One of the best movies about art ever made, `The Horse's Mouth' examines the relationships between vision and creation, between art and commerce, and most importantly between art and criticism; and makes us laugh at the same time. Alec Guinness is inspired (when was he ever not inspired, come to think of it) as Gully Jimson, a painter of unlimited ideas who has met with only limited success in the art marketplace partly because he is so contemptuous of that marketplace. His search for the perfect wall on which to paint, and the subject matter he ultimately winds up painting on one of the walls found in his search, is priceless. The Joyce Cary novel, and its companions in the Jimson trilogy (`Herself Surprised' and `To Be a Pilgrim') are well worth reading, but this movie is a very British, very engaging classic. In many ways, it's the movie that `Pollack' (good though it was) should have been.