Lots of nice quotes here. :)
Because of how my memory works, I only have a few favourite quotes that I can bring up spontaneously and which are worthy of deep thought, most quotes I remember well are simply on the "amusing" or "funny" categories; however, here's something I liked very much from a work I read only recently:
"The receptivity of the artist must never be confused with passivity. Receptivity is the artist's holding him/herself alive and open to hear what being may speak. (...) It is a waiting for the birthing process to begin to move in its own organic time. It is necessary that the artist have this sense of timing, that he or she respect these periods of receptivity as part of the mystery of creativity and creation." - Slight paraphrase from The Courage to Create, Rollo May