The quote from page 321 is correct, either with the "so" or without - using "so" would require swapping 'not' and 'to' in the sentence (as for "either", it can be used preceding a list but most commonly is not, so lots of people think it sounds funny when it is. I do believe a semi-colon would help, though, before the third item.)When talking about the Master, I think using "not" would be the right way to go. Using "non-" is technically correct, but very clunky before punctuation. Which should also be a colon.
As for Rithmatics, we don't know everything about it yet, so it's probably best to avoid the topic.