From Scorsese's doc on Dylan:

Dylan is quoting Liam Clancy, whom he knew in the early Greenwich Village days, and who was one of the big deals when Bob landed on the folk scene. He even does his Irish lilt. It's a great quote, and obviously meant a lot to Bob, but if I break it down I know I don't do any of it. Of the three, fear has been the biggest constant in my life. Envy was big, too, in my younger days, particularly when it came to writing and success, though there's way less of it now. I'll cut myself that slack. Meanwhile, I don't think I had meanness at all when I was younger but life changes you. I've had moments in my adult years. Not just anger but meanness. But again, cutting myself some slack, it's a rarity. If I had to compare myself to the whole of humanity, and why not, I'd say I've been more fearful, a little less envious and way less mean.

Anyway it's something to aspire to.