Nick Milton mentioned an old saying from the Middle East, and I had to go find the source. Turns out it comes from Ibn Shihab, an early Islamic scholar:
"Knowledge is a treasure chest and its keys are questioning." -Ibn Shihab
I like the sentiment here. You can't just put knowledge somewhere (knowledge repositories anyone?) and expect it to be useful. People learn through asking questions and a back-and-forth process with others.
[Thanks to Boris Jaeger (and Twitter) for helping with the sleuthing on the source!]