What should I ask Rick Rubin?

I will be doing a Conversation with him, here is Wikipedia:

Frederick Jay Rubin is an American record producer. He is the co-founder (alongside Russell Simmons) of Def Jam Recordings, founder of American Recordings, and former co-president of Columbia Records.

Rubin helped popularise hip hop by producing records for acts such as the Beastie Boys, Geto Boys, Run-DMC, Public Enemy, and LL Cool J. He has also produced hit records for acts from a variety of other genres, predominantly heavy metal (Danzig, System of a Down, Metallica, and Slayer), alternative rock (The Cult, Red Hot Chili Peppers, The Strokes, and Weezer), and country (Johnny Cash and The Chicks).

In 2007, Rubin was called “the most important producer of the last 20 years” by MTV and was named on Time‘s list of the “100 Most Influential People in the World“.

So what should I ask?

And I am excited for his new book The Creative Act: A Way of Being.