The quote suggests that pain tends to be the only lasting memory we retain, as it leaves a mark that persists over time. Unlike pleasure, which often fades once experienced, pain remains vividly etched in our minds. This highlights the enduring nature of painful experiences compared to the fleeting nature of happiness.

Moreover, the statement implies that pleasure is self-contained and doesn't linger as a memory, whereas pain creates a deeper, more permanent imprint. It underscores the idea that suffering has a more profound impact on our psychological memory, making it a more persistent part of our life experiences.