Model Rail
Model Rail
[Cueball to the left and his friend, who also looks like Cueball, are standing in the friend's rather large basement, where the celling is held up by six thin columns, and the walls are shown angling in towards a point of perspective, to display how big the room is.] Friend: I want to build a perfect HO-scale (~1/87) model train layout of my town. Cueball: In your basement? Bad idea. Never make a layout of the area you're in.
[Zoom in on the two friends without the basement visualized.] Friend: Why not? Cueball: Because it'd include a little 10" replica of your house.
[Zoom in Cueball's friend who takes his hand to his chin.] Friend: So? That's be cool! I'd make tiny replicas of my rooms, my furniture— Cueball (off-screen)l: —And your train layout?
[Beneath this first row of the comic is the zoom-out of how the full model would look in the basement. The town lies beneath some small mountains. There is some water with a bridge over it continuing to the roads going through the city. There is no frame around this section, but instead there follows five zoom-outs, each one going from the friend's house, that proceeds to a circular frame. Within each of these is shown a nested model. Starting to the right of the main model, and then moving down, then left, and then down and right. Each layer has a broken arrow above the model between two vertical lines to indicate the scale, the length being written between the two parts of the arrow. Some foreign objects are also labeled to help understand the scale.]
[Layer 1, the model with the two friends standing to the left of it.] 18 m
[Layer 2, looks exactly as the model, but without the friends.] 21 cm
[Layer 3, with a mosquito shown for comparison. It stands over half the model covering the mountains.] 2.4 mm
[Layer 4, with a strand of spider silk (labeled) shown for comparison. The silk is much thicker than the roads, almost as thick as the mountains and much longer than the model. But the model still looks fairly much like the original one.] 28 μm Spider web
[Layer 5, with a cold virus (labeled) shown for comparison. It covers roughly a quarter of the model, taking up the water part of the model. At this level the whole model becomes notably "fuzzy" as individual atoms are discernible, and most of the features apart from the mountain is indiscernible. There may be two viruses. The other would then be to the right of the one in the water but above the model. The label stands between them.] 320 nm Cold virus
[Layer 6, is simply spheres (atoms) at this point. The mountain near the back is the only noticeable feature, consisting of five atoms jutting out from the surface of atoms, which is by no mean flat.] 37 Å
[Beneath these six versions of the model is a caption:] The Matryoshka limit: It is impossible to nest more than six HO layouts
[Back to the two friends in the basement, still not showing the basement.] Friend: My God. Cueball: Yeah. It's the second rule of model train layouts: No nesting.
[Zoom in on the heads of the two friends.] Friend: ...What's the first rule? Cueball: "Do not talk about model train layouts." That rule was actually voted in by our friends and families. Friend: Philistines.

In model rail construction, the HO scale refers to the most popular scale for modeling railroads, in which 3.5 millimeters in the model corresponds to 1 real-world Imperial foot. As the comic suggests, it works out to a ratio of about 1:87.1 (or 3048:35 exactly, which equals 1:87.08̄5̄7̄1̄4̄2̄8). In Europe, the scale is defined as exactly 1:87 instead, to avoid references to non-metric measurements.
This comic features two Cueballs conversing; we'll refer to them as Lefty and Righty to avoid confusion. The conversation takes place in Lefty's basement. Lefty is apparently a less-experienced train modeler, and he tells Righty that he wants to make an HO model layout of his town. However, the more-experienced Righty points out that this is a bad idea, due to nesting. To make it a perfectly accurate model, Lefty would have to include a model of his house, which includes his basement, which includes the model. So, he would have to make a model of the model, which will include a smaller model of the model, and so forth. This is illustrated in the comic.
At the end of these six nested models The Matryoshka limit is stated: "It is impossible to nest more than six HO layouts". Matryoshka dolls are toys of Russian origin that can be stacked inside one another. Here, the "Matryoshka limit" is the hard barrier that follows as a result of the nesting. Matter is not infinitely divisible; once one gets to the level of atoms, it is impossibly difficult to go any smaller. The unit shown in the last diagram is the ångström , a very small unit of measurement (1/10000th of a micrometre , 1/10 of a nanometre , 100 picometres or 10 −10 m) which was created when humans started discovering objects on an atomic scale, such as crystal structures or wavelengths. The last nested model looks like the atoms on a surface as seen using a scanning tunneling microscope (STM).
The rules of model train layouts reference the 1999 cult classic Fight Club , where the first rule of Fight Club is "do not talk about Fight Club." However, while the club instituted the rule because their activities were morally and legally questionable, the rule in the comic was instituted by friends and family members who were apparently sick of hearing the train enthusiasts talk about model train layouts all the time.  The second rule of Fight Club is "you do not talk about Fight Club", repeated for emphasis, but evidently Cueball and his friend are good enough at following the first rule of model train layouts that they only had to be told once.
The "Philistines" comment is not referring to citizens of ancient Philistia (at least not directly), but rather the philosophy of Philistinism . Friedrich Nietzsche defined a Philistine as someone who is purely negative in how they define style, i.e. they know exactly what they hate and don't really have anything they like. A common stereotype for artists is to refer to anyone who dislikes their work as "Philistines," thus dismissing their criticism as being part of a larger personality defect on the critic's part rather than any particular failing of the artwork in question.
The title text references HO scale and, more specifically, whether it should be spelled with the letter "O" or the number zero (0). Such debates often seem petty to the "layman", yet the people involved in the debates can form very strong feelings for their side. Randall recognizes "nerdy tendencies" almost immediately when he gets the urge to take a side.
[Cueball to the left and his friend, who also looks like Cueball, are standing in the friend's rather large basement, where the celling is held up by six thin columns, and the walls are shown angling in towards a point of perspective, to display how big the room is.] Friend: I want to build a perfect HO-scale (~1/87) model train layout of my town. Cueball: In your basement? Bad idea. Never make a layout of the area you're in.
[Zoom in on the two friends without the basement visualized.] Friend: Why not? Cueball: Because it'd include a little 10" replica of your house.
[Zoom in Cueball's friend who takes his hand to his chin.] Friend: So? That's be cool! I'd make tiny replicas of my rooms, my furniture— Cueball (off-screen)l: —And your train layout?
[Beneath this first row of the comic is the zoom-out of how the full model would look in the basement. The town lies beneath some small mountains. There is some water with a bridge over it continuing to the roads going through the city. There is no frame around this section, but instead there follows five zoom-outs, each one going from the friend's house, that proceeds to a circular frame. Within each of these is shown a nested model. Starting to the right of the main model, and then moving down, then left, and then down and right. Each layer has a broken arrow above the model between two vertical lines to indicate the scale, the length being written between the two parts of the arrow. Some foreign objects are also labeled to help understand the scale.]
[Layer 1, the model with the two friends standing to the left of it.] 18 m
[Layer 2, looks exactly as the model, but without the friends.] 21 cm
[Layer 3, with a mosquito shown for comparison. It stands over half the model covering the mountains.] 2.4 mm
[Layer 4, with a strand of spider silk (labeled) shown for comparison. The silk is much thicker than the roads, almost as thick as the mountains and much longer than the model. But the model still looks fairly much like the original one.] 28 μm Spider web
[Layer 5, with a cold virus (labeled) shown for comparison. It covers roughly a quarter of the model, taking up the water part of the model. At this level the whole model becomes notably "fuzzy" as individual atoms are discernible, and most of the features apart from the mountain is indiscernible. There may be two viruses. The other would then be to the right of the one in the water but above the model. The label stands between them.] 320 nm Cold virus
[Layer 6, is simply spheres (atoms) at this point. The mountain near the back is the only noticeable feature, consisting of five atoms jutting out from the surface of atoms, which is by no mean flat.] 37 Å
[Beneath these six versions of the model is a caption:] The Matryoshka limit: It is impossible to nest more than six HO layouts
[Back to the two friends in the basement, still not showing the basement.] Friend: My God. Cueball: Yeah. It's the second rule of model train layouts: No nesting.
[Zoom in on the heads of the two friends.] Friend: ...What's the first rule? Cueball: "Do not talk about model train layouts." That rule was actually voted in by our friends and families. Friend: Philistines.
