What exactly is the difference? I am confused in regard to "version" of Gokyo Shumyo. http://senseis.xmp.net/?GokyoShumyo

Hashimoto and Go Seigen have different version of Gokyo, meaning their versions aren't as intended by the original author? (the problems only not the answer)

What about other classics treatment?

Usually the original version are presented with very short answers with few variations. The later editions from people such as Hashimoto and Go Seigen are usually their explanations of the problems from the classics. There will usually be an expanded explanation or even a better revised answer. Furthermore there may even be revised problems for those which after careful analysis are shown to be failed problems as presented in the original. I have encountered some revised problems when I looked at some of the tsumego from Shiqinglu (適情録) which were explained by Go Seigen in his supplementary explanation volumes. There are currently no easily accessible English translations of Shiqinglu which I know of.

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