The whole natural world depends on the diffusion of water with stuff suspended in it, and every living thing uses capillary action. Watercolor painting, therefore, is the art medium that is truest to nature. By grinding naturally-occuring colors to powder, lifting and placing them approximately where you want them on the natural substrate we call paper, and allowing capillary action to take effect and move and mix them, we embrace nature rather than fight it. The intelligence of the artist becomes a conduit for expression, not exactly the physical source, not an exactly-engineered result, but a work of art that, like life, has an inexorable process of its own. Art sits lightly upon the watercolor artist, who must work very lightly in response. The colors and the paper and the brush and the water are already in their own state of process and equilibrium. All that’s left, the remaining variable, is you. Watercolor is the most challenging medium of all, because it requires you to master yourself.