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by typewithrhythm 450 days ago
Humans cannot reliably determine the difference in one degree c, even though it's bigger... Fahrenheit is too fine grained, and has no interesting points relative to the things I interact with. I freeze an boil water often, however
3 comments

The base units of the metric system are often not very ergonomic. Why is a meter so damn big? And why is a gram so damn small? I can barely detect a gram. And a meter is frickin huge, causing people to usually divide it into hundredths of a meter, which you can hardly picture in your mind unless you already know what it looks like, especially arbitrary counts of cm. Metric's only real advantage is that it shares the same radix as our counting system.

What we really need is a new system of units...

Using metric has never been an issue in trades or sciences in metric countries.

A metre is much the same as a yard or an adult arm span. Not a problem.

Pretty much all carpentry and cabinet making is done in mm alone, the width of a fat pencil mark.

1400mm is shy of a metre and a half (1500mm), cross piece spacing might be 300mm (about a foot).

No need to have feet, inches, quarters and thirds mixing up the page, just use mm everywhere.

A gram is fine for small mass measurements, a kilogram is a good unit for heavier masses - very human scale being the same as a litre of water and more or less a litre of milk.

It really comes down to familiarity, there's nothing intrinsically difficult about metric (and much that is more intuitive than odd imperialial units and the whacky intra unit conversion factors).

As a metric user, this is an interesting point that I haven’t heard before, and I think the other responses don’t really engage with it. Yes, familiarity means this isn’t much of a daily problem – you just use divisions of the unit that are most appropriate. But the size of the base units for volume, mass and length don’t really match up well from a human day-to-day perspective.

Wouldn’t it be nicer if a litre, a gram and a cubic metre of water were equal, rather than 1 cubic metre, 1000 litres, 1,000,000 grams?

Side note that in Europe drinking products are often labelled in centilitres whereas Australians use millilitres. I wonder whether this indicates some difference in the way the two groups think about volume, or maybe it is just the fallout of some other constraint, like translations limiting the space available.

Still, the ergonomics seem to be on the side of Metric, taking into account the ease of conversion between units when all are base ten.

As a metric user: This is about your lack of familiarity.

E.g. can picture lumber expressed in cm or mm very easily. E.g., if you work with beams that are 48mm / 5 cm or 98mm / 10cm a lot then those sizes becomes second nature. Just as easy to picture as 2 inch, 4 inch, 1/2 inch, 3/4 inch etc that is in use in US.

And saying that something is 200m away is exactly as intuitive as however many feet that is. A large meter has a usecase.

I feel square metres for houses is very natural unit and square feet sounds awkward (each patch of house area is so small you can do nothing with it, a square metre gets you somewhere..).

Making yet another system of units sounds like massive pain and as someone who are used to metric I see no advantages.

As a user of both Imperial and Standard International units, I agree with you.

As a kid, one of my science educators spoke about the many benefits people gain from becoming familiar with basic units. I bought in and did so during the big metric push that happened around that time.

I ended up more familiar with Imperial units.

Then, later in life, I entered a young industry, with strong users of metric, Standard International units.

So I did the work to build familiarity just as I did long ago. Took half a year and today I enjoy the benefits.

And those are:

Ease of understanding unit values meaning in my daily life.

Ease of expression of same to others.

Greater accuracy estimating.

Easier computation and unit checks.

And so on...

Ah but are 48x98s nowhere near 48mm and 98mms like our 2x4s?
48x98 is exactly that dimension (i..e after planing of the lumber). Well, +/- 1 mm of tolerance/shrinkage due to drying.

It goes by the name "two four" here as well informally due to long tradition (and yes, I once did wonder why 2-by-4 is smaller than 2 by 4 inches and looked it up), but you will not see it written anywhere, in writing it is always in mm after planing.

The oral words for lumber dimensions before planing is the only context as an adult I have met inches except in US.

I grew up during the F to C transition in the UK and F is not intuitive.

0 = ice 100 = steam

That is pretty intuitive if you ask me. And for gravy comfortable room temp is about 25

Fahrenheit is sort of intuitive if you think of it as somehow, impossibly, a percentage scale. 0C/32F is still decently comfortable anyway. 0F is, like, not at all comfortable. 100C is dead. 100F is the most unbearably hot temperature that isn’t immediately deadly.
Fahrenheit is very intuitive if you are in Danzig in one particular year... [0] otherwise.. It's a historic accident. If you want to root your measurement system in human experience your measurement system will be outdated in a couple of decades. Because humanity changes! That way there will always be old/antiquated/historic units. Metric basically accepts that and uses easy to convert units and leaves the intuition forming to the humans gathering the experience

[0] Apparently the story is disputed.. But the way I was taught it was: 100F == typical healthy human and 0 F == lowest temperature in Danzig in the winter 1708/1709. This makes it (by construction) a more natural fit to human experience (especially one in northern Europe) https://web.archive.org/web/20131015045624/http://www.deutsc...

It's missing one important distinction: Below 0C: Freezing, probably slippery, not raining water. Above 0C: not freezing, probably not slippery, rain comes as water. They are as uncomfortable as you make them.
Our maximum day time tempreture in January 2025 was 113 F ( 45 C ), 12 days or so were over 100 F ( 37.7 C )

http://www.bom.gov.au/climate/dwo/202501/html/IDCJDW6136.202...

This is in the cooler south west corner of a large state ( 3x size of Texas )

Of course, the experience of heat does depend on humidity as well. But, how was it? It sounds… too hot!
100°C is somewhat uncomfortable, and it usually indicates that someone is trying to show off. 80 to 90 is much better. (In a sauna.)
Just curious on what planet you exist where 100C is only “somewhat uncomfortable”
It does kinda depend on humidity, fwiw. In New England, the 90’s are hot, unpleasant sticky weather.

I guess it doesn’t happen often, but I saw some upper-90’s temperature in the Portland, Oregon area. It feels relatively mild actually, compared to New England 90’s, I’m pretty sure because it is so dry. The lighter air just carries the heat away, rather than having it stick to you.

I think GP was talking about saunas and not ambient temperature. So 100C not 100F. Still the argument remains the same: Low humidity (and reasonably short durations)
This is false. I frequently find myself annoyed at my AC because it only has settings of 72°F and 74°F, and they are a little too cold and a little too warm for me. I want 73°F. When it's around room temperature, you can absolutely tell the difference.

The further away from room temperature, the less we can distinguish. All our senses work logarithmically like that.