Horibe wrote:...
Clearly outside of Go, Chinese is the most useful.
On a practical level, for go study, am I correct that Korean might be the easiest, particularly to read?
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People learn in different ways, so I think it is difficult to say that one language is "harder" than another. There's also the point that learning any language can be a continuous process. Even when you have achieved "fluency", there's a good chance that there are still new vocabulary or slang words to learn. For example, English is my native language, but I'd still say that there's room for me to learn more English.
That said, I will give my opinion, based on how I learn.
In my opinion, if you are going to learn any of the three languages seriously, learning Chinese characters is helpful. Even in Korean, where Chinese characters are typically not used anymore, many words are based on Chinese characters.
In that regard, I think that Japanese is a little bit easier in terms of reading, because the Chinese characters are clearly visible. If I see a particular character, there is no guessing what the meaning is. The character is plainly visible.
With Korean, on the other hand, Hangeul is very easy to learn, but it is a purely phonetic alphabet. This means that, while many words are based on Chinese characters, the actual Chinese characters are hidden from view. The result, to me, is a language that is easier to read phonetically, but harder to extract meaning from.
Chinese characters are extremely helpful in the three languages, and these characters are visible in Chinese and Japanese. Because of that, Korean can be a little bit more difficult to get meaning from.
In addition, I think that the actual sounds that are used in Japanese are easier to distinguish, typically. With the exception of the "n" sound, everything ends in a vowel sound, so it is a bit easier to pick out what people are saying. In Korean, combinations of the batchim and the next hangeul character sometimes lead to pronunciations that are non-intuitive to me. This may be due to the way that I learned hangeul in the first place.
But in any case, I think that people learn in different ways. For me, I think that Korean is a bit harder than Japanese in several regards. This could also be due to the fact that I lived in Japan for a longer period of time, though.
In the end, again, pick the language that's interesting to you.
I will agree with Horibe's point that, disregarding go, Chinese might be the most practically useful. After all, there are a LOT of Chinese people in the world.