Did you know that the english word “star” and the japanese word 星(ほし)don’t actually mean the same thing?
Language does not simply name pre-existing categories; categories do not exist in 'the world'
— Daniel Chandler, Semiotics for Beginners
I read this quote a few years ago, but I don’t think I truly understood it until one day, when I was looking at the wikipedia article for “star” and I thought to check the Japanese article, see if I could get some Japanese reading practice in. I was surprised to find that the article was not titled 「星」, but 「恒星」, a word I’d never seen before. I’d always learnt that 星 was the direct translation for “star” (I knew the japanese also contained meanings the english didn’t, like “dot” or “bullseye”, but I thought these were just auxiliary definitions in addition to the direct translation of “star” as in "a celestial body made of hydrogen and helium plasma").
To try and clear things up for myself, I searched japanese wikipedia for 星. It was a disambiguation page, with the main links pointing to the articles for 天体 (astronomical object) and スター(記号)(star symbol). There was no article just called 「星」.
It’s an easy difference to miss, because in everyday conversation, 星 and star are equivalent. They both describe the shining lights in the night sky. They both describe this symbol: ★. They even both describe those enormous celestial objects made of plasma.
But they are different - different enough to not share a wikipedia article. 星 is used to describe any kind of celestial body, especially if it appears shiny and bright in the night sky. “Star” can be used this way too (like Venus being called the “morning star”), but it’s generally considered inaccurate to use the word like this, whereas there is no such inaccuracy with 星. You can say “oh that’s not actually a star, it’s a planet”, but you CAN’T say 「実はそれは星ではなく惑星だよ」 (TL: that’s not actually a hoshi, it’s a planet). A planet IS a 星.
星 is a very common word, essentially equivalent to “star”, but its meaning is closer to “celestial body”. I haven’t looked into the etymology/history but it’s almost like both english and japanese started out with a simple, common word for the lights in the sky - star/星 , but as we found out more about what these lights actually were, english doubled down on using the common word for the specific scientific concept, while japanese kept the common word generic and instead came up with a new word for the more specific concept. If this is actually what happened, I’d guess that kanji probably had something to do with it - 星 as a component kanji exists inside the word for planet, 惑星, and in the word for comet, 彗星, and in the scientific word for “star”, 恒星, so it makes sense that it would indicate a more general concept when used standalone.
This discovery helped me understand that quote - categories don’t exist in the world, we are the ones who create them. I thought that the concept of “star” was something that would be consistent across all languages, but it’s not, because the concept of “star” is not pre-existing. Each language had to decide how to name each of those similar star-like concepts (the ★ symbol, hot balls of gas, twinkling lights in the sky, planets, comets, etc), and obviously not every language is going to group those concepts under the same words with the same nuance.
Knowing this, one might be tempted to say that 恒星(こうせい) is the direct translation for “star”. But this isn’t true either. In most of the contexts that the word “star” is used in english, the equivalent japanese will be simply 星. Despite the meanings not lining up exactly, 星 will still be the best translation for “star” most of the time. This is the art of translation - knowing when the particulars are less important than the vibe or feel of a word. For any word, there will never be an exact perfect translation with all the same nuances and meanings. Translation is about finding the best solution to an unsolvable problem. That's why I love it.