The Boundary of the Sayable

Engraved interactive hyperbolic plane

Drag the plate, or focus it and use the arrow keys, to travel across the hyperbolic plane toward the boundary. Tab to the caption term to read its definition in the lectern; Escape clears it.

Fig. VI — the hyperbolic plane: every step toward the boundary halves; the rim is at infinite distance. The Universality of Unsayability.

Design note: the disk is drawn because the form says the concept — in hyperbolic geometry the boundary circle is infinitely far from every interior point, so discourse may travel forever toward the boundary it intuits without ever reaching it. The rim itself is never drawn: what a reader sees there is light, not line — the tiling turns to silhouette against it, and no stroke ever reaches it.