Milan Kundera's quote emphasizes the importance of acknowledging change in our understanding of life. He argues that we cannot fully grasp human existence if we ignore the fluid nature of reality. Those aspects of our lives that once were significant cannot simply be revisited or reconstructed as they were, as time alters our perceptions and experiences. This highlights the ephemeral quality of life and the inevitability of change.

By stating that "a reality no longer is what it was when it was," Kundera invites us to reflect on how our past influences our present but cannot be duplicated. This perspective encourages us to embrace the present and recognize that every moment is unique, shaped by both our memories and the passage of time. To understand life, we must accept this dynamic nature rather than cling to an idealized past.