Jon sez

The word "oracle" was first appropriated into SF (as far as I know) in Vernor Vinge's A Fire Upon the Deep to mean a hyperintelligent AI that would answer questions from the public (broadly construed). When I needed a term for Franklin turning his entire intellect on one question, my thesaurus-dive turned up the word "oracle," which I immediately set upon as the perfect word. Then I remembered Vinge and felt bad. Then I realized that Vinge wouldn't sue, so I went ahead and did it anyway.