LitCharts assigns a color and icon to each theme in The Unbearable Lightness of Being, which you can use to track the themes throughout the work.
Time, Happiness, and Eternal Return
Lightness, Weight, and Dichotomies
Sex, Love, and Duality of Body and Soul
Words and Language
Power, Politics, and Inequality
Summary
Analysis
Later that night, Tomas develops terrible stomach pains, a condition he always experiences with deep depression. He usually keeps medicine on hand, but he has not stocked the cabinet recently. Tereza comments on how terrible Prague has been lately and suggests moving to the country. They won’t run into the editor there, or colleagues from the hospital. Nature hasn’t changed, Tereza says, and Tomas agrees that perhaps she is right. He would probably be bored, however, Tereza says to Tomas, if he had to be alone with her in the country.
Without Prague’s never-ending supply of women, it would be difficult for Tomas to continue his womanizing, and Tereza’s passive-aggressive comment draws attention to this and implies that she alone will not be enough for him. Meanwhile, Tomas’s stomachache is evidence of his depression and unhappiness. He resents both Tereza and what his life has become, but he has little to look forward to, especially in the country.
Active
Themes
Tomas’s stomach aches even more. He thinks that his womanizing may be “something of an ‘Es muss sein!’—an imperative enslaving him.” He needs a vacation from all enslavements. Just like his vacation from the operating table, he needs a vacation away from the women he cuts open with his metaphorical scalpel.
By referring to his womanizing as an “Es muss sein!” Tomas implies that he has no control over it. Not only does this make him appear powerless, it also implies that his womanizing, which is supposed to be light, is actually heavy and weighing him down.