In the scholium to proposition 49 of Part 2 of the Ethics, Spinoza addresses a number of prejudices that tend to obscure the essentially judgmental nature of ideas. One warning is issued against those who do not distinguish accurately between ideas and images, and, for this exact reason, fail to see that every idea, insofar as it is an idea, always involves an affirmation that something is the case. This paper shows that in order to properly understand Spinoza's remarks in this passage, we must redirect attention to Descartes’ Meditations on First Philosophy, and more particularly to the objections raised against them by Hobbes. Specifically, I argue for the identification of Hobbes and other likeminded “imagists” as Spinoza's main targets, and not, as is often assumed, Descartes himself or Cartesians in general. My identification not only resolves interpretative confusion surrounding this passage, but it also confirms Spinoza's commitment to a key rationalist assumption: the existence of a mind that can grasp or exhibit natures by clear and distinct perceptions. While both adequate and inadequate ideas are necessitated beliefs or judgments in which we assent to something, virtue consists in being propelled by the intellect.