I think the idea that you know who your inner self is on a daily basis because... you know. What's good for you 25 years ago may not be good for you now. So to keep in touch with that I think that's the first ingredient for success. Because if you're a successful human being everything else is gravy I think.
At the moment I'm doing this space movie so I'm obsessed with physics and space travel. I know three months down the line it's gone. Then I'll be able to superficially say stuff about space.