In this chapter we examine Brentano's system and begin to give an overview of what can be said to still be of value within it. We will also explore what aspects of the system of the PES must be rejected in order to preserve those of its core insights that may be usefully applied to problems in contemporary philosophy of mind. We start with an overview and selected criticism of some of the leading paradigms in recent philosophy of mind. After this, an outline and explanation of the metaphysical dualism and the anti-materialist context of Brentano's onelevel theory of consciousness is given. With Brentano's philosophical strategy for separating the psychic from the physical further explained, we then begin to present an overview of the basic framework of the 1874 system in the PES before turning to criticism.