Kratos and dunamis appear as “power” in Plato’s dialogs but they signify differently. Kratos is a practice of mastery, according to which “might makes right.” Dunamis is the individual and collective capacity to do or not to do, a capacity that makes exercises of power of any kind possible. This lecture explores in Gorgias and other dialogs the ethical and political implications of the dialogs’ representations of kratos in terms of dunamis, including for democracy as demokratia.