What do you know of the mystery schools?

The schools that Jesus, Beethoven, Mozart, Bach, Michealangelo, Da Vinci and many other geniuses from our past attended. I'm not saying they went to the same schools, but they were all a part of secret societys that taught the Occult knowledge. Can anyone tell me something I don't already know? I'm not saying that I know everything, in fact, the more I learn the more I realize that I don't know much. I'm just looking for other intellegent beings. I might be wasting my time, but everything happens for a reason.