Letter from Thomas Gold to Professor Peter A Sturrock, Department of Space Science and Astrophysics, Institute for Plasma Research, Stanford University, Via Crespi, Stanford, California Re-states his remark that "In order for a theory to be useful, it must be possible for it to be proven wrong". Sturrock is welcome to quote him and there is probably a similar statement in the Bondi and Gold Steady State paper. 2 July 1969