Have you ever really tried to answer that question?Art is many things to many people. Good art for me means I like it, I could sit with it for a long time, it reminds me of something that mattered. That's all very subjective. I am not trying to even go to objective art or integral art.
Art is, in one way or another, the product of creativity. Art is considered art in the eye of the beholder. I suppose that implies a sentient observer. Art involves the aestetic, not functionality. Art also can be the practice of a skill in a masterful way, as in the art of medicine rather than the mere practice of medicine. When I feel into what that difference means for me, it includes the state of the practitioner, not only is there knowledge and experience and a certain way of delivery or action, there is a certain space, a flow, and a vibration of compassion that gets transmitted in the transaction. When I look at art, it has an effect on me and I can determine if it helps me or transports me into a higher vibrational space or not. Art can depict that which is hidden to the normal view, and so can be illuminating or shocking. Myself, I have seen and experienced shocking enough for the time being, I am looking for something else. Beauty, a higher space, transformational effects...things like that.
Art can be used as a practice, a spiritual practice. Here I am thinking of drawing as taught in the series: "Draw good now", or "Zen Flute".