> the 19th century actually refers to the 1800s

Also, this isn't strictly accurate: the 19th century excludes 1800 but includes 1900.

Personally I love it when people do this. It's just.. it saves me the few seconds it takes, every time, to subtract "1" from the number.

It's not that hard with "20th century" which I'm conditioned to map to "last century" immediately, but when someone did something in the 17th century I first think "Oh like 1750-ish" and then I realize I'm a century off, and it disrupts my reading flow.

I find it remarkable that it's that hard for you.

They do not say it was hard. There is a difference between being hard and requiring 0.5 second more of thinking, which can and does disrupt the reading flow.

Exactly this. I actually think it’s exactly the opposite of assuming your audience is a stupid: it’s respecting them enough to do the work yourself instead of offloading to them. I’ll die on the hill that 19th century referring to the 1800s is fundamentally unintuitive.

It shouldn't take 0.5 seconds of thinking, unless you're a total historical illiterate.

You're not arguing in good faith here. Which is fine, but then please stop insulting others.

> Way to assume your audience are morons.

Is there really much benefit in framing it this way?

I see the phrasing decision as raising several questions for the author:

1) Who is your audience?

2) What are your goals for the communication?

I could imagine either phrasing choice making sense depending on the answers.

On the internet, best growth strategy is to assume your audience are morons.

No, it's worse than that.

"The 1800s" typically refers to the years 1800-1809. "The 1900s" refers to 1900-1909. It is by no means unambiguous, but this is the common and plain meaning, and indeed these folks may confuse many more people by attempting in this manner to refer to 1800-1899 or such.

I disagree. When people typically pronounce, for example, "1800s," they would say "Eighteen Hundreds," with the plural suffixing "hundred," implying a period of far longer than a decade. If trying to reference the decade following 1800, in conversation I would say "the Eighteen Noughts."

I don't know what sort of localized English you speak, but that is not how it works in America. [Based on past comments, you may be located in Australia. I could certainly understand if there are local phenomena in your language there.]

If we say "In the nineteen hundreds..." we mean 1900-1910. If we said "In the ninteen fifties" we would not be implying a 50-year period, would we? If we said "In the nineteen nineties" are we implying a 90-year period? Do you see how your logic immediately breaks down? Is it mere accident that "the ninteen tens" is a ten-year period of time? Yes it is...

Your assertions and these patterns of speech are just bizarre. I don't know anyone who says, or writes, "the Eighteen Noughts" at all. It is not a thing for scholars of history, for sure.

For a while it has been debated how we'll refer to 2000-2009. Because in different centuries, those initial ten years gained unique names. Some people want to call it "The Aughts" or "The Noughts" but I don't really hear people referring to "The Two Thousands" yet, at all; it's largely "The 21st Century".