The Concept of Anxiety
All of Kierkegaard's books have either a preface, dedication, or prayer at the beginning. This book includes a lengthy introduction. "The Concept of Anxiety" was published on exactly the same date as "Prefaces", June 17, 1844. Both books deal with Hegel’s idea of mediation. Mediation is a common thread throughout Kierkegaard’s works. His work up to this point was to show that faith was being mediated by knowledge. Here he takes up the questions of sin and guilt.
The Mask of Sanity
The first edition was published in 1941, with the subtitle then being 'An attempt to re-interpret' rather than as later 'to clarify'. Cleckley says in the preface that the book "grew out of an old conviction which increased during several years while I sat at staff meetings in a large neuropsychiatric hospital". He added that after commencing full-time teaching duties he found similar patients to be as prevalent in a general hospital, outpatient clinic and the community. In later editions he explains that the basic concepts presented in 1941 were based primarily on "adult male psychopaths hospitalized in a closed institution" for several years. Cleckley had worked for a number of years at a United States Veterans (military) Administration hospital, before taking up full-time teaching responsibilities at the University of Georgia School of Medicine.