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.
Daniel Kahneman
It is difficult to determine precisely when Kahneman's research began to focus on hedonics, although it likely stemmed from his work on the economic notion of utility. After publishing multiple articles and chapters in all but one of the years spanning the period 1979–1986 (for a total of 23 published works in 8 years), Kahneman published exactly one chapter during the years 1987–1989. After this hiatus, articles on utility and the psychology of utility began to appear (e.g., Kahneman & Snell, 1990; Kahneman & Thaler, 1991; Kahneman & Varey, 1991). In 1992, Varey and Kahneman introduced the method of evaluating moments and episodes as a way to capture "experiences extended across time". While Kahneman continued to study decision-making (e.g., Kahneman, 1992, 1994; Kahneman & Lovallo, 1993), hedonic psychology was the focus of an increasing number of publications (e.g., Fredrickson & Kahneman, 1993; Kahneman, Fredrickson, Schreiber & Redelemeier, 1993; Kahneman, Wakker & Sarin, 1997; Redelmeier & Kahneman, 1996), culminating in a volume co-edited with Ed Diener and Norbert Schwarz, scholars of affect and well-being.