This 'Weeping Willow' painting was made with oil on canvas by Claude Monet, though the exact date is unknown, but it resides now in the Musée Marmottan Monet in Paris. Here, we can see how brushstrokes function as the building blocks of vision. There’s a real push and pull between near and far, absence and presence. The material aspect of this painting is so important, you can see the thickness of the paint in the layering of strokes around the upper left of the frame, where a flurry of turquoise and white seem to dance amongst the foliage. This layering hints at the unseen, the multitude of marks that lie beneath the surface. It is a bit like the palimpsest of a painting, an echo of the layers of history beneath the top coat. Monet’s late work, including this painting, anticipated the all-over compositions of artists like Joan Mitchell, and they both invite a kind of looking that prizes ambiguity.