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in reply to Re: I blog...
in thread I blog...

You may mean: "Better to keep your mount shut and appear stupid than to open it and remove all doubt".
Attributed to Mark Twain (or whatever he was calling himself), in "The Sayings of Mark Twain", James Munson. May be apocryphal.
From a real paper book (!): The Oxford Dictionary of Humorous Quotations, by Ned Sherrin.
I'll shut-up now.