Motivational Internalism is the thesis that, necessarily, moral beliefs are accompanied by motivational states. While another's testimony might transmit knowledge and justification, it cannot warrant motivational states such as moral emotions. Thus, Internalism provides a compelling explanation of “Pessimism,” the view that there is something illicit about forming moral beliefs by testimony. This paper presents a nonconstitutive reading of the Internalist thesis and then argues that it supports Pessimism in the form of a defeasible presumption against moral deference. It also argues against views which explain Pessimism by appeal to requirements on moral belief formation.