Oh ho ho, please let it be true...
From the Chicago Reader:
When I began looking for the original source of the Emerson line about “the secret” being the answer to everything, I expected to discover it as easily as I had tracked down the Churchill. But Google merely turned up Web sites that had culled the quote from Byrne’s book, and as within The Secret itself, these sites gave no indication of the quote’s source beyond attributing it to Emerson. When I searched electronic versions of Emerson’s complete works for every appearance of secret, I discovered nothing even remotely suggestive of the line Byrne credits to him.
Heh heh heh.