In "The Marriage Plot" by Jeffrey Eugenides, the protagonist, Leonard, grapples with his struggle against mental illness. Despite his disdain for lithium, the medication acts as a protective barrier against overwhelming sadness. He recognizes the lurking emotions but feels shielded from their full impact, allowing him to experience their essence without being consumed by them.

This metaphor of squeezing a baggie filled with water effectively illustrates Leonard's complex relationship with his emotions and medication. While he can sense the depth of his feelings, lithium helps him maintain some control, preventing him from becoming overwhelmed by despair.