One day at the hospital (Tomas is a surgeon), Tereza calls and tells him she is coming to Prague on business. He is ecstatic, and she arrives the next day with a book—a copy of Anna Karenina—under her arm. Tomas asks where she is staying, and Tereza says she doesn’t have a hotel yet. She left her suitcase at the train station, she says, so Tomas immediately takes her to get it, bringing both Tereza and her enormous suitcase back to his flat.
Tereza’s massive suitcase is symbolic of her “heavy” character. She is the complete opposite of Tomas (he’s a womanizer who avoids love), and she values committed relationships and monogamy. When Tomas brings Tereza and her suitcase back to his flat, he is inviting both Tereza and her heaviness into his life, a move that is at odds with his lightness.
Inviting Tereza to stay at his flat violates Tomas’s way of living. Tomas, who has long since divorced his wife and abandoned his son, Simon, is a bachelor, and he is unable to sleep next to a woman. He has plenty of mistresses, but he always asks them to leave by midnight. Sleeping next to Tereza, however, he wakes holding her hand and looks at the massive suitcase sitting by the bed. He thinks again that she is a child floated downstream to him in a basket, but then stops himself. Metaphors are dangerous, Tomas thinks, and can quickly lead to love.
Later, after Tomas has fallen in love with Tereza, the narrator again claims that metaphors lead to love, as Tereza has made her way into Tomas’s “poetic memory.” Tomas denies that sex and love are related and instead argues that love is the desire to sleep next to someone else. Here, it is clear that Tomas is falling in love with Tereza, and this is reflected in his glance toward her “heavy” suitcase. Tereza is the embodiment of love, an undeniably heavy emotion. Despite this love, Tomas still sees himself in a position of power over Tereza, as he again refers to her as a helpless infant in a basket. Tomas’s constant need to place Tereza in an inferior position implies that, in love, one person will always be in a position of power over the other.