  We show how to derive a consistent quantum theory of radiation reaction of a
non-relativistic point-dipole quantum oscillator by including the dynamical
fluctuations of the position of the dipole. The proposed non-linear theory
displays neither runaway solutions nor acausal behaviour without requiring
additional assumptions. Furthermore, we show that quantum (zero-point)
fluctuations of the electromagnetic field are necessary to fulfil the second
law of thermodynamics.
