no! The two words are from different (although distantly related) languages. Wombat is from Dharug, a language of the Sydney area. Numbat is from the Nyungar language, spoken on the other end of the continent.

Addendum

Gustaf Erikson advises me that I have misunderstood ‑skott. It is akin to English shoot, and means something that springs forth suddenly, like little green shoots in springtime, or like the shooting of an arrow. In the former sense, it can mean a tail or a sticking-out thing more generally. But in revolverskott is it the latter sense, the firing of a revolver.


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Wed, 14 Feb 2024

The pleasures of dolmen-licking

Ugh, the blog has been really stuck lately. I have lots of good stuff in process but I don't know if I will finish any of it, which would be a shame, because it's good stuff and I have put a lot of work into it. So I thought maybe I should make an effort to relax my posting standards for a bit. In fact I should make an effort to relax them more generally. But in particular, today. So,

here is a picture of me licking a dolmen.

A
slightly balding dark-haired man with glasses is leaning slightly as
he sticks out his tongue to touch a massive rectangular stone that is
resting at head height atop smaller upright stones.  In the background
are a green hill and a stone wall.  The man has his hands in the
pockets of his blue jeans and is wearing a blue denom jacket.

Here is Michael G. Schwern licking the same dolmen.

A bearded man with a great deal of long curly hair is leaning
over to lick the same stone table as in the other picture.  The day is
much brighter and sunnier.  He is wearing blue jeans, an olive-colored
sweater, and has his hands clasped behind him.

Not on the same day, obviously. As far as I know we were not in the country at the same time. The question is in my mind: who was the first of us to lick the dolmen? I think he was there before me. But I also wonder: when I decided to lick it, did I know he had done the same thing? It's quite possible that Marty Pauley or someone said to me “You know, when Schwern was here, he licked it,” to which I would surely have responded “then I shall lick it as well!” But it's also possible that we licked the dolmen completely independently, because why wouldn't you? How often to you get a chance to taste a piece of human prehistory?

As a little kid you discover that the world is full of all sorts of fascinating stuff that you may be allowed to look at, but not to touch, and certainly not to climb on or to lick. (“Don't put it in your mouth!”) Dolmens are a delightful exception to this rule. Sure, lick the dolmen all you want. It has stood in the same place for five thousand years, and whether it stands there for five thousand more will not be affected by any amount of licking.

My inner four-year-old was very satisfied the day I licked the dolmen. I imagine that Schwern felt the same way.


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Tue, 06 Feb 2024

Jehovah's Witnesses do not number the days of the week

[ Content warning: Rambly. ]

Two Jehovah's Witnesses came to the door yesterday and at first I did not want to talk to them but as they were leaving I remembered that I had a question. I asked them what they called the days of the week. They were very puzzled by this because it turns out that they call them Monday, Tuesday, Wednesday, Thursday, and so on, just like everyone else in this country. They were so puzzled that they did not even take the opportunity to continue the conversation. They thanked me for coming to the door, and left.

I found this interesting. The reason I had asked is that the JW religion is very strict regarding paganism. For example, they do not observe Christmas or Easter, because these holidays, to them, have a suspicious pagan origin. A few months ago I had wondered: do they celebrate Thanksgiving? I thought it was possible. As far as I know it has no pagan connection at all, and an observance of giving thanks to Jehovah seemed consistent with their beliefs. No, it turns out that they don't, on the principle that to single out one special day might lead them to neglect to give proper thanks to Jehovah on the other days.

So, I wondered, if they object to Easter, how do they feel about the days of the week? To speak of Tuesday, Wednesday, Thursday, and Friday is to honor the pagan Germanic gods Tyr, Odin, Thor, and Frigg, and I thought they might object to this also. The Quakers referred to the days of the week as First Day, Second Day, and so on for this reason. But the issue appears to have flown under the JWs' radar.

I didn't ask about the months, assuming that if they didn't cringe when speaking of Thor's Day, they wouldn't have a problem with the month of Janus (the two-faced god of boundaries) or with Maia (her fertility festival is in May) or with the month of the deified person of Roman Emperor Augustus.

I have a sense that Quakers are generally more sophisticated thinkers than Jehovah's Witnesses. They objected to the names of the months also, but decided it would be too confusing to change them. But they saw their opportunity in 1752, when the Kingdom of Great Britain finally brought its calendar in line with the rest of Europe. Along with the other calendrical changes, the Quakers agreed amongst themselves to start calling the months after numbers instead of the old-style names.

I had a conversation once with Larry Wall, who is himself a devout Christian. We were talking about Jehovah's Witnesses, because at that time there was a prominent member of the Perl community who was one. Larry, not at all a venomous person, said with some venom, that the JWs were “a cult”.

“A ‘cult’?” I asked. “What do you mean?” People often use the word cult as a pejorative for “sect” or religion: a cult is any religion that I don't like. But Larry, as usual, was wiser and more thoughtful than that. He said that he called them a cult because you are not allowed to leave. If you do, the other JWs, even your close friends and your family, are no longer allowed to associate with you, and if they do, they may be threatened with expulsion.

I thought that seemed like a principled definition, and it has served me since then. Sometimes, encountering other organizations from which it was difficult to extract onesself, I have heard Larry's voice in my mind, saying “that's a cult”. Thanks, Larry.

I have a draft article about how Larry Wall is my model for a rational, admirable Christian, but I'm not sure it is ever going to come together.


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Sat, 16 Dec 2023

My Git pre-commit hook contained a footgun

The other day I made some changes to a program, but when I ran the tests they failed in a very bizarre way I couldn't understand. After a bit of investigation I still didn't understand. I decided to try to narrow down the scope of possible problems by reverting the code to the unmodified state, then introducing changes from one file at a time.

My plan was: commit all the new work, reset the working directory back to the last good commit, and then start pulling in file changes. So I typed in rapid succession:

git add -u
git commit -m 'broken'
git branch wat
git reset --hard good

So the complete broken code was on the new branch wat.

Then I wanted to pull in the first file from wat. But when I examined wat there were no changes.

Wat.

I looked all around the history and couldn't find the changes. The wat branch was there but it was on the current commit, the one with none of the changes I wanted. I checked in the reflog for the commit and didn't see it.

Eventually I looked back in my terminal history and discovered the problem: I had a Git pre-commit hook which git-commit had attempted to run before it made the new commit. It checks for strings I don't usually intend to commit, such as XXX and the like.

This time one of the files had something like that. My pre-commit hook had printed an error message and exited with a failure status, so git-commit aborted without making the commit. But I had typed the commands in quick succession without paying attention to what they were saying, so I went ahead with the git-reset without even seeing the error message. This wiped out the working tree changes that I had wanted to preserve.

Fortunately the git-add had gone through, so the modified files were in the repository anyway, just hard to find. And even more fortunately, last time this happened to me, I wrote up instructions about what to do. This time around recovery was quicker and easier. I knew I only needed to recover stuff from the last add command, so instead of analyzing every loose object in the repository, I did

find .git/objects -mmin 10 --type f

to locate loose objects that had been modified in the last ten minutes. There were only half a dozen or so. I was able to recover the lost changes without too much trouble.

Looking back at that previous article, I see that it said:

it only took about twenty minutes… suppose that it had taken much longer, say forty minutes instead of twenty, to rescue the lost blobs from the repository. Would that extra twenty minutes have been time wasted? No! … The rescue might have cost twenty extra minutes, but if so it was paid back with forty minutes of additional Git expertise…

To that I would like to add, the time spent writing up the blog article was also well-spent, because it meant that seven years later I didn't have to figure everything out again, I just followed my own instructions from last time.

But there's a lesson here I'm still trying to figure out. Suppose I want to prevent this sort of error in the future. The obvious answer is “stop splatting stuff onto the terminal without paying attention, jackass”, but that strategy wasn't sufficient this time around and I couldn't think of any way to make it more likely to work next time around.

You have to play the hand you're dealt. If I can't fix myself, maybe I can fix the software. I would like to make some changes to the pre-commit hook to make it easier to recover from something like this.

My first idea was that the hook could unconditionally save the staged changes somewhere before it started, and then once it was sure that it would complete it could throw away the saved changes. For example, it might use the stash for this.

(Although, strangely, git-stash does not seem to have an easy way to say “stash the current changes, but without removing them from the working tree”. Maybe git-stash save followed by git-stash apply would do what I wanted? I have not yet experimented with it.)

Rather than using the stash, the hook might just commit everything (with commit -n to prevent infinite loops) and then reset the commit immediately, before doing whatever it was planning to do. Then if it was successful, Git would make a second, permanent commit and we could forget about the one made by the hook. But if something went wrong, the hook's commit would still be in the reflog. This doubles the number of commits you make. That doesn't take much time, because Git commit creation is lightning fast. But it would tend to clutter up the reflog.

Thinking on it now, I wonder if a better approach isn't to turn the pre-commit hook into a post-commit hook. Instead of a pre-commit hook that does this:

  1. Check for errors in staged files
    • If there are errors:
      1. Fix the files (if appropriate)
      2. Print a message
      3. Fail
    • Otherwise:
      1. Exit successfully
      2. (git-commit continues and commits the changes)

How about a post-commit hook that does this:

  1. Check for errors in the files that changed in the current head commit
    • If there are errors:
      1. Soft-reset back to the previous commit
      2. Fix the files (if appropriate)
      3. Print a message
      4. Fail
    • Otherwise:
      1. Exit successfully

Now suppose I ignore the failure, and throw away the staged changes. It's okay, the changes were still committed and the commit is still in the reflog. This seems clearly better than my earlier ideas.

I'll consider it further and report back if I actually do anything about this.

Larry Wall once said that too many programmers will have a problem, think of a solution, and implement it, but it works better if you can think of several solutions, then implement the one you think is best.

That's a lesson I think I have learned. Thanks, Larry.

Addendum

I see that Eric Raymond's version of the jargon file, last revised December 2003, omits “footgun”. Surely this word is not that new? I want to see if it was used on Usenet prior to that update, but Google Groups search is useless for this question. Does anyone have suggestions for how to proceed?


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Fri, 15 Dec 2023

Recent addenda to articles 202311: Christenings in Tel Aviv

[ Content warning: extremly miscellaneous. ]

Wow, has it really been 7 months since I did one of these? Surprising, then, how few there are. (I omitted the ones that seemed trivial, and the ones that turned into complete articles.)

  • Back in 2018 I wrote an article that mentioned two alleys in Tel Aviv and quoted an article from Haaretz that said (in part):

    A wealthy American businessman … had christened the streets without official permission… .

    Every time I go back to read this I am brought up short by the word “christened”, in an article in Haaretz, in connection with the naming of streets in Tel Aviv. A christening is a specifically Christian baptism and naming ceremony. It's right there in the word!

    Orwell's essay on Politics and the English Language got into my blood when I was quite young. Orwell's thesis is that language is being warped by the needs of propaganda. The world is full of people who (in one of Orwell's examples) want to slip the phrase “transfer of population” past you before you can realize that what it really means is “millions of peasants are robbed of their farms and sent trudging along the roads with no more than they can carry”. Writers are exposed to so much of this purposefully vague language that they learn to imitate it even when they are not trying to produce propaganda.

    I don't mean to say that that's what the Haaretz writer was doing, intentionally or unintentionally. My claim is only that in this one case, because she wasn't thinking carefully about the meanings of the words she chose, she chose a hilariously inept one. Because of an early exposure to Orwell, that kind of mischoice jumps out at me.

    This is hardly the most memorable example I have. The prize for that belongs to my mother, who once, when she was angry with me, called me a “selfish bastard”. This didn't have the effect she intended, because I was so distracted by the poor word choice.

    Anyway, the Orwell thing is good. Brief and compelling. Full of good style advice. Check it out.

  • In 2019, I wrote an article about men who are the husbands of someone important and gave as examples the billionaire husband of Salma Hayek and the Nobel prizewinning husband of Marie Curie. I was not expecting that I would join this august club myself! In April, Slate ran an article about my wife in which I am referred to only as “Kim's husband”. (Judy Blume's husband is also mentioned, and having met him, I am proud to be in the same club.)

  • Also, just today I learned that Antoine Veil is interred in the Panthéon, but only because he was married to Simone Veil.

  • In an ancient article about G.H. Hardy I paraphrased from memory something Hardy had said about Ramanujan. In latter years Hardy's book become became available on the Internet, so I was able to append the exact quotation.

  • A few years ago I wrote a long article about eggplants in which I asked:

    Wasn't there a classical Latin word for eggplant? If so, what was it? Didn't the Romans eat eggplant? How do you conquer the world without any eggplants?

    I looked into this a bit and was amazed to discover that the Romans did not eat eggplant. I can only suppose that it was because they didn't have any, poor benighted savages. No wonder the Eastern Roman Empire lasted three times as long.


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