There is much that I would like to quote from Andrew Marr's book, but in order not to disturb his publisher, I'll restrict myself to:
"Transcendence is what we hope for from art whether it be through the slow movement of a Beethoven string quartet, a soliloquy in a Samuel Beckett play, or the shapes and colours of a late Matisse … Successful art engages the intellect as well as emotion. It makes us concentrate. It quickens our breathing. It sharpens our attention. It cleans our spectacles … "
The above quotations are from Marr's first chapter. They state a coherent philosophy with which I agree, and set the stage for Marr's main offering: a guided tour of the way an artist thinks and works. Whatever one thinks of his paintings (he is quite self-deprecating) one can learn much about the art of painting just by listening to him relate what he considers to be his failures, his attempts to rectify failures, and the unexpected path that he has sometimes taken to succeed with a painting.
Our concern here is with music, so I won't delve further into Marr's book, but I do recommend it. Don't be put off thinking "oh, he's a broadcaster who paints for a hobby". He has devoted himself seriously to painting since a near-fatal stroke made him aware that (as he writes in his first sentence) "our time in this world is very beautiful, and very brief".