The only reason Mormons believe it's the Holy Ghost is because they've been TOLD it's the Holy Ghost.
Take the Moroni challenge, for example. You're suppose to read the BofM and if you do it with a sincere heart, with real intent, blah, blah, blah, then the Holy Ghost will manifest the truth, blah, blah, blah.
So right from the get go, you're told if you get any good feeling it's the Holy
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