Final answer:
F. Scott Fitzgerald presents the 1920s as an era of grand illusion and dissipation in 'The Crack-Up,' an interpretation reflected in the profligate lifestyles of his characters, notably Jay Gatsby in 'The Great Gatsby,' which parallels the excess and despair of that time.
Step-by-step explanation:
In his personal essay 'The Crack-Up', F. Scott Fitzgerald describes his life during the 1920s as both grand and disillusioning. He reflects on the era with a sense of regret for the profligate lifestyle he led with his wife Zelda, which eventually drained their finances.
This period, for Fitzgerald, was characterized by the illusion of problem-free living and the dream of effortless success, as they basked in the short-lived glory of his early literary achievements. However, the underlying reality of the 1920s, marked by excess and eventual despair, is mirrored in Fitzgerald's life and vividly depicted in his works, most notably in The Great Gatsby.
Here, he portrays the character Jay Gatsby as living a lavish and unscrupulous life, in love with another man's wife, a direct reflection of the era's moral ambiguities and the eventual doom that follows a life of superficial excess.