This article invalidates a central objection that has been brought up against Spinoza’s idea of idea doctrine as a theory of consciousness. Key point in the argument is that the perfection of ideas of ideas is as variable as the perfection of ideas and corresponds to the perfection of the associated bodies. This allows ideas of ideas to account for various degrees of consciousness. In its application to human beings the theory covers important aspects of consciousness: to know that one knows a thing, to know what one knows and to know that is our mind that knows the thing. The doctrine is a theory of the self-reflectivity of ideas that explains the immediate awareness of thoughts. The author argues that the idea of idea doctrine is the make-up of a comprehensive theory of consciousness throughout nature.
Keywords: Spinoza, ideas of ideas, consciousness