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by al_borland 1 day ago
This has always been my primary argument in favor of Fahrenheit. It makes sense for humans, which is all a majority of the population really cares about. In addition, it's more granular. Sometimes turning the thermostat up or down by 1C could be too much, where 1F is just right.

In science and math, I can see where having round numbers for commonly used temperatures would be useful, but if 0C and 100C are the only places that happens, it's not that hard to memorize 2 numbers.

4 comments

You only think it makes sense for humans because it makes sense for you, where you live the same way you feel changing a thermostat by 1F is perfect but 1C is too much: that’s true for you, not universally.

Fahrenheit functionally requires you to be biased in order for it to seem like a good system.

It provides greater granularity in the range of human comfort, without descending into decimals. How is that not more useful for day-to-day human usage?

0F is cold, 100F is hot. I experience both of these temperatures outside where I live every year.

-20C to 40C seems much more arbitrary as a way to measure the zone humans mostly live in.

I would wager that the outdoor and room temperature are an overwhelming majority of human use for temperature. It seems like it would make sense to optimize for how temperature is more commonly used at a population level.

I would say those who see Celsius as a good system are also biased, because they grew up with it and it’s what they’re used to.

> 0F is cold, 100F is hot. I experience both of these temperatures outside where I live every year.

This is just your location, and things like this vary around the world a lot. Hell, they vary in the US. To me, where I live (in the US), 0F and 100F aren't really useful as benchmarks; we don't see either of those temperatures here, ever. The normal range is more like 40F-80F (with extremes maybe down to 25F and up to 90F, but those numbers push credibility a bit).

But ok let's look at averages. Do "most humans" (whatever that means) really live within 0F to 100F? That doesn't really pass the smell test for me; there are lots of humans who live in places where it regularly exceeds 100F. And in those places I doubt it gets anywhere near 0F, with many places never getting down to even 20F. There are also lots of places that get warm, but will never see 100F, and seldom see 90F.

It's all super super arbitrary.

Having said that, I still prefer F over C, but I don't pretend there's any rational reason for it: it's just because I grew up with Fahrenheit, and no matter how hard I try, I just can't feel Celsius the same way. I feel like you maybe don't interact with too many people who grew up with Celsius; you'd probably realize they feel the same way about C as you do about F, and that there's no rational reason for it. It's just what you were trained to think and feel in, and it stuck.

> 0F is cold, 100F is hot. I experience both of these temperatures outside where I live every year.

Most people never experience anywhere near 0F in their lives.

> -20C to -40C seems much more arbitrary as a way to measure the zone humans mostly live in.

The zone most humans live in does not routinely (if ever) get anywhere near -20, to say nothing of -40.

I experienced 3°F in the subtropics and it is probably about 100°F outside right now. Average winter temps of 35° with only 1-7 days of actual frost, usually around christmas. (Dec 25(December 25))
The -40C was a typo, should have been 40C, to mirror the 0F to 100F, rounding a bit to make it less silly. It’s been fixed now.

Millions do experience 0F, and it’s ok to not use the full range. At or around 0F is cold, as you move closer or beyond it, it’s cold. As you move closer to or beyond 100F, it’s hot. Most people would likely prefer to never deal with <0F or >100F.

Millions -- hundreds of millions, even -- regularly experience -10F and 110F as well, but you've arbitrarily picked 0F-100F, so I guess their experience doesn't matter, because you prefer round numbers?
> Millions do experience 0F, and it’s ok to not use the full range.

That’s not even an argument. Billions never experience freezing temperatures let alone 0F, and it’s ok to use negative numbers.

> At or around 0F is cold, as you move closer or beyond it, it’s cold.

The exact same statement can be made about 0C. Hell if you live in a subtropical area 10C is cold.

> Most people would likely prefer to never deal with <0F or >100F.

Most people would likely prefer to never deal with < 15C or > 30C.

Human body temp is nearly 100°F and a freezer routinely is around 0°F.

Can we stop arguing now?

> you feel changing a thermostat by 1F is perfect but 1C is too much: that’s true for you, not universally.

I've noticed that here in Japan all the AC units seem to be adjusted by half a degree Celsius at a time, so I do think 1C is a bit much even for people who never used fahrenheit.

The good thing is that there is nothing preventing anyone from adjusting their thermostat with a decikelvin precision. Or hell, even centikelvin if they’re pushing it.
Actually, 1 degree of Fahrenheit is the amount of temperature change a typical human can connect. It's a human-calibrated scale.

Though why 32F instead of 0F for frozen water...I have no idea.

> 1 degree of Fahrenheit is the amount of temperature change a typical human can connect

Citation needed. https://en.wikipedia.org/wiki/Fahrenheit suggests no such thing, nor have I ever heard the notion.

Because lower point is temperature of certain chemical reaction. And upper end is body temperature... Oh wait... Yeah it is bad scale.
Every non-US thermostat I've seen that works in Celsius is adjustable by half-degrees, so it seems the manufacturers agree with my feeling there...
Living in Australia and India, I have never encountered such a thermostat. But I do vaguely recall encountering a thermostat somewhere at some point that went up by twos in Fahrenheit.

I would guess you would only encounter ½°C steps on units that support both Celsius and Fahrenheit, so that they’re closer to parity. I don’t think any unit that I’ve owned has supported Fahrenheit at all.

I can't express just how profoundly culturally biased this is. There is absolutely nothing about Fahrenheit that 'just makes sense' to someone who grew up with Celsius instead.

Your comment about granularity is also nonsensical. I can adjust my heating by more granularity than 1C. That has literally nothing to do with the units being used.

As someone who has used Celsius all my life, I actually kinda think they have a point here - where I live temperatures range from -10 to 39 in Celsius, and our home thermostats have 0.5 degree increments. Had we used Fahrenheit it would be a more human-friendly and compact-display-friendly 11-99 with little need for the fractional part.

-10.5 = 5 characters 11 = 2 characters

Celcius is pretty intuitive actually. It takes atmospheric pressure into account, Water is pretty abundant on the surface of the planet, and life kinda depends on it. It's a remarkable substance and quite stable. I dont think theres another substance where we can see all three phases with kitchen appliances and still consume it. Equally good for bathing and drinking. I need steam to clean clothes and cook my food. Using water as a benchmark for how we measure temperature is remarkably useful.
With all of those examples, the actual temperature doesn’t really matter.

For drinking and bathing, people go by feel. In the kitchen, the freezer makes water freeze, and the stovetop will make it boil into steam, but exact temperatures aren’t really relevant here either. The same goes for ironing clothes, the iron just does it.

When I think about where explicit temperatures are needed in the home, the oven and thermostat are the two things that come to mind. Water is pretty irrelevant for both of those. For cooking or frying someone may monitor meat or oil temps, but those aren’t water. A hot tub might have an actual temp on it, but those tend to be around 100F, not 100C, as they are meant for humans, not boiling.

Water is an amazing liquid, but I still struggle to see how measuring all our temperatures based on it makes sense.

> For drinking and bathing, people go by feel.

Yes, and people who grew up with Celsius feel in Celsius, and people who grew up with Fahrenheit (like myself) feel in Fahrenheit.

Stop trying to make some sort of determination of what's logical or reasonable here. Neither one is more or less logical than the other for day-to-day layperson use; anyone can "feel best" in any scale if they were taught it at a young age and used solely that scale for the formative years of their lives. Hell, I bet you could make a kid feel in Kelvin if that's all they were exposed to for their childhood. Or in some made-up scale that takes your 0F-100F and compresses it inside 22-35.

When I said drinking and bathing go by feel, I meant that they aren’t measuring the temperature, so the units are irrelevant.

When drawing a bath, I don’t get out a thermometer, I just stick my hand in the water and feel if it’s comfortable. C, F, or K… who cares? It doesn’t come into play.

> When I think about where explicit temperatures are needed in the home, the oven and thermostat are the two things that come to mind.

But in that case in what way is for example baking a frozen pizza from the store at 400 to 425 degrees F more relatable/convenient/natural than 200 to 220 degrees C?

It's not. When it comes to an oven, F and C are equally arbitrary, so it really doesn't matter. Optimize for what people use most, and let the other random uses fall as they may.
You have it backward. There's no absolute truth on what's optimal for what people use most. What's optimal is just what you were reinforcement-trained to feel when you were growing up as a child. That's it.

My wife says "30C" and knows exactly how that feels, while I struggle to find a reference point. I say "86F" and know exactly how that feels. Even though she prefers C, she can feel F slightly better than I feel C, as she moved to the US when she was in her teens. (Whereas I've spent my entire life in the US, outside of business and holiday travel.)

> It makes sense for humans, which is all a majority of the population really cares about.

The Celsius scale makes perfect sense to me and the vast majority of humans in the world. Much more so than the Fahrenheit scale, which I absolutely never use. That’s not really a strong argument.