  The causal-stable Muller-Israel-Stewart (MIS) theory is known to have a
finite number of out of equilibrium derivative order corrections but requires
treating the viscosity tensor as a separate degree of freedom with its own
equations of motion, apart from the fundamental fluid degrees of freedom like
velocity and temperature. In this work, I will show that it is possible to
rewrite the MIS theory only in terms of velocity and temperature, but the
resultant constitutive relation for dissipation must include all orders of
gradient corrections. In this work I will argue that an all-order resummation
of gradient contributions is equivalent to introducing new `non-fluid' degrees
of freedom in the MIS theory. It will also be shown, using the relativistic
quantum causality condition, that any finitely truncated order of derivative
correction, however high it is, leads to a theory that is acausal, unless the
corrections are infinitely summed up to all orders.
