  Boltzmann's constant reflects a historical misunderstanding of the concept of
entropy, whose informational nature is obfuscated when expressed in J/K. We
suggest that the development of temperature and energy, historically prior to
that of entropy, does not amount to their logical priority: Temperature should
be defined in terms of entropy, not vice versa. Following the precepts of
information theory, entropy is measured in bits, and coincides with information
capacity at thermodynamic equilibrium. Consequently, not only is the
temperature of an equilibrated system expressed in J/bit, but it acquires an
operational meaning: It is the cost in energy to increase its information
capacity by 1 bit. Our proposal also supports the notion of available capacity,
analogous to free energy. Finally, it simplifies Landauer's cost and clarifies
that it is a cost of displacement, not of erasure.
