Write . . . What You KNOW???

.Over on Facebook, Jeff Ford posted:

I see a lot of advice on the internet from writers and others based around the question as to whether to "Write what you know" or not. Some people get really adamant about this stuff. LOL! The message should be "Write whatever the fuck you want."

To which Kit Reed amplified:

I add:  I don't know what I know until I start writing it.

Both of which are good and wise observations.  But that original bit of hectoring advice... Everbody knows of it.  But how many of us know who originally said it?
I do.  And I'll tell you tomorrow.  See if you can guess.
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