This is a really good introduction to dual-process psychology and contains chapters on how the adaptive unconscious (often called System 1 in other works) affects our control of our behaviour, our knowledge of ourselves, our knowledge of our motives and introspection. Wilson's writing is clear, and his recounting of the empirical evidence is useful.
The beginning of the book starts with a brief analysis of how Freud's notion of the unconscious compares with that of the adaptive unconscious. This comparison touches too on Descartes' view of the mind. All of this is useful, but it is brief. A more developed comparison would've been interesting to see. Nevertheless, the book is readable without it, and contains detailed descriptions of many of the features and attributes belonging to the adaptive unconscious.