Ambiguity in the analysis of "autonomous" switches and motors. It was necessary to demonstrate the operation of catenane 6 indirectly as described because there is no single observable that can be used to quantify the directed motion of a freely rotating motor. The same approach has been taken to demonstrate the behavior of all information ratchet-based rotary motors reported to date. 23 Indeed, compared with the operation of such networks in catalysis where there is a clear observable (e.g., product ee), the autonomous operation of molecular motors can be opaque, even when the chemistry involved is relatively simple.