Imperial or Metric?

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gentlemanbear

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I am in the process of writing a medieval fantasy product and I was wondering whether I should quote imperial measures still in general use in the US (which came from those used from the medieval period until England adopted the metric system generally in 1965) with metric translations or save myself the trouble of providing metric translations, as well. (England is the cultural frame of reference)
What are your thoughts?
 

Ravenswing

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I suppose it depends on your market. Steve Jackson's response to those grousing that he'd moved from metric in TFT to imperial in GURPS had to do with that the great majority of the people buying it were from the United States. Further, the climate for acceptance of metric changed a good bit: in the Seventies, when highway signs in America were listing distances in km and liter liquid measurements came into vogue, the notion that metric was our future was far from outlandish.

If you're going for period verisimilitude ... mmm. Aside from that medieval weights and measures weren't remotely standardized, I've seen very few products that attempted to push ells, tuns, roods, virgates or pottles on players. (And that's just English post-Conquest measures.)
 
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TristramEvans

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I always provide both. The US is a huge market, but the rest of the world uses metric, so either way it's cutting off a large group of readers from instinctual understanding
 

CRKrueger

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Medieval Fantasy, I’d use Imperial, and as many old timey measurements like the ones Ravenswing is referring to as you can find.
 

Trippy

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Contrary to popular belief, the Imperial Measurement system, as established in the British Empire, was only codified in the 19th century (1824) after the Metric system had already been established in post-Revolution France (c. 1790). Britain officially stopped using Imperial measurements and switched to metric some time in the 1960s - but a lot of people still use them (sign posts are all in Miles still, for example). The USA and Cuba are the only places, internationally, that still officially use Imperial, but even then, scientific papers have to comply with S.I. measurements (metric).

The Imperial terms themselves were older, but they weren’t regulated at all - different regions actually varied wildly in the units they measured. If you want to get an authentic medieval set of units, from medieval Spain at least, you could do no better than look at those used in Aquelarre.
 

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David Johansen

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I like metric for science fiction. Doing stuff like calculating courses or building GURPS Vehicles in Imperial is madness. I like Imperial a little better in day to day use and in fantasy though I lean towards paces, spans, and cubits.
 

spittingimage

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I always provide both. The US is a huge market, but the rest of the world uses metric, so either way it's cutting off a large group of readers from instinctual understanding
Most of us have some idea of what inches, feet, yards and miles are. (You know what a metric pint is? A bloody rip-off is what it is.) My parents grew up using the Imperial system.

I think I'd find it immersion-breaking to find centimetres, decimetres and kilometres in medieval fantasy.
 

Trippy

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Most of us have some idea of what inches, feet, yards and miles are. (You know what a metric pint is? A bloody rip-off is what it is.) My parents grew up using the Imperial system.

I think I'd find it immersion-breaking to find centimetres, decimetres and kilometres in medieval fantasy.
This is true for Americans, primarily.

However, I also find it immersion breaking when Imperial measurements are used in science fiction games - it has turned me off GURPS: Traveller and Transhuman Space before. In fantasy games, I generally don’t use measurements in any strict way, aside from distances occasionally.
 

Ravenswing

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Medieval Fantasy, I’d use Imperial, and as many old timey measurements like the ones Ravenswing is referring to as you can find.

Not hard. What those of you without extensive medieval libraries want is this: https://en.wikipedia.org/wiki/Template:Systems_of_measurement -- that's a template with current and historical units, and moreover historical units by nationality. Screw those western Eurocentric medieval things! (I like, for instance, that traditional Mongolian units of measurement include the örtöö, which is a third of a day's ride on a horse, and multiples thereof. Or that a Nepali unit of measure of length is a "bow grip," approximately three inches, and that they've a unit of volume that's a "fistful.")
 

TristramEvans

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I think I'd find it immersion-breaking to find centimetres, decimetres and kilometres in medieval fantasy.

As opposed to a system from the 19th century?

I'm referring to an explanation of the system, I prefer to do that in a way as accessible as possible to the reader, to assist in GM's making judgement calls as needed. For the characters in the world, whatever that may be, I'd use a system far more appropriate. For the Middle Ages that certainly isn't the Imperial system of measurements, established in 1824, replacing the Winchester standards instituted in the 16th century.
 

AsenRG

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I am in the process of writing a medieval fantasy product and I was wondering whether I should quote imperial measures still in general use in the US (which came from those used from the medieval period until England adopted the metric system generally in 1965) with metric translations or save myself the trouble of providing metric translations, as well. (England is the cultural frame of reference)
What are your thoughts?
Depends. If you're talking about the system, metric all the way in my book! The people who use imperial would know the conversion rates, should they wish to use them.
If it's about the characters in setting? They can use whatever is appropriate for the time period and place.
 

Séadna

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I prefer metric because it's the system I think in, but with the US being a bigger market for games I've no real problem with games using Imperial since it's not hard to do the conversion. One interesting case in this regard is the Chronicles of Darkness system which gives distances in an abstract unit that you can take as either a yard or meter depending on which you prefer. If you work through it metric vampires are slightly more powerful (not always though).

In game as others said I'd probably throw in the ones suited to the time and place. China and Japan had really interesting and complex measurement units prior to the 19th century that I've gotten good use out of.
 

Trippy

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As an aside, it is probably also worth mentioning another popular misconception with the Imperial system - that pounds and ounces are not, in fact, the equivalent to kilograms and grams. Pounds are a measure of weight, whereas kilograms are a measure of mass. That is, pounds are the amount of force applied due to gravity by a mass - and therefore are dependent on the gravity in effect, while kilograms are a measure of inertia due to mass (and is currently defined in relation to Planck’s constant and the speed of light).

The actual metric equivalent of pounds are Newtons, while the Imperial equivalent of kilograms are slugs (and blobs). There has been methods to differentiate measurements, mainly in the US I think, to refer to Pound-Mass and Pound-Force units, although in general use there remains a confusion I feel.
 

Séadna

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Funnily enough in modern physics calculations you measure mass by how much extra space it generates by warping spacetime, so for instance the Sun's mass is 1.5 km. Similarly time is measured in meters (since it's just another dimension like space).
That's why the speed of light is ~300,000 km/s, it's basically telling you a second is "really" 300,000 km in the temporal direction. Most of the fundamental constants are conveying some equivalence like this.
 

Stumpydave

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Expecting my knight to know its 17 kilometres to Gastonbury would throw me out of the game enough to not go back.
Imperial (or older) for fantasy, Metric for sci fi.
 

burbles

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This may be a stupid question, but does it really matter?

Maybe it’s only my experience, but how often do you expect it to come up during play, and what’s its importance to the (your) product?

As some people have already posted, anything large in terms of length can be related to hours/days of riding, days of sailing. Smaller distances could be related to number of paces/ or say as long as your forearm.

I’m Australian, but am old enough to remember (?) a number of conversions for imperial to metric ie 1 km is approximately 5/8 mile. 1 yard is approx 1m.

Personally I hate things in imperial, but if your product is good enough that won’t stop me from buying it. :smile:
 

finarvyn

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I grew up in the US and was in high school in the late 1970's, and at the time they were teaching conversions like crazy because everyone said we'd be moving to metric "soon" and of course it still hasn't happened. This means I tend to think in imperial, since that was the system I learned early on. However, as a physics teacher everything I calculate is in metric because it's the language of science and it's so much easier.

I agree that having both is probably useful. I also agree that science fiction games ought to be in metric.
 

Black Leaf

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Yeah, this one probably depends on who you think your main core demographic is likely to be.

US is obviously imperial.

Mainland Europe is largely metric.

The UK is officially metric, but you'll find everyone from Gen X upwards largely thinks in imperial. People still get a pint of lager and talk about distances in miles, not kilometers. Even kids will often talk about taking a penalty from 12 yards.
 

Silent Green

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Meh. I'm more at home with metric, but it doesn't feel appropriate for (faux-)medieval stuff. The local 3.5oz pygmy marmoset RPG uses metric with more or less invented terms (1m = 1 "pace", 1kg = 1 "stone", etc.). Imperial? No problem: A yard is a meter, a pound is a pound, three miles is 5km and so forth. Using "faux-culturally appropriate weights and measures" would annoy me severely ("the barge moves at a leasurely 36 Pirsean dick-widths per standard Semurian fart-duration", er, no thanks).
 

Black Leaf

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Although for money I'd just use pounds, shillings and pence and not bother going for full accuracy.
 

CRKrueger

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As opposed to a system from the 19th century?

I'm referring to an explanation of the system, I prefer to do that in a way as accessible as possible to the reader, to assist in GM's making judgeent calls as needed. For the characters in the world, whatever that may be, I'd use a system far more appropriate. For the Middle Ages that certainly isn't the Imperial system of measurements, established in 1824, replacing the Winchester standards instituted in the 16th century.
Eh, that’s not the whole story, though. Much of the Imperial system is simply standardising measurements that were somewhat variable, but very old. The inch goes back to at least the 700s and a very close equivalent to the foot goes back to ancient Egypt.
 

Silent Green

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Also, NASA lost a $125 million spacecraft/Mars probe in 1999 when they failed to convert imperial to metric measurements.
https://www.latimes.com/archives/la-xpm-1999-oct-01-mn-17288-story.html
Tarkin: "Navigator, why do I not see Alderaan filling the cockpit window?"
Navigator: "I'm sorry, you Moffship, looks like we're in the middle of nowhere."
Tarkin: "I'm quite sure I did say 'take me to Alderaan', not 'middle of nowhere', didn't I."
Navigator: "You did, your Moffship, and I put it into the nav console. We dropped early, and there's nothing out here, not even enough interstellar hydrogen to register. There must be something wrong with the drive."
Tarkin: "Engineering, why did we drop out of hyperspace?"
Engineering: "Er, I'm sorry, your Moffship, we're out of gas."
Tarkin: "What is this nonsense? We filled up the tank when we stopped at the Dantooine ConchErg. Don't you remember? You all got a Hoth Smoothie."
Engineering: "Er, yes, but there was this problem with the purser."
Purser: "I've got nothing to do with that! It's not my fault they don't accept Imperial Express."
Tarkin: "I explicitly told you to use my personal credit card."
Purser: "And I did, but as I wanted to keep the disturbance of your Moffship's funds at a minimum, we only bought exactly the... just a moment... 186423.23 florp we needed, just as the Chief told me."
Engineering: "That's correct, 186423.23 Republican florp for 944.2 megazirks of distance, just as the Navigator told me."
Navigator: "Um... yes, that's what the nav console says. 944.2 megazirks to Alderaan."
Purser: "Er, it says 186423.23 Imperial florp on the receipt. You didn't say nothing about Republican florp!"
Engineering: "Republic florp for Republic zirks."
Navigator: "That's 944.2 Imperial megazirks by the way."
Tarkin: "I'll retire. Vader, force-choke the lot of them until they think of something."
Navigator: "No, no, I have an idea: We launch all our TIE fighters, land them face-down in the equator trench and fire up their ion engines. That would take us to the next gas station in... about two days says the triple-S-chart."
Vader: "What kind of station is that?"
Navigator: "JawaCo."
Vader: "Oh, bloody hell. Do it."
Engineering: "Remove the proton torpedoes first! I'm not having a live proton torpedo in the vicinity of that exhaust chute!"
 

Ravenswing

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Although for money I'd just use pounds, shillings and pence and not bother going for full accuracy.

"Full accuracy" for currency is a whole hell of a lot WORSE than weights and measures. An element the more honest medieval economists raise in their works -- often in the preface -- is that we only have a vague idea of how much money was worth in medieval times. And even there, relative values weren't any more stable than they are now. (Quick, folks, how many dollars is the pound sterling worth right now? How much was it worth 20 years ago? 50 years ago? A century ago?)

This is something I've been studying for many years, going over countless sources, trying to get it "right" ... before I just had the Chair Leg of Truth come down on my pointy noggin and realize that I never would. Just assign fiat values and don't worry about it. And if in your "medieval" fantasy game the relative price of a good meal is skewed vis-a-vis the relative price of a good sword as it would go in 12th century England (as opposed to 10th century Tuscany, 15th century Burgundy, 13th century Scotland, 9th century Maharashtra ...), meh. Few players will notice, fewer still will care.
 

Fenris-77

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I use imperial for fantasy and metric for sci fi, much like Brock Savage Brock Savage . In fantasy games I tend to refer to distance in terms of time anyway, which is both more accurate to the period and easier to digest on the player end.
 

Andrew J. Luther

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Since you're talking about the use in a product you're writing, I'm just going to focus on that. I use the measurement system for the game I'm writing for. If the game uses metric, I'll include the (rough) imperial measurement in brackets afterward, just because the US is a big market. For example, in an upcoming product for Mythras, my measurements are like this:
  • 1 square = 1.5 meters (5 feet)
For the D&D 5E version, it looks like this:
  • 1 square = 5 feet
Unless you are creating a product that is not for any existing game system, I would just use the primary measurement system that is used for that game, so as to be consistent with other products in the line.

As an aside, what I find weird is that the U.S. is officially a metric country by legislation, but they didn't make conversion mandatory, so it was only implemented in certain industries (like medicine). I wouldn't want to work in an industry that uses metric while living in a country where literally nothing else uses it. Talk about a pain in the ass :tongue:.
 

Fenris-77

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Imperial! Resist our metric overlords!
ddtmuj9-3122ec57-a757-44ab-826e-368938d5ee81.jpg
 

Duskwight

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I am very lazy and just go with whatever the setting is already using. Right now that's Imperial in both my Pendragon and my FF14 game*.

*That setting uses Imperial with a very silly convention of using "fulm" for foot and "ilm" for inch and so on. After years of play I sometimes find it difficult to code-switch back and forth between games.
 

TristramEvans

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Eh, that’s not the whole story, though. Much of the Imperial system is simply standardising measurements that were somewhat variable, but very old. The inch goes back to at least the 700s and a very close equivalent to the foot goes back to ancient Egypt.

Sorta, yeah, but that's when an inch meant the width of a thumb, and a yard meant the span of an arm. And at various times you had stuff like lines, chains, furlongs, and rods alongside.
 

Venger Satanis

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I am in the process of writing a medieval fantasy product and I was wondering whether I should quote imperial measures still in general use in the US (which came from those used from the medieval period until England adopted the metric system generally in 1965) with metric translations or save myself the trouble of providing metric translations, as well. (England is the cultural frame of reference)
What are your thoughts?

USA, USA, USA, USA, USA, USA, USA!!!
 

ffilz

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This is true for Americans, primarily.

However, I also find it immersion breaking when Imperial measurements are used in science fiction games - it has turned me off GURPS: Traveller and Transhuman Space before. In fantasy games, I generally don’t use measurements in any strict way, aside from distances occasionally.
What version of Traveller? Classic Traveller has always been metric, though the 1.5m square is awfully conveniently close to 5' (3m is 9.84 feet, i.e. less than 2% off).

Personally I use the measurement system of the game system I'm using, and remember a bunch of simple conversions.

If accuracy is not necessary, sometimes it's convenient for 1m to be 1 yard, otherwise I use 3m is 10'. For longer distances, 8km is 5 miles is easy enough to do.

If I really need to convert between pounds and kilograms, I use 2.2 pounds to the kilogram. Or I whip out a conversion calculator.

I very rarely use volume measurements, but 1 liter as 4 gallons is close enough.
 

Brock Savage

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I grew up in the US and was in high school in the late 1970's, and at the time they were teaching conversions like crazy because everyone said we'd be moving to metric "soon" and of course it still hasn't happened.
My relationship with metric feels like I spent the formative years of my life grokking a foreign language that I almost never got to use. I graduated in '92 but those of us who grew up in GATE, AP, IB etc had metric seared into our young brains because metric is the language of science and the future. Then it was off to the Marine Corps which used metric for distance and ammunition presumably as part of some NATO compatibility requirement. For the remainder of my life, metric has gone largely unused besides a little bit in college or RPG stuff. Edit: I realize tools use metric but someone doesn't need to know a millimeter from a furlong to use a metric socket wrench.
 
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CRKrueger

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Sorta, yeah, but that's when an inch meant the width of a thumb, and a yard meant the span of an arm. And at various times you had stuff like lines, chains, furlongs, and rods alongside.
And pipes, and tuns, and pecks, and grains, all that good stuff. You toss it all in for a medieval campaign.

Edit - and make sure to have all kinds of different currencies.
 
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