"To speak of these things and to try to understand their nature and, having understood it, to try slowly and humbly and constantly to express, to press out again, from the gross earth or what it brings forth, from sound and shape and colour which are the prison gates of our soul, an image of the beauty we have come to understand - that is art."

I like this quote most of all, as it expresses Joyce's idea that the senses are the prison gates of the soul. Art must use the senses as ways out, but we must understand that beauty resides beyond them.