In "Darkness Visible: A Memoir of Madness," William Styron reflects on his experience with depression, suggesting that it was not an unexpected arrival in his life. He likens the condition to a persistent presence, having knocked on his door for many years before fully manifesting. This metaphor illustrates how depression can be a long-standing struggle, often lurking just beneath the surface.

Styron's insights emphasize the idea that mental illness can gradually build up over time, often without clear recognition until it overwhelms an individual. His narrative invites readers to consider the subtleties of depression and how it may resemble an unwelcome but familiar entity, highlighting the complexities of understanding and confronting such a profound emotional challenge.