AAAAtoms

So humans feel cold at 0F and hot at 100F?

In aggregate this is absolutely true, though not the point anyone is making.

Humans start quickly dying at something around 32F and 180F

Humans will die of dehydration or heat stroke quite quickly at temperatures well below 180F. In fact that's far hotter than the hottest recorded temp on Earth (~135F/56.7C) (not including human-made environs like a sauna or outliers like an active volcano) so I'm frankly not sure what point your even trying to make here.

Fahrenheit is complete nonsense. It has nothing to do with humans.

The latter statement is manifestly false. Fahrenheit was originally supposed to have 90 degrees as the average humans body temp (no clue why 90 and not 100). Due to inaccuracies in measurements of the time, It was later changed to 96 and then 98.7. Still no clue why not just 100, but the fact remains it was based on human body temps. The zero point was selected using the freezing point of a brine mixture. No real defending that one, it was pretty much arbitrary.

And considering humans are mostly water Celsius seems a much better fit.

But we aren't just water. In any case, humans are rarely at boiling temperature. My ideal temp scale would have 0 at water's freezing point and 100 at a humans body temp.

I don't think I can tell the difference if something is only one degree apart in Celcius, let alone Fahrenheit.

Comparing an 18C day to a 19C day, for example, I challenge anyone to notice a difference. A 64F to 65F day? Good luck.

I agree with the Celsius scale making sense around zero. Water freezing is probably one of the most relatable, quantifiable examples of a temperature point for the most humans. However, lots of people don't live somewhere that it snows, or even own a freezer.

So what's the most common touch point for people? I'd go with water boiling. I can't really think of what sort of person who did not have exposure to that at some point. That should be the zero point, the common denominator.

Yeah, no, that's not helpful at all - what I consider cold and what my mum considers cold are very different temperatures, and what I consider hot and my neighbour considers hot has an even bigger difference.
You rationalise it with the "human scale" idea, but really you just know the range of temperatures you're personally comfortable in, just like everyone using Celsius does.

Then 50 is the optimal temperature right?

With 80 being as uncomfortable as 20

What's not to get lol. Think about when it's really really cold outside. That's 0. Think about when it's really really hot outside. That's 100.

Nah it's more like, one degree fahrenheit is the smallest change in temp that the average human can sense.

When it's above 100, people who have options for something lower will generally go for them. Similarly for under 0. OK, so as PancakeLegend@mander.xyz pointed out, such sensitivities might be specific to US culture, but theoretically, how much would we have to expand the 0-100 Fahrenheit range so that 0 is too cold for pretty much everyone and 100 is too hot for pretty much everyone? 0 goes to -10, 100 to 140? A new-Fahrenheit degree would still be more precise than a Celsius degree.

Fahrenheit was not an entirely arbitrary choice

it's not arbitrary, it's based on the uh, the freezing temperature of uh, ammonium chloride! we're all familiar with how cold that is! and, and, and, uh, the upper end is, uh ... they decided on 96. it's not arbitrary!!!

...96? How is 96 a point of reference when you are making a scale from scratch?

Yeah after I discovered that sort of meaning for fahrenheit, it made a lot more sense to me. So no issues with fahrenheit, but imperial is still crazy to me

Farenheit is asking Americans how hot they feel.