This is a system of length units devised for Borrowers, somewhat by analogy to the imperial units and various other customary unit systems. This would probably be used by borrowers in Europe and the USA that picked up some concepts from various European civilizations but applied them in their own way. Though for the most part, borrowers probably ended up switching to metric in official terms like the rest of the world did. Borrowers probably also standardized on the standard human timekeeping system (thank GOODNESS for that).

The borrower foot: About one fifth of body height, at around 3 cm (probably around 3.05, but the exact value matters less than the intuition for worldbuilding purposes). Slightly shorter than a borrower's foot, or the height of a borrower's head, and slightly longer than a borrower's hand. Related to the conventional 1:2:2 head:torso:legs height proportions for a borrower.

The borrower "stat": Six feet. About a foot more than the height of the average borrower. ~18 cm. 2-2.5 stats is the standard ceiling height.

The borrower "hop": Four stats. Approximately the height that the average borrower can jump to, 24 feet. ~72 cm. A borrower can cross this distance in about a second at a casual movement speed. The borrower "bound": Six hops. Approximately the width of the largest gap the average borrower can be expected to fully consistently clear with a running jump. ~432 cm, 144 feet. The borrower "kent": 100 bounds. No particular structural meaning, but continues the system and provides a standard "long" unit of measurement. ~432 meters. 14400 feet.

And on the other side:

Most of my borrowers don't actually have an issue with running into standard humans, it's mainly just the commensal ones that do it... largely out of tradition/to avoid interfering with the standard humans/to avoid unpredictable scenarios, basically. Their eyes probably have slightly worse resolution, due to being physically smaller, although they probably wouldn't be as nearsighted as you might expect since their movement abilities are surprisingly similar to those of standard humans in terms of absolute scale. Their hearing is more sensitive to higher pitched sounds and their voices are high pitched as well, about 1-2 octaves higher than standard human voices (it would geometrically be about 3-4 octaves, but humans already have a really wide variance and there are several morphological adaptations that end up preventing a full geometric scaling). I could also imagine it being more sensitive overall, if they're smaller (I gave them somewhat large ears relative to their head size), due to adaptations to avoid predators and such, although to deal with cats their main detection mechanism would be sight.

As for sense of smell, I don't really quite know how exactly it would scale with size. I'm roughly just modeling it as kinda like a standard human.

This part will cover the interior layouts of borrower houses. All of the builds in this section are at 1:11 scale, such that the player character is borrower-sized.

I find it quite reasonable that a borrower's house would not really have "floors" in the same sense as a standard human's house would.

Instead, the interior layout of a house may look a little something like this. Here, instead of staircases, we have floors on different sides of the house that can be jumped between. Ceilings are also taller, giving more room for verticality in a given room (for a regular human they'd be 2.5-3 blocks tall, which may seem weird if you're familiar with Minecraft building conventions, but interestingly enough most Minecraft buildings are roughly built at 1:1.5 or so rather than 1:1.)

The walls of a borrower house are rough, in order to make climbing around the interior as easy as possible. The areas made of bricks here probably have the bricks notably jut out a little.

The first thing to notice about borrower furniture is that seats are much wider than they would be if they were proportionally scaled down. Minecraft's 1-(relative)-meter grid actually works out in our favor here, since that's about how wide a chair would end up being. This is simply because borrowers have much bigger butts relative to their height - while our chairs are roughly cubic, theirs would be wider than they are tall.

I don't think fireplaces are affected much by size, but feel free to correct me if I'm wrong. Also in this image can be seen the ceiling hooks for hanging from that can also be seen in the image in my intro post. Just a way to fit more people around a fireplace.

(The little "live, laugh, love" poster on the wall is actually from my much older attempt at a borrower house build, from before I had a lot of what I know now figured out.)

The step down from the living room is the basement. This room exists at all just due to the way the floors are staggered on different sides of the house, requiring one floor to be either inset into the ground somewhat or have an uncomfortably low ceiling (at least for a borrower). This room is just used as, well, a basement. It has some technical stuff for the house in it, along with

I haven't stepped through it thoroughly yet, but I could see a reason why art supplies couldn't scale down as much as they would if fully proportional. So anyway, I have this room here. Not much else to say.

Here's the gym: in-universe this'd probably be sort of a gym/playground hybrid of sorts. I always sorta found the idea funny of a borrower-sized hamster wheel used as a treadmill. Anyway, the weights on the right match a borrower's carrying capacity: 1lb (comfortable carry, probably reasonable 1-hand lift) and 8lb.

But honestly, borrowers probably get enough exercise from jumping around the house as it is. With little risk of injury, there'd be little motive for "make everyone sedentary NOW". (Also, note that there are no railings. The highest fall in the house is about 2 meters, which is fine for a borrower, and it's easy for you to scramble up to where you were.)

Computer/electronics would probably hit their limit at about the equivalent of... laptop/tablet-size for borrowers. Standard TVs/computers would be essentially Homo sapiens smartphones, this is an older somewhat larger model.

I've given most bedrooms a two-story layout with an upper level that has the bed. It's kinda more cozy that way. This particular one is located behind the computer area.

And another bedroom - the hanging lantern doubles as a bedside lamp.

Here's the kitchen. Fridges are HUGE - again, a lot of storage is needed for the large amounts of food being prepared. The kitchen is probably one of the more active rooms in the house. I've also added an upper level with some extra appliances that might not scale down well, such as an air fryer.

Additionally, I'd see borrowers having a lot more reliance on sealed containers. They're easier to just toss up to the next floor before climbing up there.

Houses probably have these elevator systems (pictured at center). They're for moving more fragile or difficult to handle objects up and down, as well as elderly or disabled Borrowers. Weight limit: this one's a pretty simple structure, so not THAT high (borrowers don't need fancy cable-based elevators like standard humans use, they probably just need something with a simple pulley or some extending zigzag beams), but still enough to carry basically any object you'd want to carry up or down.

Here's the rooftop. It's accessible by jumping up from a platform that would connect this house to a neighboring one, or by using some hooks to navigate under and around the overhang.

Also, the exterior of the house has all these ledges that make navigation easy. The windows are all also probably openable, so they can function as doors.

The rooftop garden probably isn't quite scale-accurate (should have more dirt) but it gets the right idea across. Just the sense of the roof as an actual space where things exist.

Hello Frisk256! Borrower housing is probably very vertical. Not only do borrowers traverse multiple floors easily, the height of a "floor" itself is probably taller than it would be for a proportional human, to allow them to jump over and around things more easily. Think 30-45 inches or 2-3 body lengths. Additionally, the square footage of a house scales down by x50 rather than by x120, because borrowers are proportionally wider than standard humans.

This is the average square footage of a borrower family home (at 1:1 block scale), assuming similar household sizes to America.

Of course, a borrower house is usually gonna have all these rooms stacked on top of each other, like this (also at 1:1 block scale):

Let's start with the outside. Borrower houses aren't usually separate buildings. They're often more interconnected, like this (1:5 scale):

This post will go over various physiology characteristics and physical abilities that borrowers have.

Deviantart link for full-res version: https://www.deviantart.com/vectorv9260/art/hosted-for-tumblr-1356158118

Carrying:

Okay, so most of human weight lifting statistics are like, a really controlled exercise rather than an actual measurement of human capacity to move stuff around. I estimate that an average standard human could comfortably carry about 15 pounds; the analogous number for a borrower is about 1 pound. Notably, this is about 2-3x the body weight of a borrower, meaning that a borrower could rather easily carry a lightweight platform with two other borrowers on it.

Metabolism:

I didn't show it here, but a borrower probably needs to eat about 15-20% their body weight per day. Crude scaling laws would suggest about 13%, but I've rounded it up given the unusually large brain for a creature of this size. To put that in context, relative to body mass, that's a meal about the size of what a human eats in a day - six times a day! Or in terms of familiar foods, a slice of an apple.

Movement:

Walking speed (well, an exertion of energy similar to human fast-walking) is about 0.7 m/s, but sprinting bursts are about 5 meters per second. Vertical jumps are about 0.7 meters high, meaning a borrower can grab onto a ledge that's almost a full meter above their ground level. Climbing sufficiently rough surfaces (drywall? wood?) is easy, and is almost as fast as the thing I've called "walking" here. Probably wall running for a limited time as well, wall kicks, etc.

Reaction time is about 2x faster than a normal human, and additionally borrowers can take basically any fall with only minor injury, or without injury at all if they land correctly (which is also why they have some reflexes that are faster than their normal reaction time).

Overall, borrowers produce a surprising match for the behavior of... a platformer character! Like, in a 3d platformer where you're jumping around and sprinting and such and you're doing things that a human isn't normally able to do, and gravity is way faster than it is IRL... except if you assume the protagonist is borrower-sized, in which case everything lines up basically perfectly.

First, normalize the height by dividing by 1.7. The height of a borrower is about 0.09 in these units.

Then, there are 3 cases:

k < 0.114: 4.075k^3 - 5.5k^4 (avoiding extreme proportions at small sizes)

0.114 <_ k < 1.3757: k^2.43 (BMI)

k >_ 1.3757: k^4/1.65 (square-cube law takes over)

And finally, the result is multiplied by 63 to get the weight in kilograms (about 0.15 for borrowers).

In other words, the borrowers in the Borrower Project are not intended to be "scaled-down humans", they are instead "humans but 6 inches tall", in the same way Homo floresiensis are humans but 3 feet tall and your tall friend is a human but 6 and a half feet tall.

Additionally, the proportions in question were heavily inspired by LeapantLZR's stylization of "borrowers", which gave them about the head size and body width shown here. @leapant

Behold: Borrowers!

The proportions in the image are entirely realistic - no "chibification" has happened.

Borrowers have been chosen to be 6 inches tall, matching the original lore specifying them at about 5-6 inches. For some reason, a lot of G/T media shrinks borrowers down further to about 3-4 inches. I am not quite sure what the reason for this is, but as a rule, height scales at 1:11.

I've rationalized the borrowers' extremely small size as the result of a kind of "runaway neoteny", where human social instincts cause populations to drift towards more childlike features to an extreme extent, essentially as if it's a variable constantly trying to be twice itself, until it hits the lower limit before human cognition breaks down.

These "borrowers" are designed after archaic humans rather than after standard humans, due to themselves being related to archaic lineages such as Homo antecessor in this interpretation.

Additionally, only a small portion of the population is actually regularly interacting with standard humans or in human environments.

What are Borrowers?

Borrowers are a species of miniature (~6 inches tall) human first formalized by Mary Norton with her book "The Borrowers" and based on mythologies established prior to that point. Borrowers are consistently depicted with a lifestyle that is commensal to standard humans, living in hidden places in the homes of standard humans (such as attics and crawl spaces) and scavenging dropped or abandoned food and objects while staying out of sight of standard humans themselves; the name "borrower" describes this lifestyle, being the self-description of the protagonists of Mary Norton's book. Borrowers are notable for having been picked up as the "default" small human variant in specific online spaces focused on "giant/tiny" scenarios and interactions (G/T, also often described as a fetish or "macro/micro"), due to their lifestyle facilitating such interactions rather easily.

What is the Borrower Project?

The Borrower Project is a project intending to create a biologically and societally coherent version of borrowers as a fantasy race, essentially going through the actual physical implications of a humanoid species being 6 inches tall, and how things like society, architecture, and transportation would develop around that. This species is also to be incorporated into a "parallel history" for the real world, in which they exist on Earth alongside standard humans, although since the focus in moreso on the "borrowers" themselves than their relation with standard humans, most borrowers will be living outside of standard human settlements entirely, in their own communities, with only a small fraction retaining the commensal lifestyle. I'm also aiming to get some community engagement with this project in the case that it gets popular enough for that to make sense.

How will the project be presented?

In large part, information about the project will be presented as polished Tumblr posts like the one you are reading, often including visual graphics. This account will also post the creator's random thoughts about the project in order to allow for the wider web to engage with the project. Most architectural specifications will be presented as Minecraft or Hytale builds with a specified scale, as that is the 3D medium I find easiest to use for applications like this.

What is a parallel history?