Art before realtiy -- The Great and Secret Show
Gregory Alan Bolcer stashed this in Creation
The original book about big data. Randolph is the main character who works in a dead letter office for the US Post office in 1969 when he starts reading the material.
The idea that there's some great secret in the data that we're not even looking at has been a cornerstone of big data systems everywhere. So much so that the concept was explored in fiction 20 years before it's being explored in science.