I asked this before, and the answer I got back was split into three main suggestions along a clear continuum:
The Sequences
Hayakawa's Language in Thought and Action
Korzybski's Science and Sanity
I've only read the first two. Apparently there is no substitute for reading Science and Sanity if you want to get everything out of Korzybski; people like Hayakawa can take out an insight or two and make them more beginner-friendly, but not the entire structure simultaneously. The Sequences apparently has many of the same insights, but arranged differently / not completely the same, and of the people who went through the trouble of reading both, at least one thinks it may not be necessary for LWers and at least one thinks there's still value there.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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