Watch it in action, here.
After years (decades?) of walking around that stone, the chair (which is about an inch tall) has walked itself into a literal rut.
I absolutely love his work, but it's hard to capture in a photograph because his gestural sculptures each perform very small, slow, natural, subtle movements
... and it's the movement itself that is the biggest feature (and beauty) of his art.
However, this worn stage for this bright yellow chair encapsulates years of movement in a single moment.