In Paul Auster's novel "4 3 2 1," the character reflects on the inevitability of challenges and difficulties in life with the quote, "The only constant in this world is shit, boy." This statement encapsulates the idea that hardship and adversity are universal experiences that everyone encounters. It serves as a poignant reminder that no matter the circumstances, one must prepare for and deal with struggles as a part of life.

Auster's work often explores themes of fate and identity, and this quote emphasizes a gritty, realistic perspective on existence. The acknowledgment that unpleasantness is a constant suggests that individuals must learn to navigate through both the beautiful and the harsh aspects of their journeys. Ultimately, it invites readers to reflect on resilience in the face of constant change and difficulty.