Kenneth P. Fishkin proposes a taxonomy for analyzing tangible user interfaces (TUIs) using the axes of embodiment and metaphor. For embodiment, he identifies a scale from full to distant to describe how closely the output is tied to input. For metaphor, he examines whether the system effect matches real-world actions (verb metaphor) or objects (noun metaphor). Examples like I/O Brush and metaDESK demonstrate nearby embodiment, while TooTown shows environmental embodiment. The taxonomy allows comparison of TUI designs and understanding of the design space.