I'm glad the Frank Viola quote is in there, because I would have recommended it if it wasn't. I have found his *experienced*explanation to be one of the best/easiest to present for people to understand.
But in a sense, you could answer your friend's…
How difficult is letting our "yes" be "yes" and our "no" - "no" ? Very difficult today. Authenticity is simple but very rigorous. Breaking it down, it involves the putting aside of self and the fear of what others may think about us (me). Sounds lik…