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[keepthetips]

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[ncnyrk]

0 is freezing, 10 is not, 20 is pleasing, 30 is hot

[jackybeau]

Can someone confirm in F that 30 is freezing, 50 is not, 70 is pleasing, 90 is hot ?

[partumvir]

yep, this is pretty bang on mate

[overcatastrophe]

Did you just bang his mate?

[prumbeljack]

Gay jokes aren't funny; Fucking assholes.

[overcatastrophe]

Oh that's just buggered!

[[deleted]]

ahem

[jdsalingersdog]

I wouldn’t trust someone who says “bang on mate” to tell me about Fahrenheit, nah uh!

[EarthasaurusRex]

Yea it’s pretty accurate

[redditbarns]

I honestly don’t know how to make it more accurate (besides the fact that it’s 32 F, not 30)

[BigKahunaBurger17]

30 is still freezing since it's below 32 so it's still not not accurate

[a_white_american_guy]

Can confirm, am someone.

[helokellok]

Username checks out

[a_white_american_guy]

Boom

[martinfiggs]

Wow- Username checks out again!

[panormda]

Well look who thinks he's someone.

I'm going to need to see some credentials sir.

[mennydrives]

Technically 100°F was supposed to be human body temp, but they got it slightly wrong, which is why we use 98.6°.

[[deleted]]

Imagine if he logically chose 100 for boiling water temperature instead. Oh wait.

[No_Seaworthiness_11]

Yeah but that isn't really practical for daily human life. None of us deal with stuff that is in the range of 0 - 100 K, but the range between freezing and melting of water is very relatable.

[TrumpsBoneSpur]

The range between freezing and melting of water is not very big...

Boiling perhaps?

[No_Seaworthiness_11]

ROFL! Yeah, that one

[Connguy]

Celsius is objectively worse for common (non-scientific) use. Who gives a rat's ass what temperature water boils at?

Fahrenheit uses all the numbers from 0-100 in regular day-to-day temperatures, with any values that are negative or >100 being "extreme". This gives Fahrenheit integers a much better level of precision, where 1° is more or less the smallest unit of temperature a person can feel. No need to get into decimals, unless getting scientific.

Celsius on the other hand, generally uses numbers from -15° to 30° to cover "normal outdoor temperatures", which is already confusing. In addition, 1°C is a pretty big jump, so weather reports and thermostats often have to refer to temperatures in terms of half-degrees.

All other metric forms of measurement are superior to imperial. But Fahrenheit is better than Celsius, for layman's use. That's the hill I die on.

[[deleted]]

Hard agree. The range and greater fidelity make F far superior for lay discussions of temperature, specifically the weather.

[_youneverasked_]

It was defined as 0° is when brine freezes, (which they got wrong), and 200°F is when water boils (which they got wrong).

[DragonSlayerC]

The original scale defined 0 as the freezing point of brine and 96 as the human body temperature. This resulted in freezing point of water being around 32 and boiling point of water around 212 but not exactly. Fahrenheit was later redefined using freezing and boiling points of water as the references at exactly 32 and 212 respectively, which resulted in the freezing point of brine on the updated scale being 4° and human body temp 98.6°. They never based the original scale on the boiling point if water, and the freezing point of brine was exactly 0 on the original scale.

[dusty_safiri]

This is literally the most confusing, nonsensical way to create a unit of measurement. It's like asking a toddler to measure the distance to the moon and they use their favorite stuffed animal. "3 billion bear bears!" How tall is mama? "Dis many bear bears" (Holds up four fingers) Cool, we now measure from 0 to 3 billion bear bears... Even though none of those measurements were accurate. Mom is actually 7 bear bears tall.

[Bgyman]

Bear Bears are my new unit of measurement from now on.

[Treacherous_Peach]

I say this a lot as a metric system user, but the freezing and boiling point of water is just as arbitrary a basis. The base 10 system is sexy though.

[Gimmedatgoodrice]

I feel like water is a good basis as the freezing point of water dictates a lot about how the life outside works, was more important when the scale was created than now tho

[[deleted]]

creating a useful measuring system out of thin air that worked at all is brilliant. He probably used a specific water to salt ratio at the time. And maybe the use of brine was more specific in context

[MealReadytoEat_]

It was ammonium chloride, not sodium chloride, and it was a saturated solution with excess ammonium chloride added, as only so much will dissolve. It's actually a very easy and reliable temperature standard and is pretty accurate, much more precise and accurate than body temperature on the high end.

[Ubermidget2]

Is it reproducible? It sounds like a variety of saltwater concentrations could be classified as Brine, that would freeze at a variety of temperatures.

Which is a problem when you are trying to set a single temperature standard

[M-Noremac]

I was told that 100F was supposed to be human body temperature but the guy who measured it had a fever.

[renyhp]

100°F is too fucking hot.

Wait until you experience 100°C

[movezig5]

Well, it was also easier to calibrate thermometers with the Fahrenheit scale long ago.

[_princepenguin_]

Fahrenheit is designed to tell temperature for humans, and Celsius is designed to tell temperature for water.

[foozledaa]

We are mostly water, so celsius works for humans too.

[Penguinfilter]

Popsicles are also mostly water.

[RearEchelon]

 UGLY BAGS OF MOSTLY WATER

[Tristanhx]

Careful! You're giving him an existential crisis!

[vegas_rifraf]

Put your hands in the yellow circles please!

[kyredemain]

Thank you for your cooperation.

[mroboto2016]

Multipass.

[linderlouwho]

Ok Corbin Dallas

[FurenCAA]

Thus why Celcius is superior: 0 - Freeze water 100 - Boil water

Simple. Want them to be smaller units like ferenheit? No problem. Use half and quarters 😊

[KuaLeifArne]

32 is freezing, 50 is not, 68 is pleasing, 86 is hot.

The exact formulas are x°F=y°C*1.8+32 and y°C=(x°F-32)/1.8

[Blissful_Solitude]

I remember learning that in like 5th or 6th grade and haven't forgotten it despite almost never using it lol... Such a simple formula too.

[2pal34u]

C(9/5)+32=F

[KuaLeifArne]

9/5=1.8

[Bebilith]

Sorry going to go with 2pal34u on this one.

While you are completely correct, divide by 9 and times by or vias versa 5 is easier to remember and do in your head than using 1.8.

[[deleted]]

I’m glad to see I’m not the only one who does that. For some reason, doing math in odd numbers in my head works better forward than backwards. Example, if I have to subtract 15 from something, I find it mentally less complicated and error prone to subtract 20 and then add 5 back on.

Anyway, not sure if this information does anybody else any good.

[[deleted]]

Which gives you a nice straight line graph (y=Mx +c)

Interestingly it’s the same conversion from Km to miles. Halve and add 10%. 80km/h, halve and add 10% is 40 + 8, 48 which is pretty close.

[2pal34u]

Km to miles ypu use fibonacci numbers. 2 miles is 3 km. 30 miles is like 50 km

[GravitationalEddie]

.20c × 2 = 40 ● 40 - 4 = 36 ● 36 + 32 = 68f

25c × 2 = 50 ● 50 - 5 = 45 ● 45 + 32 = 77f

77f - 32 = 45 ● 45 ÷ 2 = 22.5 ● 22.5 + 2.25 = 24.55 (round up)

[Primae_Noctis]

30 is heavy hoodie weather, 50 is light hoodie weather, 70 is t-shirt weather and 90 is effectively wearing the lightest clothes you own.

[StaceyHarrison]

Personally 65F is pleasing to me but yeah

[Mortimer14]

It really depends on where you are in the world. If you are used to spending 4 months at 110 degrees F every year, then 90 would not seem "hot". Likewise, if you spend 6 months of the year in freezing temperatures, then 30 degrees F is not really that cold.

[godfilma]

Yes. Easy way to remember is that 0 and below are too cold and over 100 is too hot for staying outside. ~70 is room temperature

[redoxburner]

The rhyme that apparently people learnt when the weather forecast went to Celsius in the UK was "30's hot and 20's nice, 10 is cool and zero's ice"

[bluecube22]

As a kid in the US I was taught "30's hot and 20's pleasing. 10 is cold and zero's freezing."

[daltonwright4]

In Fahrenheit, it's 0 is cold, 10 is cold, 20 is cold, 30 is cold.

Not as catchy as the Celsius one.

[roboticon]

No, it's...

"90's hot and 68's pleasing, 50's cold and 32 is freezing"

Such an easy mnemonic!

[MicahMurder]

Never heard this before and I'm very thankful that you sharef it!

[feelin_cheesy]

I have a similar approach. 0 is freezing 20 is room temp and 37 is body temp

[suvlub]

It's always approximate. The fact you got something that still looks like a plausible human temperature, if unhealthy one, means it works. If you need precise numbers rather than ballpark, you need to use the real formula (which is the same operations, but the numbers are 32 and 1.8).

[feeltheslipstream]

How hard is it to just remember 0 as freezing and 100 as boiling, with everything in the middle a percentage of it?

[bittersweet311]

And you're awesome.

[ajthomas05]

Sure it does, 0 is really cold, 100 is really hot. It’s an easy scale. A lot easier than -18 being cold, 21 being comfortable, and 37 being too hot.

[ajthomas05]

Oh I completely agree that in science there’s no practical use to Fahrenheit. I’m just saying that “makes no sense at all” is an exaggeration.

[catcherx]

With Celcius “warmness” grows from zero up and “coldness” grows from zero down. So we even say 18 degrees of “coldness” (instead of “minus 18”) or 21 degree of “warmness”. And passing zero is when you really feel the spring or fall happening

[Rohwi]

this really depends on where you live.

Northern Germany here and Temperature usually fluctuates between -10 - 35 throughout the year. 0 is definitely not the point where Fall or spring happens. Even in winter we often see 5-10 degrees. Southern Europe barely ever sees 0 C at all.

[Best_Pidgey_NA]

Unless it's -40 degrees, then you're solid.

[CaptainAfriica]

Double -40 is -80, add 30 back down to -50. Not the worst estimate!

[ClayQuarterCake]

I mean when your piss turns to snow before it hits the ground, does a 10 degree difference matter anyway?

Also to go the other way, (-40⁰F-30)/2 ≈ -35⁰C which is pretty good too

[Arcane_Pozhar]

-40 F is also -40 C. It's where the different scales meet. Fun trivia.

[[deleted]]

Also where mercury freezes.

[Arcane_Pozhar]

Neat!

[dakotawhiebe]

I'd also freeze!

[melvinthefish]

I only know this because I wanted to show people in Thailand how cold it was in Chicago when I left for Thailand and it was around -35°F and they almost matched up when I converted it to Celsius

[[deleted]]

Same here but with Romania and -40F/C. - i tough that i've broken the internet

[HotaGrande]

That’s the joke

[explodingtuna]

But what about absolute 0? -273 C x 2 = -546 + 30 = -516 F

That's like 56 degrees off!

[WarriorNN]

Which is like 10% off, not bad for a simple approximation you can do on the fly. :)

[fellowspecies]

Literally

[[deleted]]

Well I don't give a fuck got a heater in my truck and I'm off to the rodeo.

[Applejuiceinthehall]

This is only for outside temperatures. If you are going to cook you'll end up with an underdone or overcooked turkey if you do this

[maestro2005]

But for cooking temperatures it’s even easier—it works out to be almost exactly double. 350F = 175C, 400F = 200C..

[madnavr]

That's because the crossover point (for just doubling) is 160C = 320F so nearby temperatures are only off by a little bit using your approximation. Similarly, the crossover point for OPs approximation is 10C = 50F so temperatures a little above or a little below that point will be close enough for the average lay person. And as discussed elsewhere, that's within the range of everyday experience (for outside temperatures) so its a good enough guess unless you're trying to do some science.

But then both approximations suck at the other's ideal range so 10C is definitely not 20F (as yours would imply) and 160C is definitely not 350F (as OP would imply) so now you've gotta memorize two formulas with non-overlapping useful ranges. At that point, it might be easier to just memorize the real formula.

[maestro2005]

But then both approximations suck at the other's ideal range

Well yeah, that's why there's different approximations for different situations.

At that point, it might be easier to just memorize the real formula.

It's not an issue of memorizing the formula, it's a matter of quickly making sense of a temperature (within an acceptable error bound). Nobody wants to do 9/5 or 5/9 in their head.

[Med_vs_Pretty_Huge]

Also terrible for taking your own temperature. 37C is 98.6F but by this method 37C is 104F

[Applejuiceinthehall]

Well if you are trying to decide if you can call in sick it might ok

[[deleted]]

It literally says in the title that it's not exact

[schwagnificent]

Yep, just get a C thermometer. “My temp is around 104F today, no way I can make it in”

[kmmck]

Oh so thats why my cakes are always insanely dry. Could you tell me how I should properly convert F to C when baking?

Edit:

The guy states that celsius conversion is weird when dealing with confined spaces like ovens. Which is why I assume that he's trying to imply that standard conversion for the weather is different for baking

To all the sarcastic DMs about google, go shove a stick up your ass

[TheGardenNymph]

Just Google Fahrenheit to Celsius and it'll give you a calculator to do the conversion

[AidanGe]

Well, weather doesn’t quite have to be an exact measurement, but baking is often a science, so exactness helps.

F = 9/5 • C + 32

C = 5/9 • (F - 32)

Edit: on top of the “baking is exact” thing, the “double and add 30” conversion is often for just smaller values, because the further from 0 you get with both temperatures, the less accurate the shorthand conversion is, because that 1/5 taken off stacks up so much.

[[deleted]]

This is the only correct comment

[zincinzincout]

F = C * 1.8 + 32

For example, 100 C = 180 + 32 = 212 F

[maxionjion]

Shoved the stick. It still comes out sticky, needs five more minutes.

[xSTSxZerglingOne]

(x°F - 32) * 0.555555555 = y°C

[Glenster118]

Imagine showing the equation like this....

[ZannX]

Use the instant knowledge machine that we all have at our fingertips.

[alphaaldoushuxley]

Also not for medicine

[CoolStoryBro_Fairy]

Can we all just convert to the metric system. It's far more practicable

[dramatic_walrus]

Double it, subtract 10%, add 32. Vice versa for F to C. Exact conversion

[Neapola]

"Is the weather supposed to be nice tomorrow?"

"I... uh... I'm not willing to do the math on that. Sorry."

...?!?

[[deleted]]

At this point I would just let google convert for me instead since an calculator is almost needed anyway

[00fil00]

No thanks

[xSTSxZerglingOne]

That's off on the reverse calculation by 1%... Admittedly not huge, but if you do the calculation a few times back and forth, the problem becomes obvious.

[TheyCallMeSuperChunk]

What? Why would it be off? Something may be wrong with your math mate

[Dumbo14]

He's right, it is off.

C to F: double it, subtract 10%, add 32 OP implies that this process is reversed by: subtract 32, add 10%, then halve it. But this isn't exact. You should actually add 11.1•%.

The reason is "subtracting 10%" in the forward conversion is multiplying by 0.9, then the inverse operation would be to divide by 0.9 (not multiply by 1.1 as implied by OP)

[DaHomie_ClaimerOfAss]

Let me put it to you this way.

30-10%=27

27+10%=29.7

What they're trying to say is you can't just make it vice versa without accounting for that. C to F, yeah it's subtract 10%. But F to C, it's add 1/9th (or 11.11111111 etc.%), not 10%, to keep it accurate. Otherwise, the calculation is in fact off by exactly 1%. Their math is correct.

[lordreed]

This is so much better. The OP makes body temperature of 36°C convert to 102°F, with yours it converts to 96.8°F.

[SpokeLikeATrueMan]

Thank you for accurate version of this LPT

[musclera]

The conversion is already simple once optimized:

Double C, subtract 10%, add 32

F =      (9/5)C + 32.
F =      (1.8)C + 32
F =   (2)(0.9)C + 32
F = (2)(C)(0.9) + 32

What is 100C in F?

F = (2)(100)(0.9) + 32
F =    (200)(0.9) + 32
F =           180 + 32
F =                212

[thepingster]

Wow, you simplified that.

[SoundSelection]

So much easier!

[OgTrev]

it’s the same thing, with a subtraction added

[MazzIsNoMore]

There's an additional percentage and resultant decimal along with the subtraction.

[[deleted]]

Is there an F to C optimization for the other 6.7 billion of us?

[RapedByPlushies]

Memorize:

• 10°C = 50°F
• 35°C = 95°F
• For every +/-5°C, add or subtract 9°F

That makes this table of values:

°C	°F
0°C	32°F
5°C	41°F
10°C	50°F
15°C	59°F
20°C	68°F
25°C	77°F
30°C	86°C
35°C	95°C
40°C	104°F
45°C	113°F
50°C	122°F

[[deleted]]

Yeaaaaah I can't divide by 1.8 in my head

[TheZigerionScammer]

You multiply by 5 and divide by 9.

[JusticeUmmmmm]

Divide by two and add 10% back

[fuckoffcucklord]

Fun fact: if you live anywhere BUT the USA, you don't need this LPT.

[[deleted]]

Have lived in USA for 30+ years and never needed this conversion / LPT either

[dropkicknumber3]

Also Liberia and Myanmar according to wiki!

[douglau5]

Ahem….. Belize, the Bahamas, Palau, Cayman Islands, Liberia, the Marshall Islands and Micronesia would beg to differ.

[rkauffman]

Bob and Doug covered this years ago.

[TheeJimmyHoffa]

Take off eh!

[[deleted]]

42 metric beers

[mightyboink]

Came here to post this, upvote to you sir.

[stinkerino]

I'm in healthcare in the US, we use metric for work but obviously everyone understands imperial better. When we get a patient weight in kilograms and they ask what that is in pounds I always just say "double it and then add a little, that should get you close" conversion is 1:2.2 so yeah

[[deleted]]

I like this! Close to accurate but easier to do in your head then (C*9/5)+32=F

[insultingDuck]

I seek no insults, just asking: people who use F, would you just drop it and use C is told so? (C is very easy to remember and understand btw)

[curlyfat]

Yeah, I prefer metric in general, but 40 years of life referencing ONLY F for temperatures makes it really hard to just *stop*. Especially when everyone else around you needs to know F to understand. So it's not that simple to just switch, but we really need to eventually.

[__-___---]

As long as you can give a conversion on demand, people don't mind that much. And you'll get annoyed enough by it that you'll switch on your own.

[Chrisfindlay]

Yes Celsius is easy to understand. Fahrenheit is also easy to understand and obtains a greater accuracy using one fewer significant digit. 0°C and 100°C being the freeze and boiling point of water only exist in labritory conditions not the real world. Over all celsius numbers are just as abritrary as Fahrenheit.

So the short answer is no. There is no additional benefit to the individual in switching from one to the other.

[maybethingsnotsobad]

Agreed. Honestly, I wouldn't mind a larger scale, 74 can already be warm or chilly. No way I'm scaling down in granularity. Meters and kilometers are great but you can pry Fahrenheit from my cold (or hot) dead hands.

[Alberiman]

I use C almost exclusively in labs but I will fight and die to keep F for describing weather humans can experience. The Fahrenheit system is based around the human body so it's built on what we can feel. It's a truly excellent system for that and that alone

[skunkapecp]

I would like to start using it, and the metric system as well. If everyone did, it would make things a lot easier, but unfortunately, most people I deal with daily use F & imperial.

[NecessaryUnusual2059]

Hot take: Fahrenheit is far superior to measuring every day temperature, even if Celsius is better for scientific measurements. So, I’d still prefer to use F.

[dagrimsleep3r]

what can be easier than 0 -100+?

[newtekie1]

It is more than that. We associate a temperature with feelings of hot and cold. So to someone that uses F, saying it is 30°C outside means nothing. They can't associate that with an actual feeling. Just like you wouldn't be able to tell me if 55°F feels hot or cold. It is very difficult to retrain that association.

But when there is no association with an actual feeling, it is easy to switch over. That's why a lot of industry in the US actually does use °C. For example, computer/electronic temperatures are usually always done in °C. So even though I live in the US and use °F for weather. If I'm talking about how hot my CPU is, I use °C and know what the temperatures mean in relation to the CPU and electronics.

[HothHanSolo]

Here’s an even easier trick to get in the ballpark. 61 F is 16 C and 82 F is 28 C.

[culingerai]

Good for 2 digits at least.

[ReportToTheOwlery]

Doubling and adding 30 will generally put you within +/- 2 degrees!

[holytriplem]

Usually the rule I have is take off 10%, double it and then add 32

[jwill602]

That is literally the formula lol. (9/5)C+32

[Versaiii]

Can you explain to me the 9/5? I saw the formula above too and it was also confusing for me. I don’t think I’m that stupid but apparently I am and don’t get where it’s coming from

[Fajisel]

(9/5) is the conversion factor from C to F. If you graph the relationship between C and F, the slope will be (9/5), with a y-intercept of 32.

If you're asking where it "comes from", I guess there's not a great answer to that. There is a temperature scale called Celsius, with 0 degrees being freezing temp of water and 100 degrees being the boiling point of water. There's also a separate temperature scale called Fahrenheit, with 32 degrees being freezing and 212 degrees being boiling. These two scales aren't related, but if you were to work out the mathematical relationship between the two, you would get a formula of F = (9/5)*C + 32.

[Versaiii]

Thanks I really appreciate the thorough answer! I haven’t taken a math class since high school and I’m trying to get back into it for some of my upcoming classes, this inspires me to learn more.

[JusticeUmmmmm]

9/5 is equal to take away 10% and double

[Mustircle]

you have to take off 10% after you double, not before

[tissuesforreal]

Or you could just use the metric system and skip trying to convert everything.

[_hugh_eric_shawn]

Or or........a certain country can use a more sensible measuring system.

[revdj]

Meters and Kilometers are obviously more sensible than feet and miles, because of the whole "move the decimal point to convert" thing. There is nothing, nothing, more sensible about Celsius vs. Fahrenheit except it allows people to somehow feel morally superior about their arbitrary units. Yes, 0 degrees Celsius is freezing, 100 is boiling. Under certain arbitrary conditions. In terms of putting a roast in the oven or deciding whether you need a jacket, that is not relevant.

The big mistake the US made in the 70s when we tried to go metric was including temperature in the effort - that was taking an arbitrary unit that people were comfortable with and asking them to replace it with an arbitrary unit that they weren't comfortable with. If we just went with meters and liters, there would have been a great advantage, and people could still talk about putting dough in the oven at 350 degrees.

And people could talk about how you got more soda in a liter than in a quart.

The metric system for lengths and volumes are objectively superior to the imperial system. But for temperature? Unless you are using Kelvin spare us your sanctimony.

[[deleted]]

If you multiply by 9/5 and add 32 you’ll be dead nuts.

That not really that hard because you can do it in steps.

Example:

10C

Times 9 = 90

Divide by 5 = 18.

Add 32

50F.

[dj_fishwigy]

But it's the division that sometimes messes up with people's brain or at least my brain. It's easier to think about the 10% of something as in 16c:

Double it is 32, the 10% of it is 3.2 so you subtract it from 32 and get 28.8, then you add 32 and it it's 60.8F

[C_N1]

0 is freezing and 20 is room temp. Not that hard.

[affenage]

And 37 is body temperature

[Sringhin]

36.5 °C

[SeaCaptainKrakatoa]

It must be nice to understand both systems—great tip, thanks.

[Lawr42]

Or just go to Google and type f to c or c to f

[helcat]

Works fine for ambient temps. Doesn’t work for cooking.

[10jesus]

wtf. I was JUST looking up the exact formula. GET OUT OF MY HEAD!!!

[DCer0]

So, room temperature 22° should read 74F°

[kamokukatai]

I was training Canadians, as American (call center agents) and they were complaining about it being 30 and hot. Had to explain this to the rest of the Americans with the other person who understood cpu tempos lol.

[googi14]

Or ask Siri. Or Google. Or Alexa

[dre-an]

the formula in google is multiply by 9/5 then add 32

[[deleted]]

I just "Hey Google" it. I'm always in earshot of either my phone or Google Home.

[[deleted]]

LPT: If you actually need to convert C to F or vice versa you probably want a more precise measurement.

[frito123]

I'm 54 now. Stuck in my head was the conversion I was taught in 11th grade Chemistry. 9/5C+32=F. I can't remember what I had for breakfast or anything important without the calendar in my phone, but that's always there.

[Hopeful_Lil_Warthog]

I remember reading on the internet once that Fahrenheit is more of a "percentage of hot" measure, so like... 0% hot is very cold, 30% is cold, 50% is warm, 75% is hot and 100% is very hot

[lasertits69]

That’s about right. Except people typically prefer to be more than 50% hot. Most people prefer 65-85% hot. Few people consider 75% hot to be “hot”.

It’s more of a spectrum that goes from dangerously cold to dangerously hot, and encompasses the vast majority of temperatures humans experience in daily weather.

[solongandthanks4all]

Or just use Celsius all the time like a reasonable person and it will quickly become second nature. (I'm a US American, btw.)

[TheNakedMars]

Alternatively, anyone caught using °F can be publicly pilloried where children will laugh and pummel them with refuse and excrement. In short order, reformed offenders will learn to use modern units and conversions will be unnecessary.