This review, provided by April Koester, focuses on the Third Foundation of the Four Foundations of Mindfulness, which is intended to describe how the characteristics of various states of consciousness can affect our self-experiences.  The mind operates like a filter, “coloring” perceptions through various states such as desire, aversion, dullness, agitation, etc.  The goal of mindfulness and internal investigation is to understand the conditioning of the filtering process and, through Right Effort, create qualities of consciousness that provide an unfiltered view of the impermanent and non-self characteristics of subjective experience.