The assertion that the calculated binding free energies ∆Gcal or binding free energy differences ∆∆Gcal follow a normal distribution conflicts with our observation that such data are not in general normally distributed . Newtonian molecular dynamics is inherently nonlinear, and this is the underlying reason why the dynamics is chaotic in the technical sense. Not only are individual trajectories extremely sensitive to initial conditions, they become increasingly inaccurate as the duration of such a simulation unfolds. They manifest long range correlations which are not present in Gaussian statistics.