  To induce transport, detailed balance must be broken. A common mechanism is
to bias the dynamics with a thermodynamic fuel, such as chemical energy. An
intriguing, alternative strategy is for a Maxwell demon to effect the bias
using feedback. We demonstrate that these two different mechanisms lead to
distinct thermodynamics by contrasting a chemical motor and information motor
with identical dynamics. To clarify this difference, we study both models
within one unified framework, highlighting the role of the interaction between
the demon and the motor. This analysis elucidates the manner in which
information is incorporated into a physical system.
